LIBRARY 
 CALIFORNIA 
 
 MEMCAL 
 
 LUEMAUOf 
 
 GIFT or 
 
 COLLEGE OF PHARMACY 
 
 DEPARTMENT 
 
lacy 
 
TEXT-BOOK 
 
 OF 
 
 ORGANIC CHEMISTRY. 
 
 LEFFMANN AND LAWALL. 
 
BY THE SAME AUTHOR. 
 
 SELECT METHODS IN FOOD ANALYSIS. 
 
 By HENRY LEFFMANN and WILLIAM BEAM. 
 Second Edition, Revised. 8vo. Illustrated. Cloth, net, $2.50. 
 
 EXAMINATION OF WATER 
 
 For Sanitary and Technical Purposes. 
 Fifth Edition, Revised. i2mo. 140 Pages. Cloth, net, $1.25. 
 
 ANALYSIS OF MILK AND MILK PRODUCTS. 
 Third Edition, Revised. 12010. Illustrated. Cloth, net, $1.25. 
 
 HANDBOOK OF STRUCTURAL FORMULA. 
 
 Containing 180 Structural and Stereo-chemic Formulae. 
 i2mo. Interleaved. Cloth, net, $i.co. 
 
 A COMPEND OF CHEMISTRY. 
 
 Inorganic and Organic, including Urinary Analysis. 
 
 Especially Adapted to Students in Medicine and Dentistry. 
 
 Fourth Edition, Revised. i2mo. Cloth, net, ST.OO. 
 
 Interleaved for taking notes, $1.25. 
 
 SANITARY RELATIONS OF THE COAL-TAR COLORS. 
 
 By THEODORE WEYL. 
 
 Authorized Translation by DR. LEFFMANN. 
 
 i 2 mo. * 154 Pages. Cloth, net, $1.25. 
 
TEXT-BOOK 
 
 ORGANIC CHEMISTRY 
 
 HENRY LEFFMANN, A.M., M.D. 
 
 Professor of Chemistry at the Wagner Free Institute of Science of Philadelphia and at 
 The Woman's Medical College of Pennsylvania 
 
 CHARLES H. LAWALL, PH.G. 
 
 Instructor in Pharmacy and Pharmaceutical Arithmetic at the Philadelphia College of 
 Pharmacy ; Chemist to the Dairy and Food Commissioner of Pennsylvania 
 
 California CoIEogo of-Pharmacy 
 
 WITH ILLUSTRATIONS AND EXPERIMENTS 
 
 PHILADELPHIA 
 
 P. BLAKISTON'S SON & CO. 
 
 1012 WALNUT STREET 
 1905 
 
COPYRIGHT, 1904, BY P. BLAKISTON'S SON & Co. 
 
 PP.ESS or WM. r. FELL COMPANY 
 
PREFACE. 
 
 This book is offered as an aid to the study of organic 
 chemistry in connection with general and professional col- 
 lege courses.- The difficulty in the preparation of such a 
 work is to determine what to exclude. We have endeav- 
 ored to give consideration to the more important features 
 of the science, especially in its applications. Polarisa- 
 tion of light has been treated in some detail on account of 
 the importance of it in the study of molecular structure. 
 
 Some descriptive topics that are often passed over very 
 briefly have been given considerable space. Among these 
 are to be noted the sections on Enzyms, Purins, Alkaloids 
 and Proteids. 
 
 The experiments have been selected with a view of 
 illustrating all the important types of organic compounds 
 and reactions, and at the same time avoiding danger to 
 the student and tediousness and complexity of manipu- 
 lation. 
 
 All temperatures are centigrade. 
 
 119 SOUTH FOURTH ST., PHILADELPHIA, 
 
 October, 1904. C. H. L. 
 
 42; 
 
CONTENTS. 
 
 PAGES 
 
 PRINCIPLES . . . 9-48 
 
 Proximate and Ultimate Composition Physico- 
 chemical Data Derivatives and Synthetic Com- 
 pounds Transformations Structure and Classi- 
 fication Percentage Composition and Formulas 
 Optical Activity Isomerism Organic Radi- 
 cles Homologous Series General Formulas 
 Nomenclature . 
 DESCRIPTIVE CHEMISTRY 49-215 
 
 ALIPHATIC COMPOUNDS. 
 
 Hydrocarbons Paraffins and Derivatives Alco- 
 hols Ethers, Esters Aldehydes Ketones 
 Fatty-acids Olefins and Derivatives Meth- 
 enyl and Derivative Fats Allyl and Deriva- 
 tives Carbohydrates Glucosides . 
 
 CYCLIC COMPOUNDS. 
 
 Homocyclic Compounds: Benzene and Deriva- 
 tives Naphthalene and Derivatives Anthra- 
 cene Coal-tar Colors. 
 
 Ter penes: Camphors Essential Oils Resins. 
 Heterocyclic Compounds: Pyridin and Derivatives 
 Quinolin . 
 
 CYANOGEN AND DERIVATIVES: Cyanides Cyanates 
 Thiocyanates Fulminates Hydrazoates. 
 
 AMMONIUM DERIVATIVES: Amines Amides Urea 
 Amido Acids. 
 
 Azo- HYDRAZO- AND DIAZO-COMPOUNDS: Diazoben- 
 zene Phenylhydrazin Diazo- reaction . 
 
 ALKALOIDS. 
 
 Ptomaines Leucomaines Purins . 
 
 PROTEIDS OR ALBUMINOIDS: Lecithins. 
 
 ENZYMS. 
 
 INDEX. 
 
ORGANIC CHEMISTRY. 
 
 PRINCIPLES. 
 
 ORGANIC CHEMISTRY is primarily the chemistry of sub- 
 stances produced by living tissues. These are very numer- 
 ous, and other bodies can be obtained from them, which 
 are analogous to the primary organic bodies, and are in- 
 cluded in the same groups. Transformations and modi- 
 fications may be carried so far as to produce substances 
 which are clearly inorganic, consequently it is not pos- 
 sible to establish a distinct boundary between inorganic 
 and organic chemistry. It was formerly supposed that 
 organic bodies are distinct in that the original compounds 
 could only be produced by vital action, but, in 1828, 
 Wohler succeeded in producing urea by heating ammonium 
 cyanate, and thus set aside the supposed distinction. 
 Since that time many similar results have been obtained, 
 and it is now generally believed that the chemical affinities 
 concerned in the formation of compounds by living tissues 
 are the same as those operating in inorganic bodies. It 
 must, however, not be supposed that the chemistry of vital 
 action has been solved, or even brought into entire analogy 
 with inorganic chemistry. Many points yet remain to 
 be explained. 
 
 A characteristic of the products of vital action is that 
 they all contain carbon, hence it has been proposed to sub- 
 
 9 
 
10 ORGANIC CHEMISTRY. 
 
 stitute for organic chemistry the title "Chemistry of the 
 Carbon Compounds." No special advantage is gained 
 by this. Moreover, several compounds containing silicon 
 in combinations analogous to natural organic bodies have 
 been obtained, so that the later title is equally insufficient. 
 
 Carbon, hydrogen, oxygen and nitrogen are most 
 abundant in organic compounds; sulphur and phosphorus 
 are present in the complex forms that are found in tissues 
 of higher function. Iron is found in several, among which 
 are the coloring matters of blood and green vegetable 
 tissue. Copper is also noted in a few cases. By lab- 
 oratory methods many substances have been obtained 
 into which other elements, e. g., chlorine, bromine, iodine, 
 mercury and arsenic, have been introduced. These are 
 often analogous in many ways to natural organic bodies, 
 but not equivalent to them in biologic function. 
 
 The following list of bodies from natural sources will 
 illustrate the degrees of complexity exhibited by organic 
 compounds : 
 
 C 10 H 16 ............. Terpene. 
 
 C a H 22 O n ........... Cane sugar. 
 
 C 10 H 14 N 2 ........... Nicotine (from tobacco). 
 
 C 17 H 19 NO 3 .......... Morphine (from opium). 
 
 C 2 H 7 NSO 3 .......... Taurin (from bile). 
 
 C 3 H 9 PO 6 ........... Glycerophosphoric acid (from brain tissue) . 
 
 B ....... Hematin (from blood corpuscles). 
 
 Proximate and Ultimate Composition. The tissues of 
 plants and animals, or the immediate products of their 
 transformations, are generally mixtures of several inde- 
 pendent substances. Butter is a mixture of four or five 
 fats common rosin contains two or sometimes three 
 distinct bodies; opium and Peruvian bark are still more 
 complicated, and brain and muscle structures are so com- 
 
PRINCIPLES. II 
 
 plex that as yet complete analyses have not been made 
 of them. The substances which thus exist naturally in a 
 state of mixture are called proximate principles; the 
 separation and identification of them is called proximate 
 analysis, and such of them as give characteristic qualities to 
 the articles in which they occur are often called active 
 or essential principles; atropine, for instance, is the active 
 principle of belladonna, for although many different bodies 
 are contained in belladonna, atropine is the one upon which 
 its physiological activity mainly depends. The ultimate 
 constituents of any substance are the elements, e. g., carbon 
 and hydrogen, that it contains; the detection of these 
 elements and determination of their amount is ultimate 
 analysis. This is simple in principle but in practical 
 operation involves much care and skill. The following 
 is an outline of the more important procedures: 
 
 Carbon and hydrogen are determined by burning a 
 weighed portion of the substance in a current of oxygen 
 or in contact with some oxidising agent. The carbon is 
 converted into carbon dioxide, the hydrogen into water. 
 These are absorbed by suitable materials in separate 
 vessels and the increase in weight of these will permit of 
 calculation of the carbon and hydrogen in the substance. 
 If oxygen is the only other element present it is deter- 
 mined by difference. Nitrogen is determined either by 
 measuring it free, or by conversion into amine (ammonia), 
 NH 3 . A method now much used is to heat the sub- 
 stance with strong sulphuric acid with or without special 
 oxidising agents, by which the nitrogen is converted into 
 ammonium sulphate. This is termed the Kjeldahl method. 
 Chlorine, iodine, and other unusual elements require special 
 methods that need not be described here. Sulphur is usu- 
 ally converted into sulphate by oxidation. 
 
12 ORGANIC CHEMISTRY. 
 
 Nitrogen may be detected in many substances by con- 
 version into cyanide. For experimental illustration of 
 this, see under "Cyanogen." 
 
 Physico-chemical data (constants) are of value in iden- 
 tifying organic bodies, ascertaining purity and elucidating 
 formulas. The following are the more widely applicable 
 methods : 
 
 Specific Gravity. Specific gravities of liquids and solids 
 are generally expressed by comparison with water. Con- 
 fusion and inconvenience have arisen from the fact that 
 results have been referred to water at different temperatures 
 as unity. The temperatures of observation and com- 
 parison should always be expressed. ~~ indicates a 
 determination at^ 100 and comparison with water at 15.5 
 as unity. It is best to compare the substance and the 
 standard at the same temperature. 
 
 Pyknometer or Specific -gravity Bottle. This is a generally 
 applicable means of determining specific gravity, and is 
 capable of furnishing good results. It is a bottle with a 
 perforated stopper adjusted to hold a certain weight of 
 water at a standard temperature, usually 15.5. Bottles as 
 sold are often inaccurate. The weight of water that a 
 bottle holds should be carefully determined. 
 
 Sprengel Tube. This is a form of pyknometer with 
 which a high degree of accuracy is attainable; it is es- 
 pecially suitable for determinations at the boiling-point of 
 water. It consists essentially of a thin glass U-tube ter- 
 minating in two capillary ends bent at right angles and each 
 provided with a ground cap. One of these capillary tubes 
 must have a smaller caliber than the other not larger than 
 0.25 mm. The larger tube should bear a mark at m. The 
 tube is filled by immersing b in the liquid under examina- 
 tion, connecting the smaller end with a large glass bulb, 
 
PRINCIPLES. 13 
 
 and applying suction to the latter by means of a rubber 
 tube. If now the rubber tube be closed, the glass tube 
 will fill automatically. It is placed in water, the ends 
 being allowed to project, and the water is brought to 
 the proper temperature. A conical flask may be used 
 to contain the water, the ends of the Sprengel tube 
 being supported by the neck. The mouth of the flask 
 
 FIG. i. 
 
 FIG. 2. 
 
 should be loosely covered. As the liquid expands it 
 will drop from the larger orifice. When this ceases, the 
 liquid is adjusted to the mark at m. If beyond the point, 
 a little may be extracted by means of a roll of paper. The 
 tube is then taken out of the bath, the caps adjusted, 
 the whole thoroughly dried, allowed to cool, and weighed. 
 The same operation having been performed with dis- 
 
I 4 ORGANIC CHEMISTRY. 
 
 tilled water, the calculation of the specific gravity is made 
 as usual. 
 
 Westphal Balance. This affords a convenient means of 
 determining specific gravity. It consists of a delicate steel- 
 yard provided with a counterpoised plummet. The latter, 
 being immersed in the liquid, the equilibrium is restored by 
 means of weights or riders, the value of which is directly 
 expressed in figures for the specific gravity without calcula- 
 
 FIG. 3. 
 
 tion. Thus, the rider A 1 is of such a weight as to express 
 the first decimal place, and will be represented by any of 
 the figures from o to 9 according to its position on the beam. 
 Similarly the riders A , B and C furnish the figures for the 
 second, third and fourth decimal places respectively. The 
 weight A 2 is used in the case of liquids heavier than water. 
 The ordinary form of Westphal balance is untrust- 
 worthy, but good instruments are made by some European 
 manufacturers. 
 
PRINCIPLES. 15 
 
 The principle of the hydrostatic balance may be applied 
 by using a plummet (that sold with the Westphal balance 
 will serve) with the ordinary analytic balance. Testtubes 
 weighted with mercury and sealed in the flame may also be 
 used. The plummet is suspended to the hook of the bal- 
 ance by means of a fine platinum wire. The specific 
 gravity of any liquid may be determined by noting the loss 
 of weight of the plummet when immersed in the liquid and 
 dividing this by the loss in pure water. 
 
 Hydrometers are much used for the determination of the 
 specific gravity of liquids, but the indications are less 
 reliable than by the foregoing methods . Sensitive hydrom- 
 eters with slender stems, and accurately graduated, are 
 now obtainable. These are capable of furnishing good 
 results. Care should be taken to make the reading at the 
 top, center or bottom of the meniscus according to the 
 method used in the graduation of the instrument. In- 
 struments intended for use with opaque liquids should be 
 graduated to be read at the top of the meniscus. 
 
 The actual specific gravity of any substance is the ratio 
 of its density at a given temperature to that of water at the 
 same temperature. Statements made upon any other basis 
 than this may be converted into actual specific gravity 
 by calculation from the table of density of water. Thus, 
 a determination of specific gravity of 0.8000 at ^ may 
 be converted into actual specific gravity (5) as follows : 
 
 Density of water at 15 = 0.99916 
 100 = 0.95866 
 i 00 i 00 
 
 15" Too 5 
 
 Therefore, 95866 : 0.99916 : : 0.8000 : 0.8337 (actual specific gravity 
 at 100). 
 
 Melting and Solidifying Points. The determination of 
 
ORGANIC CHEMISTRY. 
 
 these is often difficult. Many substances, especially fats, 
 assume conditions exhibiting abnormal melting-points, 
 and also frequently solidify at a temperature very different 
 from that at which they melt. If, in the preparation of 
 any substance for determining its melting-point, it is 
 necessary to make a previous fusion, the mass should be 
 allowed to rest not less than twenty-four hours after 
 
 solidification before making 
 the experiment. Chemists 
 disagree as to whether the 
 melting-point should be con- 
 sidered to be that at which 
 the substance begins to be 
 liquid or that at which the 
 liquid is perfectly clear Ordi- 
 nary thermometers are fre- 
 quently inaccurate, the error 
 amounting to a degree or more. 
 No observations in which pre- 
 cision is required should be 
 made with unverified instru- 
 ments. 
 
 The following method for 
 determining melting-points is 
 suitable for many technical 
 
 purposes. By substituting strong brine or glycerol for 
 the water in the bath observations may be made at tem- 
 peratures beyond the limits of o and 100. 
 
 The substance is heated to a temperature slightly above 
 its fusing-point, drawn into a very narrow glass tube, and 
 allowed to solidify for not less than twenty-four hours. The 
 tube, open at both ends, is attached by a wire or rubber ring 
 to a thermometer so that the part containing the substance 
 
 FIG. 4. 
 
PRINCIPLES. 
 
 is close to the bulb. The apparatus, immersed in water, is 
 heated at a rate not exceeding 0.5 per minute until fusion 
 takes place, when the temperature is noted. The tempera- 
 ture is allowed to fall and the point at which the sub- 
 stance becomes solid is also observed. To insure uniform 
 and gradual heating, it is necessary to immerse the vessel 
 containing the thermometer and tube in 
 another vessel filled with water (Fig. 4). 
 
 Boiling-point. For the determination of 
 boiling-point the apparatus shown in Fig. 5 
 is convenient. The thermometer is inclosed 
 in an outer tube, so that the portion of the 
 scale to which the mercury rises is im- 
 mersed in the vapor. If this is not done, 
 a correction must be applied for the error 
 produced by the cooling of the thermom- 
 eter tube. The bulb of the thermometer 
 does not reach into the liquid. A few frag- 
 ments of pumice-stone or broken clay 
 pipestems will prevent bumping. The 
 exit -tube at the lower end of the wide 
 tube connects with a condenser. The 
 barometric pressure must always be noted 
 and allowance made for the variation from 
 the standard pressure, 760 mm. 
 
 Vapor Density. This is the density of 
 the substance in a state of gas as compared with some 
 standard (generally hydrogen) at the same temperature 
 and pressure. The determination is largely used in organic 
 chemistry, and several methods of procedure have been 
 devised. The following, due to Victor Meyer, is the 
 simplest : 
 
 Fig. 6 shows the apparatus. A narrow glass tube BA 
 
 FIG. 5. 
 
ORGANIC CHEMISTRY. 
 
 is expanded at the closed end and arranged at the open end 
 to receive a caoutchouc stopper. C is a short delivery tube 
 which passes under the collecting tube in the pneumatic 
 trough. The outer cylinder F, containing the tube BA , is 
 
 filled with some liquid of 
 known boiling point higher 
 than that of the substance 
 to be tested. A portion of 
 the substance to be tested is 
 weighed into a small tube 
 and dropped into the inner 
 tube. It vaporises and drives 
 out an equal volume of air 
 which is collected in the tube 
 E. By this means the vol- 
 ume of vapor produced by 
 a given weight of the body 
 is determined, and by calcu- 
 lation with necessary correc- 
 tions the vapor density is 
 obtained. 
 
 Freezing Point of Solution, 
 Cryoscopy. This method , 
 originally applied for de- 
 termination of molecular 
 weights, is also used as a 
 clinical test, observations 
 being made especially with 
 urine and blood. The de- 
 pression of the freezing point of these is regarded as of con- 
 siderable value in diagnosis. In this clinical application 
 calculations of molecular weight are not made , the data being 
 interpreted by comparison with the average of normal fluids. 
 
 FIG. 6. 
 
PRINCIPLES. 
 
 An apparatus shown in Fig. 7 is used. The inner tube 
 .4, provided with a thermometer, 
 stirrer and a side tube, contains 
 the solution to be tested. It is 
 fastened by a cork in the wider 
 tube B and the whole is supported 
 in the vessel C (about 2500 c.c. 
 capacity) by means of a metallic 
 cover. In C is the freezing mix- 
 ture which can be stirred by 
 means of the rod shown. By 
 this arrangement the solution is 
 separated from the cooling mix- 
 ture by air and the cooling is 
 uniform and gradual. For accu- 
 rate determination the thermom- 
 eter should read at least to 0.02. 
 It is not necessary to observe 
 actual temperatures, but merely 
 the degree of depression as com- 
 pared with the freezing point of 
 the pure solvent. 
 
 Polarimetry. Polarimeters are 
 instruments used to measure the 
 extent and direction of the rota- 
 tion of the plane of polarised 
 light. They consist essentially 
 of a Nicol's prism as polariser, 
 a tube carrying the substance to 
 be tested, and a second Nicol's 
 prism or analyser, by which the 
 extent of rotation is measured. 
 In all forms some condition of the field of vision is fixed 
 
 FIG. 7. 
 
20 ORGANIC CHEMISTRY. 
 
 upon as the zero point, and the rotation of the analyser or 
 other manipulation necessary to restore this standard field 
 affords the measurement of the rotation caused by the inter- 
 posed substance. Several types of instrument have been 
 devised, of which two are most important. In one form, 
 devised by Soleil, white light is used and a colored field, 
 known as the transition tint, is taken as the zero point. In 
 the other type white light or monochromatic (yellow) light 
 is used and the zero point determined by equalising the 
 brightness of the field. Instruments of the first form are 
 unsatisfactory by reason of the difference in susceptibility 
 in the eyes of different persons to color-contrasts. The 
 instruments of the second type, commonly designated 
 shadow instruments (more correctly "penumbral") are 
 now more generally employed; they have been brought 
 of late years to a high degree of accuracy and conve- 
 nience. 
 
 In the Laurent apparatus, shown in Fig. 8, the mono- 
 chromatic light passes through the collimating lens A and is 
 polarised by the Nicol's prism B, which is so placed that it 
 may be moved, on its axis, over a small arc by means of the 
 lever C and clamped at any point ; by this the brightness 
 of the field may be varied and the sensitiveness of the in- 
 strument increased or diminished as may be needed. The 
 polarised beam then passes through a quartz plate of even 
 thickness, cut exactly parallel to the optic axis, and placed 
 so that it covers a semicircle of the field. At the other end 
 of the apparatus is the analysing prism E and the eye- 
 piece F fixed to a graduated disk. This combination can 
 be rotated upon its axis in a complete circle. Attached 
 arms carry view-lenses for reading the angle of rotation, 
 and. the instrument is set at zero by an independent ad- 
 justment by which the analysing prism is rotated without 
 
PRINCIPLES. 
 
 21 
 
 disturbing the position of the graduated disk. Ver- 
 niers are provided for close measurement. The monochro- 
 matic light must be obtained from a sodium flame, since 
 the thickness of the quartz plate is adjusted to these rays. 
 In use, the tube is filled with water, the instrument 
 directed to the source of light, and the adjusting milled head 
 turned until the disk is set at zero. The two portions of the 
 
 FIG. 8. 
 
 field should now appear equally illuminated. If this is not 
 the case, the position of the analyser must be altered by 
 means of the independent adjustment, the index remaining 
 undisturbed at the zero point. 
 
 The tube is filled with the liquid to be tested and again 
 placed in the instrument. If optically active, the plane of 
 the polarised light will be rotated and one-half of the field 
 
22 ORGANIC CHEMISTRY. 
 
 of observation will appear darker. The extent of rotation, 
 which will depend upon the nature of the substance and its 
 amount, is measured by rotating the analyser to the right or 
 left, as the case may be, until the halves of the field become 
 equally illuminated. 
 
 This form of instrument can be employed to measure 
 the rotatory power of all classes of substances, but other 
 forms give accurate indications only with substances 
 which have the same dispersive power as quartz, unless 
 monochromatic light be used. In the Schmidt and 
 Hansch penumbral instrument the division of the field is 
 obtained by a special construction of the polarising prism 
 and the restoration is accomplished by the adjustment of 
 compensating quartz-wedges constructed so as to produce 
 in the zero position no rotation. When an optically active 
 substance is interposed in the path of the ray, one of the 
 quartz-wedges must be moved to an extent sufficient to 
 overcome this rotation in order to restore the standard field. 
 The effect is dependent upon the fact that by this move- 
 ment the thickness of the quartz is increased or diminished 
 until it compensates for the rotation produced by the 
 solution. The extent of movement of the quartz is regis- 
 tered upon a linear scale, which is read by means of a lens 
 and vernier. White light is employed in making the 
 observations. A form of the Laurent instrument, with 
 quartz-wedge compensation, and employing white light, 
 is made. An instrument has been devised in which the 
 field is divided vertically into three zones, the central one 
 being a broad band. Duplicate Nicol prisms are so ar- 
 ranged that the lateral zones agree in tint, thus making 
 stronger contrast with the central zone. 
 
 Specific Rotatory Power. The specific rotatory power 
 of a substance is the amount of rotation, in angular degrees, 
 
PRINCIPLES. 23 
 
 produced by a solution containing i gram of the sub- 
 stance in i c.c. examined in a column one decimeter long. 
 It is usually represented by the symbol []. To indicate 
 the light employed in the observation, [] D or []j is used. 
 D stands for light of wave length corresponding to the D 
 line of the solar spectrum (sodium flame) and j (jaune) 
 for the transition tint, which in the case of sugar solutions 
 furnishes results corresponding to the "mean yellow 
 ray." It is usual also to indicate in the same symbol the 
 temperature of observation; thus, [] 2 . 
 
 Under ordinary methods of observation the specific rota- 
 tory power is represented by the following formula: 
 
 r -, 100 a - i 1 
 
 [a] D = ; in which 
 
 [] D is the specific rotatory power for the light of the sodium flame, 
 a is the angular rotation observed, 
 
 c is the concentration expressed in grams per 100 c.c. of liquid, 
 / is the length of the tube in decimeters. 
 
24 ORGANIC CHEMISTRY. 
 
 DERIVATIVES AND SYNTHETIC COMPOUNDS. 
 
 The list of substances designated organic is increased by 
 transformation of natural compounds and by formation of 
 compounds from simpler bodies or elements. The latter 
 method is called "synthesis." 
 
 Transformations. Many methods are known. The fol- 
 lowing are of frequent use: 
 
 HEAT. Many organic bodies melt at a moderate heat 
 and at a higher point volatilise unchanged. The effect is 
 usually termed distillation if the substance is a liquid, and 
 sublimation if a solid. Some substances can be melted 
 but not volatilised except by decomposition; a few pass 
 apparently directly from the solid to the gaseous condition. 
 When a high heat is applied many organic bodies undergo 
 irregular decomposition by which a mixture of new com- 
 pounds is obtained, none of the original body distilling. 
 This is termed " destructive distillation." It is applied 
 largely to wood and natural bituminous substances (coal 
 and shale), and is the source of many valuable compounds. 
 
 Destructive distillation may be illustrated by heating a few 
 pieces of wood or a fragment of soft coal in a small testtube. Com- 
 bustible vapors are given off and tar is deposited on the cooler 
 part of the tube, If a few fragments of bone or glue be heated, 
 offensive vapors will be emitted, due principally to the nitrogen 
 compounds present. 
 
 The extent of decomposition and the substances formed 
 in destructive distillation being dependent on several condi- 
 tions, no general reaction can be given. In a few instances 
 
DERIVATIVES AND SYNTHETIC COMPOUNDS. 25 
 
 the action is definite. When pyrotartaric acid is heated 
 for some time above 200, it decomposes as follows: 
 
 Pyrotartaric acid Butyric acid Carbon dioxide. 
 
 C 5 H 8 4 C 4 H 8 2 + C0 2 
 
 OXYGEN. Most organic bodies when exposed to the 
 action of oxygen at high temperature burn, the carbon 
 forming carbon dioxide and the hydrogen forming water. 
 Nitrogen may be liberated in the free state or in the form 
 of hydrogen compounds. Sulphur and phosphorus are 
 oxidised. At low temperatures, free oxygen acts on but 
 few substances, but by the use of oxidising agents different 
 effects may be obtained according to the conditions of the 
 action. Oxygen may be added to the molecule, hydro- 
 gen may be removed without addition of oxygen, or oxygen 
 may be substituted for hydrogen in the proportion of 
 O for H 2 . The following reactions illustrate these actions: 
 
 Alcohol Aldehyde. 
 
 C 2 H 6 O + O C 2 H 4 O + H 2 O 
 
 Aldehyde Acetic acid. 
 
 C 2 H 4 + O C 2 H 4 2 
 
 Alcohol Acetic Acid. 
 
 C 2 H 6 + 2 C 2 H 4 2 + H 2 
 
 Whether aldehyde or acetic acid is formed in one reaction 
 from alcohol, depends on the energy of the oxidising agent. 
 
 SO-CALLED NATURAL CHANGES. The principal of these 
 are Fermentation, Putrefaction and Decay. 
 
 FERMENTATION and PUTREFACTION, are processes by 
 which organic bodies are converted into new substances 
 simpler in composition. They are dependent on the action 
 of minute organisms and enzyms. Substances that pre- 
 vent these actions are called antizymotics . 
 
 Some important forms of fermentation are: 
 
26 ORGANIC CHEMISTRY. 
 
 1. The Vinous, producing alcohol, C 2 H 6 O, and carbon 
 dioxide, CO 2 . 
 
 2. The Acetous, producing chiefly acetic acid, C 2 H 4 O 2 . 
 
 3. The Lactic, producing chiefly lactic acid, C 3 H 6 O 3 . 
 
 4. The Butyric, producing chiefly butyric acid, C 4 H 8 O 2 . 
 Each fermentation is dependent upon and produced by 
 
 special enzyrns, which are often the products of particular 
 forms of microorganisms. 
 
 PUTREFACTION is usually limited to changes in nitrog- 
 enous bodies. The more complex forms of these contain 
 sulphur and phosphorus, which are converted into gaseous 
 compounds of offensive odors. 
 
 These transformations are largely by hydrolysis, but 
 other actions , especially oxidation , occur . The products will 
 differ according as the action occurs in the presence of air 
 (aerobic) or out of contact of air (anaerobic). Substances 
 that prevent the growth of microorganisms or the action of 
 their enzyms will prevent putrefaction and are termed 
 antiseptics. 
 
 DECAY. This is the decomposition of organic bodies by 
 the slow action of oxygen. It takes place too slowly for 
 any increase of temperature to be noticed, and it is rarely 
 complete, that is, some portions of the elements escape 
 action. When wood burns with a flame it leaves nothing 
 but the incombustible mineral matter or ash, but when 
 it decays a brown powder is left, which contains some of the 
 original carbon and hydrogen. Decay requires the access 
 of air, the presence of moisture and a temperature above 
 the freezing point. 
 
 HYDROLYSIS. This term is applied to transformations 
 accompanied by the taking up of water with production 
 of one or more substances, in which neither water nor the 
 original body remains. It is brought about by action of 
 
DERIVATIVES AND SYNTHETIC COMPOUNDS. 27 
 
 enzyms, dilute acids or acid salts. The manner in which 
 the hydrolysing body acts is not understood; it is usually 
 not permanently affected by the reaction that it produces. 
 These reactions take place only in the presence of excess of 
 water, but usually the equation is written without the 
 hydrolysing agent or the excess of water, since these are 
 unchanged. Thus, the hydrolysis of cane sugar is written 
 
 C 12 H 22 O n + H 2 == 2C 6 H 12 6 
 
 although the hydrolysing agent and much additional water 
 are present. 
 
 DEHYDROLYSING AGENTS. These are commonly called 
 dehydrating agents, but the latter term should be applied 
 only to substances that remove water existing as such from 
 other bodies. Anhydrous copper sulphate and calcium 
 chloride, for example, are used in the preparation of 
 absolute alcohol to remove the small amount of admixed 
 water that cannot be removed by distillation. The true 
 dehydrolysing agents (many of which are also dehydrating 
 agents) remove hydrogen and oxygen in the proportion of 
 H 2 to O, and form water, although the water-molecule does 
 not exist in the original substance. In many cases an 
 intermediate combination is produced that breaks up 
 yielding water. For an illustration of this, see the process 
 for making ether. 
 
 When cane sugar is mixed with strong sulphuric acid, 
 water is formed, which unites with the acid, and carbon is 
 set free. Among the most used dehydrolysing agents are 
 sulphuric acid, phosphoric anhydride and zinc chloride. 
 Heat often acts as a dehydrolysing as well as a dehydrating 
 agent. 
 
 NITRIC ACID. The action of this differs with the tem- 
 perature and degree of concentration. When strong cold 
 
28 ORGANIC CHEMISTRY. 
 
 acid is used, a substitution of NO 2 for H usually occurs, 
 producing " nit ro -compounds." When the acid is weak 
 or hot a direct addition of oxygen may take place, accord- 
 ing to methods noted in a preceding paragraph. An 
 illustrative reaction of the formation of nitro-com- 
 pounds is: 
 
 C 6 H 6 + HN0 3 = C 6 H 5 N0 2 + H 2 O 
 
 CHLORINE, BROMINE AND IODINE. These sometimes 
 form compounds by addition, but more frequently sub- 
 stitute hydrogen or other monads. In structural formulas, 
 they are generally in direct association with carbon. The 
 following are illustrative reactions for additive and sub- 
 stitutive actions: 
 
 Additive Benzene dichloride. 
 
 C 6 H 6 + C1 2 = C 6 H 6 C1 2 
 
 Substitutive Dichlorbenzene. 
 
 C 6 H 6 + C1 4 = C 6 H 4 C1 2 + 2HC1 
 
 SODIUM AND POTASSIUM. These expel hydrogen, atom 
 for atom, when it is in the hydroxyl position. An illus- 
 trative reaction is : 
 
 Alcohol Sodium ethylate. 
 
 C 2 H 5 HO + Na = C 2 H 5 NaO + H 
 
 SULPHURIC ACID. The action of this as a dehydrolysing 
 agent, in which respect it is very powerful, has already 
 been noted. Acting on bodies that contain no oxygen or 
 closed-chain compounds, with or without oxygen, sulphuric 
 acid displaces an atom of hydrogen by substituting the 
 molecular residue, HSO 3 forming a molecule of water at the 
 same time. The substitutions thus obtained are termed 
 
DERIVATIVES AND SYNTHETIC COMPOUNDS. 29 
 
 "sulphonic acids." The following reaction illustrates 
 their formation: 
 
 Benzene Benzene sulphonic acid. 
 
 C 6 H 6 + H 2 S0 4 = C 6 H 5 HS0 3 + H 2 O 
 
 By duplication of the reaction, poly sulphonic acids 
 (di, tri, etc.) may be obtained. In many cases sulphuric 
 acid exchanges one or both of its hydrogen atoms for 
 hydrocarbon radicles, producing esters. 
 
 Dilute sulphuric acid often produces hydrolysis, being 
 itself unaffected by the reaction. 
 
 FRACTIONAL DISTILLATION. When a liquid contains two 
 or more substances of different boiling points, a partial 
 separation of these may be made by distillation, changing 
 the receiver from time to time. Each liquid distils over 
 at about its boiling point. The most volatile constituent 
 distils first and as each constituent passes off, a thermom- 
 eter immersed in the vapor shows steadily rising tempera- 
 ture. The separate portions are termed fractions. It is 
 usually not possible to separate compounds completely by 
 this method. The adhesion between liquids and vapors 
 causes some of the material of higher boiling point to be 
 carried over at a lower temperature. Thus, a mixture of 
 common alcohol and water can be distilled so as to reduce 
 the amount of water to about 5 per cent, of the distillate, 
 but absolute alcohol cannot be so obtained. 
 
 Fractional distillation is largely used in the separation 
 of the hydrocarbons of petroleum and coal-tar. 
 
 LIGHT AND ELECTRICITY. Many organic bodies are 
 affected by light, but the action is usually superficial un- 
 less fresh portions are constantly exposed. A mixture of 
 gelatin and potassium dichromate is rendered insoluble, 
 
30 ORGANIC CHEMISTRY. 
 
 and commercial betanaphthol is slowly darkened by light. 
 The other forms of radioactivity probably also cause 
 changes. 
 
 Electricity produces combination and decomposition of 
 organic bodies. Electrolysis can be obtained with many 
 compounds. By passing continuous or interrupted 
 discharges from carbon poles in contact with some gases 
 synthetic actions may be obtained. 
 
 STRUCTURE OF ORGANIC MOLECULES. 
 
 Percentage Composition and Formula. The com- 
 position of any substance may be expressed without use 
 of symbols, or indication of the number of atoms of 
 the elements present. The parts by weight of each ele- 
 ment contained in one Hundred parts of the substance may 
 be given. The composition of ordinary sugar may be 
 stated as: 
 
 Carbon 42.1 
 
 Hydrogen 6.4 
 
 Oxygen 51.5 
 
 These figures represent percentage composition. 
 
 Such methods of expression, though simple and repre- 
 senting facts alone, are not convenient. No satisfactory 
 comparison as to the composition of different compounds 
 can be reached except by the construction of formulas 
 in which the elements are represented by the relative 
 numbers of atoms probably present. 
 
 By dividing each figure by the atomic weight of the 
 element, and clearing of fractions, as nearly as can be done 
 
MOLECULAR STRUCTURE. 31 
 
 conveniently, the number of atoms of each element will 
 be obtained. For example: 
 
 42.11 -v- 12 = 3.51 X 3-4 = n-93 
 
 6.43 -r- i = 6.43 X 3-4 = 21.8 
 51.56 -T- 16 = 3.24 X 3-4 = ii. 01 
 
 The last column indicates the formula, C 12 H 22 O n ; that 
 is, this formula, when calculated to percentage composi- 
 tion, will give figures practically identical with those 
 actually obtained by analysis of a sample of cane sugar. 
 
 It is evident that any multiple of this formula would 
 also correspond to the percentage composition, hence it is 
 necessary to fix the numbers more rigidly. The lowest 
 term is by no means always the proper formula. The 
 following list exemplifies this. Each formula is correct 
 only for the body indicated; a multiplication or division 
 of it is inaccurate. 
 
 Molecular weight. 
 
 Formaldehyde CH 2 O 30 
 
 Acetic acid C 2 H 4 O 2 60 
 
 Lactic acid C 3 H 6 O 3 90 
 
 Tetrose C 4 H 8 O 4 120 
 
 Arabinose C 5 H 10 O 5 150 
 
 Dextrose C 6 H 12 O 6 180 
 
 Mannoheptose C 7 H 14 O 7 210 
 
 The formula is fixed in each case by the molecular 
 weight. The determination of this becomes, therefore, an 
 important matter. Several methods are in use : among the 
 most frequently employed are determinations of vapor 
 density, freezing point of solution and combining weight. 
 The procedures for the first two are described in connec- 
 tion with determination of physico-chemical data. 
 
 Vapor Density. This method of ascertaining molecular 
 weight is of wide application and great value. Its use 
 
32 ORGANIC CHEMISTRY. 
 
 depends upon the fact that when a substance is capable 
 of volatilising without decomposition, the density of its 
 vapor compared to hydrogen as unity will be half the 
 molecular weight. 
 
 For example: One liter of vapor of common ether is 
 37 times as heavy at i liter of hydrogen gas, the conditions 
 of temperature and pressure being the same. The molec- 
 ular weight of ether will be, therefore, 74. This corre- 
 sponds to the formula C 4 H 10 O. (C 4 =48; H 10 =io; O = i6 
 = 74). No multiple of this formula will correspond to the 
 observed vapor-density. The further elucidation of this 
 formula, expressing its rational form (C 2 H 5 ) 2 O, is attained 
 by other methods. 
 
 All the members of the homologous series of hydrocar- 
 bons, beginning with CH 2 , have the same percentage 
 composition, their formulas being multiples of the lowest 
 formula, but the vapor densities steadily increase as shown 
 in the annexed table (CH 2 has not been obtained). 
 
 Formula. 
 
 C 2 H 4 . . . 
 
 Density. 
 14 
 
 Molecular weight. 
 28 
 
 
 2 I 
 
 42 
 
 C.Ho 
 
 . . .. 28 
 
 S6 
 
 
 r< 
 
 70 
 
 The exact formula of each member of the series can 
 be fixed by a determination of the molecular weight. 
 
 Many organic bodies are decomposed by heat and their 
 vapor density cannot be obtained. 
 
 Freezing Point of Solution. The general rule is that 
 when different substances are dissolved in amount propor- 
 tional to their molecular weights in separate portions of the 
 same solvent, the depression of the freezing point is the 
 same. Experiment has shown that if the dissolved 
 
MOLECULAR STRUCTURE. 33 
 
 substance and the solvent are in the ratio of i molecule 
 of the former to TOO molecules of the latter the depression 
 of the freezing point of the solvent will be 0.62. The 
 method is not widely applicable, being satisfactory only 
 with substances of low chemical activity. Active bodies, 
 such as acids, bases or salts, give abnormal results. 
 
 Combining Weight. If an organic body forms a definite 
 compound with any element or with any compound, the 
 molecular weight of which is known, such combination can 
 be utilized in determining the molecular weight. For 
 example, silver oxide reacts with acetic acid to form 
 silver acetate and water. Silver acetate has the per- 
 centage composition: 
 
 Silver 64.6 
 
 Carbon 14.4 
 
 Hydrogen 1.8 
 
 Oxygen 19.2 
 
 Proceeding as indicated on page 31, that is, dividing 
 each percentage by the corresponding atomic weight and 
 multiplying these quotients by a number which will 
 practically eliminate fractions (in this case 1.66), the 
 following figures are obtained: 
 
 64.6 -f- 108 = 0.6 X 1.66 = Q-99 
 
 14.4 -7- 12 = 1.2 X 1.66 = 1.99 
 
 1.8 -r- i = 1.8 X 1.66 = 2.98 
 
 19.2 -T- 16 = 1.2 X 1.66 = 1.99 
 
 The ratio of the numbers in the last column is sub- 
 stantially 1:2:3:2, hence the formula of silver acetate is 
 AgC 2 H 3 O 2 . Here, as in the instance explained on page 31, 
 any multiple of the formula, for example, Ag 2 C 4 H 6 O 4 , 
 3 
 
34 ORGANIC CHEMISTRY. 
 
 would satisfy the percentage composition. This uncer- 
 tainty is eliminated by determining the degree of basic 
 power of acetic acid. If it is a monobasic acid silver 
 acetate will have but one atom of silver; if a dibasic 
 acid then the 'salt will have two atoms of silver. Ex- 
 periment shows that acetic acid forms but one series of 
 salts, hence silver acetate must be AgC 2 H 3 O 2 , and acetic 
 acid C 2 H 4 O 2 . The latter formula can be confirmed by a 
 determination of the vapor density. 
 
 Several other methods for determining molecular 
 weight are known, but do not need description here. 
 Many organic bodies exist to which no known method is 
 applicable; hence the formula is not definitely assigned. 
 Starch, for example, has a percentage composition corre- 
 sponding to the ratio C 6 H 10 O 5 , but the molecular weight 
 cannot be ascertained by any of the methods available. 
 The origin and transformations of starch suggest complex 
 structure; it is probable that C 60 H 100 O 50 is an approxima- 
 tion to its formula. In such cases the formula is often 
 expressed in the lowest terms with a provisional indefinite 
 coefficient, thus wC 6 H 10 O 5 . 
 
 Empirical, Rational and Structural Formulas. The for- 
 mulation of organic molecules -is based upon the as- 
 sumption that the valencies of the principal elements are 
 not subject to irregularity. Carbon is always taken as a 
 tetrad, hydrogen as a monad, oxygen as a dyad and 
 nitrogen as either triad or pentad. Phosphorus is usually 
 considered as a pentad; sulphur as either a dyad or hexad. 
 It is, however, freely assumed that polyvalent elements 
 may combine by more than one bond to another atom, 
 even another of the same nature. Thus carbon is as- 
 sumed to be capable of forming the groups: 
 =C C= = C = C = C-C 
 
MOLECULAR STRUCTURE. 35 
 
 Oxygen is frequently represented as combining by both 
 its bonds, as in the group: H-O-C = O. The double and 
 triple linkings are often termed "unsaturated." 
 
 It must not be supposed that a linking by two bonds 
 is a stronger union than by one bond. Valency is a 
 standard of capacity of affinity, not of intensity; in fact, 
 acetylene which is supposed to contain the triple linking 
 is more easily decomposed than ethane in which the single 
 linking is assumed. 
 
 H H 
 
 H C=C H H C C H 
 
 I I 
 H H 
 
 Acetylene Ethaoe 
 
 Some recent researches have shown the existence of 
 compounds in which carbon is apparently a triad, and 
 others in which oxygen is apparently a tetrad, but the 
 theories in regard to valency are provisional only. For 
 the great majority of organic compounds, the valencies 
 noted above are satisfactory. 
 
 A formula that shows only the number of atoms of each 
 element in the compound is an empirical formula; if 
 any supposed arrangement is exhibited the formula is 
 termed rational. When the symbols are displayed so 
 as to indicate probable relations of the atoms to each other 
 the formula is termed structural (sometimes graphic}. The 
 following formulas exemplify these terms : 
 
 Empirical. Rational. Structural. 
 
 H H 
 
 C 2 H (1 O C 2 H 5 HO H C C OH 
 
 -I I 
 H H 
 
36 ORGANIC CHEMISTRY. 
 
 Some authorities distinguish between empirical and 
 molecular formulas, applying the former term to the sim- 
 plest formula that corresponds to the percentage composi- ' 
 tion, and the latter term to formulas that correspond to 
 the molecular weight. Under this distinction, CH 2 O would 
 be the empirical formula of all the bodies in the list on 
 page 31 and would be the molecular formula of formalde- 
 hyde only. In this work, the terms will be used synony- 
 mously. 
 
 In some substances the atoms are subject to changes of 
 position without altering the identity of the substance. 
 Thus phloroglucol, C 6 H 6 O 3 , can be represented by either 
 of the following formulas : 
 
 Symmetric trihydroxybenzene. Triketohexamethene. 
 
 C 6 H 3 (HO) 3 (CH 2 ) S (CO), 
 
 Molecules that exhibit this variability are termed 
 tautomeric or, rarely, desmotropic. 
 
 A general formula is an algebraic expression for repre- 
 senting the formulas of a group of bodies, for illustration 
 of which see "Homologous Series." 
 
 Ordinary structural formulas represent the atoms 
 arranged upon the same plane, but as molecules occupy 
 space it is desirable to formulate them on a three-dimen- 
 sional system. As a basis for this, the carbon atom is 
 represented as a tetrahedron. It is not assumed that this 
 is the shape of the atom, but the four apexes of this solid 
 correspond to the four valencies usually manifested by 
 carbon. Such formulas are termed " sfereochemic" They 
 are most satisfactorily shown by models, but the annexed 
 figures show the usual methods of exhibiting them. 
 
MOLECULAR STRUCTURE. 
 
 OH OH 
 
 37 
 
 cojr 
 
 OH 
 
 LH 
 
 A 
 
 Dextrolactic acid 
 
 OH 
 I 
 . C II 
 
 A 
 
 HOOC CH 3 
 Levolactic acid 
 
 Union of carbon atoms by two bonds is shown by join- 
 ing the tetrahedrons by edges (see page 40) ; union by 
 three bonds, by joining them by faces. 
 
 Optical Activity. Asymmetric Atoms. Optical activ- 
 ity is the power to rotate polarised light. It is possessed 
 by many bodies, but in organic chemistry is of importance 
 only when exhibited by substances in liquid form, by 
 fusion or solution. The rotation may be either to the 
 right or left. Substances exhibiting the former action are 
 termed dextrorotatory, indicated by + or d; substances 
 showing left-handed rotation are termed levo- (laevo) 
 rotatory, indicated by or 1. 
 
 Asymmetric Atoms. Any atom that has each of its 
 bonds united to an atom or molecule of different nature is 
 asymmetric. Asymmetric carbon is the most important 
 example. In structural formulas, it will be indicated by 
 an italic symbol. (See, for example, the formula of tar- 
 taric acid, page 88.) 
 
 A general relation exists between this position of the 
 carbon atom and the optical activity, expressed by the rule 
 
38 ORGANIC CHEMISTRY. 
 
 that "every carbon compound that, in the liquid con- 
 dition, rotates polarised light, will have in its molecule at 
 least one atom of asymmetric carbon." The reverse 
 of the proposition is not true. Asymmetric carbon may be 
 present in substances that do not rotate polarised light. 
 In fact, in most cases, molecules containing asymmetric 
 carbon exist in three conditions, dextro- and levorotatory, 
 and inactive. The inactive condition may depend upon 
 either the antagonistic influence of the asymmetric carbon 
 atoms within the molecule (neutralisation by internal 
 compensation) or by the presence of equivalent quantities 
 of the opposing active substances (neutralisation by 
 external compensation). 
 
 The dibasic acid represented by the empirical formula 
 C 4 H 6 O 6 exists in four forms, each of which has the rational 
 formula H 2 C 2 H 4 O 6 . 
 
 Ordinary tartaric acid .... Dextrorotatory. 
 
 Levotartaric " ... .Levorotatory. 
 
 Racemic ' .... Inactive. (Mixture of + and .) 
 
 Mesotartaric " ... .Inactive. (Not a mixture.) 
 
 In racemic acid the neutralisation is due to presence of 
 equivalent amounts of the + and forms, in mesotartaric 
 acid to the existence of antagonistic asymmetric carbon 
 atoms. The latter condition cannot exist in bodies having 
 but one asymmetric carbon atom in the molecule. The 
 association of molecules of opposing optical conditions is 
 termed "racemism." 
 
 Isomerism, Metamerism and Polymerism. The proper- 
 ties of bodies depend on the elements present in them 
 and the arrangements of these elements with respect to 
 each other. Different arrangements may be made with 
 the same constituent atoms, and thus will arise bodies 
 
MOLECULAR STRUCTURE. 39 
 
 having the same constitution but not identical. To all 
 such instances the term isomeric is often applied, but it 
 is more satisfactory to limit it to the instances in which 
 the bodies are analogous in structural formula. When 
 the identity is in percentage composition and in molecular 
 weight, the structures being of different types, the term 
 metameric is applicable. When the identity is in percent- 
 age composition, the molecular weights being multiples, 
 but the structure analogous, the relation is termed poly- 
 meric. True isomerism is often indicated by the addition 
 of the prefix "iso" to the name of one of the substances. 
 Polymerism is sometimes indicated by the similar addition 
 of ''para" to one of the names. The following illustrations 
 will show the application of these principles: 
 
 True isomerism. 
 H C^N cyanogen. C = N H isocyanogen. 
 
 Metamerism. 
 (CH 3 ) 2 O methyl oxide. C 2 H 5 HO alcohol. 
 
 Polymerism. 
 C 2 H 4 O aldehyde. C 6 H 12 O 3 paraldehyde. 
 
 Instances of isomerism dependent on slight differences in 
 the spatial relation of the constituent atoms are frequently 
 observed in complex molecules. These can only be shown 
 by stereochemic formulas. The term " allo -isomerism" 
 proposed for this phase, has not been generally adopted, 
 the usual designation is "stereochemic isomerism." The 
 distinctive nomenclature of these isomers is incomplete. 
 One of the methods is shown in the annexed formulas, in 
 each of which a pair of double-linked carbon atoms are 
 shown by tetrahedrons joined by edges. 
 
40 ORGANIC CHEMISTRY. 
 
 Maleic acid Fumaric acid 
 
 Plane symmetric Axial symmetric 
 (or cis-) form (or trans-) form 
 
 The syllables "cis" and "trans" are used because, in one 
 case, the similar radicles are on the same side of the carbon 
 chain, in the other case on opposite sides. 
 
 Organic Radicles. Any unsaturated molecule may be 
 considered a radicle, and hence the number of radicles in 
 the formula of any body will be limited only by the number 
 of divisions that may be assumed. Many of the groupings 
 thus obtained, having no coherence or independent 
 function, are not regarded. Any grouping that confers 
 characteristic properties or reactions upon the molecule or 
 that remains unchanged through a series of reactions, 
 is a true radicle. Some of these are of frequent occurrence, 
 are always distinguished in rational formulas and often* 
 indicated in the name of the compound. The following 
 are instances: 
 
 HO, Hydroxyl. The hydrogen of this is easily replaceable 
 by positive elements such as potassium and sodium. 
 When subjected to the action of certain chlorine com- 
 pounds the entire group is replaced, not the hydrogen 
 alone, as occurs when hydrogen is united to carbon. The 
 presence of one or more hydroxyl groups in a compound 
 is often indicated by the termination "ol," e.g., phenol, 
 C 6 H 5 HO. 
 
 HOCO, Carboxyl. This confers acid properties upon the 
 
MOLECULAR STRUCTURE. 41 
 
 molecule containing it. The basic capacity is proportional 
 to the number of such groups present. Thus acetic acid 
 has but one carboxyl group and is monobasic; tartaric 
 acid has two and is dibasic; citric acid has three and is 
 tribasic. 
 
 HCO, Aldehyde Group. The hydrogen is joined to the 
 carbon atom and is not replaceable by positives. Com- 
 pounds containing this group generally show reducing 
 power. 
 
 Ketonic Group. Carbon united to oxygen by two 
 
 bonds and by its remaining bonds to carbon atoms that 
 are not united to a negative body. This group generally 
 confers reducing power on the molecule containing it. 
 
 The foregoing groups, it will be noted, do not contain 
 asymmetric carbon and, therefore, do not produce optical 
 activity. 
 
 NH 2 , Amidogen. This generally confers capacity for 
 combining with acids which is often proportional to the 
 number of groups present. It is indicated by the syllables 
 "amin" or "amid." 
 
 NH, Imidogen. This resembles in function amidogen. 
 It is indicated by the syllables "imin" or "imid." 
 
 Homologous Series. Any series of compounds in which 
 the formulas differ by CH 2 or some multiple of this differ- 
 ence by a whole number, is termed a homologous series, 
 and the members thereof are homologues. These terms 
 are not limited to hydrocarbons. The following are exam- 
 ples of homologous series: 
 
42 ORGANIC CHEMISTRY. 
 
 Paraffins. Alcohols. Esters. 
 
 CH 4 CH 3 HO (CH 3 ) 2 SO 4 
 
 C 2 H 6 C 2 H 5 HO (C 2 H 5 ) 2 S0 4 
 
 C 3 H 8 C 3 H 7 HO (C 3 H 7 ) 2 S0 4 
 
 C 4 H 10 C 4 H 9 HO (C 4 H 9 ) 2 S0 4 
 
 In the third column the constant difference is (CH 2 ) 2 , 
 but the series is still homologous. A series intermediate 
 between each member is known, but even if these latter 
 were non-existent, the homology would not be lost. 
 
 General Formulas. The existence of homologous series, 
 renders it possible to express by one formula the molecule 
 of any member of the group. Thus, in the first series, the 
 atoms of hydrogen are always two more than twice the 
 carbon atoms. The general formula, C n H 2n + 2 , in which n 
 represents any number of atoms, will stand for any member 
 of this series. If it be required, for instance, to write the 
 formula of the sixth member the rule is simple. As the 
 carbon increases regularly one atom at a time, the sixth 
 member will have C 6 . Twice six plus two is fourteen; 
 the formula is, therefore, C 6 H 14 . The general formula 
 of the second series above given is C n H 2n+1 HO; of the 
 third series (C n H 2n+1 ) 2 SO 4 . 
 
 These formulas are sometimes used instead of the series- 
 names. Thus the series beginning with CH 4 is often des- 
 ignated as the series C n H 2n+2 . 
 
 Carbon Chains. The valency of each member of 
 a homologous series is the same. The explanation of this 
 is the supposition that, in forming the molecules, the carbon 
 has in part satisfied itself, so that each atom of carbon 
 added carries into the molecule only two degrees of valency, 
 which H 2 satisfies. Structural formulas will exemplify 
 this supposition. 
 
CALIFORNIA COLLESi 
 
 of Ph'ARMAPV 
 
 MOLECULAR STRUCTURE. 43 
 
 Methane, CH 4 . Ethane, C 2 H 6 . Propane, C 3 H 8 (tritane). 
 
 H H H H H H 
 
 H C H H C C H H C C C H 
 
 H H H H H H 
 
 These linked carbon atoms have been called, somewhat 
 fancifully, perhaps, ''carbon skeletons." The forms shown 
 above are termed "open chains." In other cases the 
 carbon is arranged in a ring of three or more atoms forming 
 " closed chains " 
 
 Properties of Bodies in the Homologous Series. The 
 relation of homologous bodies is not a mere accidental 
 relation in formulas. By comparing different members 
 of the same series analogies either in origin, .general 
 properties, or chemical relations appear. The series 
 beginning with CH 4 is characterised by general indifference 
 to chemical action. The hydroxides of the series be- 
 ginning with CH 3 HO constitute a series of alcohols which 
 possesses specific physiologic action. In each series 
 fusing and boiling points, specific gravity and other 
 constants vary with considerable regularity. The molec- 
 ular weight, of course, increases regularly. 
 
 Isomeric Modification in Homologous Series. Many or- 
 ganic bodies occur in two or more forms not sufficiently 
 distinct to consider them as essentially different, and yet 
 not identical. In such cases, the diagrammatic method 
 of showing the linking of the carbon atoms may be utilised 
 to show that the difference may be due to different positions 
 of the carbon atoms, with respect to each other and to the 
 other elements present. When the number of carbon 
 atoms is less than four, fundamental variation of the 
 
44 ORGANIC CHEMISTRY. 
 
 structure is not possible, except by closing the chain, as 
 shown below: 
 
 I I V 
 
 vith C C 
 
 C C C is identical with C C but not with C 
 
 III 'I A 
 
 -C C-C 
 
 I I I 
 
 With four carbon atoms two forms may be obtained, 
 as exemplified in the hydrocarbon, C 4 H 10 : 
 
 H H H H H H H 
 
 I I I 
 H C C C H 
 
 H H H H 
 
 H C C C C H H C C C- 
 
 I I I I III 
 
 H H 
 
 H C H 
 
 A 
 
 Normal butane Isobutane (methyl propane) 
 
 The number of possible variations increases rapidly 
 with the number of carbon atoms, so that the higher 
 members of the series show numerous instances. The 
 structural formulas given above may be condensed as 
 follows : 
 
 Normal butane. Isobutane. 
 
 CH 3 CH 2 CH 2 CH 3 CH 3 CH(CH 3 )CH 3 
 
 CLASSIFICATION AND NOMENCLATURE OF ORGANIC 
 COMPOUNDS. 
 
 Many organic bodies are, in formulas, structurally 
 analogous to inorganic bodies, and may be classified and 
 named on the same systems as used in inorganic chemistry. 
 The groups termed acids, alkalies and salts, are well 
 represented in organic chemistry. Oxides, sulphides and 
 halogen compounds are also abundant. The phenomena 
 
CLASSIFICATION. 45 
 
 of isomerism, polymerism, tautomerism and homology are 
 practically peculiar to organic chemistry, and hence the 
 methods of classification and nomenclature must be much 
 more elaborate. Unfortunately the systems of naming 
 and arranging organic compounds are still incomplete and 
 unsatisfactory. 
 
 In classifying organic bodies it is most convenient to 
 begin with the binary forms the hydrocarbons. These 
 are very numerous and cannot be named according to 
 their formulas, as is so easily done with binary inorganic 
 compounds. Each hydrocarbon has a name referring to 
 some property, source, use or other incidental, often 
 fanciful, relation. 
 
 Thus methane, CH 4 , the fundamental hydrocarbon of 
 organic chemistry, because the simplest of all known ones 
 in structure, was called marsh gas, because it was detected 
 in the emanation from the mud of marshes. The name, 
 methane, is due to the relation of the hydrocarbon to 
 methyl alcohol and that name, in turn, is really a mis- 
 nomer, for it refers to a Greek word meaning "wine," to 
 which methyl alcohol has no direct relationship. Sim- 
 ilarly the hydrocarbon, butane, is so named owing to its 
 structural relations to butyric acid, which is obtained 
 from butter. " Butyric " is derived from the Greek word 
 for butter. 
 
 Suggestions have been made to name compounds by 
 syllable systems, according to which the elements should 
 be indicated by their symbols and the number of atoms in 
 each by the vowels in the usual alphabetic order, i. e., 
 a = i; e=2, etc. By this system CH 4 would be "Caho." 
 These methods have not received serious attention, as they 
 produce jargon. 
 
 Nomenclature in organic chemistry is in the main based 
 
46 ORGANIC CHEMISTRY. 
 
 on the principle that the name shall show the molecular 
 structure or immediate relationships of the body. It is not 
 usual to base it on properties, but two well-marked in- 
 stances of this are to be noted. Nitrogenous organic bodies 
 termed "enzyms" or "non-organised ferments" are 
 generally distinguished by the termination "ase." Ni- 
 trogenous bases are distinguished by the termination 
 "ine." Many substances are as yet not definitely classi- 
 fiable. For these the termination "in" is provisionally 
 used. 
 
 The following is a summary of the principal groups of 
 organic bodies: 
 
 Hydrocarbons. 
 
 Ethers, Alcohols, Aldehydes, Ketones, Esters. 
 
 Oils and Fats. 
 
 Acids and Salts. 
 
 Carbohydrates. 
 
 Cyanogen and derivatives. 
 
 Amine and derivatives. 
 
 Alkaloids, Ptomaines and Leucomaines. 
 
 Azo-, Diazo- and Hydrazo-compounds. 
 
 Proteids. 
 
 Enzyms. 
 
 The distinction between the groups is not well defined; 
 many bodies may be included in more than one group, 
 their molecules exhibiting mixed structure. Thus lactic 
 acid has alcoholic as well as acidic structure. Dextrose 
 which is classed among the carbohydrates has alcoholic 
 and aldehydic structure. 
 
 Organic compounds are sometimes divided into two 
 groups, termed respectively: 
 
 (i) Open-chain or aliphatic compounds, and (2) closed- 
 
NOMENCLATURE. 47 
 
 chain or cyclic compounds. This division is also imper- 
 fect, in that many bodies cannot be assigned positively to 
 either group. 
 
 Organic compounds that show analogy to inorganic 
 compounds may be designated by analogous terms. Thus, 
 the formula of common alcohol may be written C 2 H 5 HO, 
 showing a structural analogy to KHO. C 2 H 5 is called 
 ethyl, hence alcohol is termed ethyl hydroxide. 
 
 To assist in distinguishing organic bodies, many syllables 
 have been applied as prefixes or suffixes. A few examples 
 of the more important will be here given. Other less 
 important ones will be mentioned in connection with the 
 compounds that exemplify the use. 
 
 "Ane," "ene," "ine," "one," etc., are used for different 
 series of hydrocarbons. The system may be extended by 
 using other vowels and diphthongs. In these syllables the 
 first vowel is long. Care must be taken not to confuse 
 these terminations with others apparently similar, namely 
 "one" used to indicate a special form of oxygen compound, 
 called a ketone, and the use of "ine" (in which "i" is short) 
 as a termination for basic substances. 
 
 "ase" indicates an enzym; 
 
 "ose" indicates a carbohydrate, but is also applied to 
 some intermediate products of proteid hydrolysis; 
 
 " ol " indicates hydroxyl ; 
 
 " yl " indicates a radicle, generally one of uneven valency ; 
 
 "in" has no exact significance; it is employed largely 
 for bodies not definitely classifiable. It is used for some 
 common enzym, but it would be best to use the proper 
 termination for these ; 
 
 "al" indicates an aldehyde; 
 
 "mono," "di," "tri," etc., are used with analogous 
 significance to that in inorganic chemistry; 
 
48 ORGANIC CHEMISTRY. 
 
 "nitro," "chloro," "bromo," "iodo," refer respectively 
 to the presence of NO 2 , Cl, Br, I; 
 
 "nitroso" indicates the group NO; 
 
 "azo" and "diazo" indicate the group N = N ; 
 
 ' * hydrazo ' ' indicates the group N N = ; 
 
 "amin" or "amid" indicates the group NH 2 ; 
 
 "imin" or "imid" indicates the group NH; 
 
 "thio" indicates sulphur; 
 
 "sulpho" is often used instead of "thio"; 
 
 "pyro" is used to indicate a body that has been ob- 
 tained by heat; 
 
 "sulphonic" indicates the group HSO 3 ; a salt of this, 
 by replacement of H, is a "sulphonate." 
 
DESCRIPTIVE CHEMISTRY. 
 
 Aliphatic or Open-chain Hydrocarbons. 
 
 Compounds of carbon and hydrogen are very numerous. 
 Carbon being a tetrad, the greatest number of atoms of 
 hydrogen that can combine with one of carbon is four. 
 This compound CH 4 , commonly known as methane, is 
 the type of the aliphatic or open-chain hydrocarbons; all 
 other compounds of this class are capable of being re- 
 garded as derived therefrom by subtraction or substitution, 
 or both. 
 
 Substituting all or part of the hydrogen in CH 4 by any 
 other element or group of elements, does not disturb the 
 saturation; the molecule remains a saturated hydro- 
 carbon. Hence the compounds CC1 4 , CHC1 3 , CH 2 C1 2 , 
 CH 3 C1 will all be referable to the same group as CH 4 . 
 
 By successive subtractions of H from CH 4 , are obtained 
 a series of unsaturated molecules, known as radicles, the 
 valency of which will be, in each case, equal to the number 
 of hydrogen atoms removed. CH 3 is a monad radicle 
 because it lacks one atom of hydrogen; CH 2 is a dyad, 
 CH a triad, while C, of course, is a tetrad. From each of 
 these molecules termed hydrocarbon radicles deriva- 
 tives may be obtained, comparable in the main to similar 
 derivatives from the elements themselves. Thus CH 3 
 forms a chloride, bromide, hydroxide, sulphate, each 
 analogous in formula to the similar compound formed by 
 the elements of the potassium group. CH 2 yields com- 
 4 49 
 
50 ORGANIC CHEMISTRY. 
 
 pounds analogous in formulas to those from dyad metals, 
 and so on. In addition these radicles have substitution 
 power, that is, they may replace the hydrogen of other 
 organic compounds. Each of them and each of their 
 derivatives is the first member of a homologous series. 
 A system of nomenclature by terminations has been 
 adopted to distinguish the different series; the vowels are 
 used in regular order, and the syllable yl indicates uneven 
 valency. The number of carbon atoms is indicated, 
 except in the first two members of each series, by syllables 
 formed from Greek numerals. 
 
 The following table will be sufficient to show the prin- 
 ciple of the above classification : 
 
 Series 
 
 Series 
 
 Series 
 
 Series 
 
 Series 
 
 I 
 
 2 
 
 3 
 
 4 
 
 5 
 
 Gen. Formula Gen. Formula 
 
 Gen. Formula 
 
 Gen. Formula 
 
 Gen. Formula 
 
 C n H 2n + 2 
 
 C n H 2n + 1 
 
 C n H 2n 
 
 C n H 2n -, 
 
 C n H 2l ,_ 2 
 
 
 ALKYLS 
 
 
 
 
 
 MONATOMIC 
 
 
 
 
 
 ALCOHOL RAD- 
 
 
 
 
 PARAFFINS 
 
 ICLES 
 
 OLEFINS METHYLENES ACETYLENES 
 
 Methane 
 
 Methyl 
 
 Methene 
 
 Methenyl 
 
 Methine 
 
 CH 4 
 
 CH 3 
 
 CH 2 
 
 CH 
 
 C 
 
 Ethane 
 
 Ethyl 
 
 Ethene 
 
 Ethenyl 
 
 Acetylene 
 
 C 2 H 6 
 
 C 2 H. 
 
 C 2 H 4 
 
 C 2 H 3 
 
 (Ethine) 
 
 
 
 
 
 C 2 H 2 
 
 . Propane 
 
 Propyl 
 
 Propene 
 
 Propenyl 
 
 Allylene 
 
 (Tritane) 
 
 (Trityl) 
 
 (Tritene) 
 
 (Tritenyl) 
 
 (Propine) 
 
 C 3 H 8 
 
 C 3 H 7 
 
 C 3 H 6 
 
 C 3 H 5 
 
 C 3 H 4 
 
 Butane 
 
 Butyl 
 
 Butene 
 
 Tetrenyl 
 
 (Crotonylene) 
 
 (Tetrane) 
 
 (Tetryl) 
 
 (Tetrene) 
 
 C 4 H 7 
 
 Butine 
 
 C 4 H 10 
 
 C 4 H 9 
 
 C 4 H 8 
 
 
 C 4 H 6 
 
 Pentane 
 
 Amyl 
 
 Pentene 
 
 Pentenyl 
 
 (Valerylene) 
 
 C 5 H 12 
 
 (Pentyl) 
 
 C 5 H 10 
 
 C 5 H 9 
 
 Pentina 
 
 Hexane 
 
 Hexyl 
 
 Hexene 
 
 Hexenyl 
 
 Hexine 
 
 C 6 H H 
 
 C 6 H 13 
 
 C 6 H 12 
 
 C 6 H 11 
 
 C 6 H 1Q 
 
PARAFFIN OR METHANE SERIES. 51 
 
 It does not necessarily follow that all of these bodies 
 have been obtained, but most of them are known and the 
 others could doubtless be prepared. The members of 
 each vertical column are homologous with each other. 
 
 The members of the first series being saturated hydro- 
 carbons, are practically indifferent to chemical reagents. 
 Common paraffin consists of several of them, and the 
 series has therefore been called the "paraffin series" ; those 
 of the second series; because their compounds are on the 
 type of the alkali-metals, are termed "alky Is"; the mem- 
 bers of the third series have been called olefins, from the 
 older name of one of the members of it. 
 
 PARAFFIN OR METHANE SERIES. 
 
 The members of this series are saturated molecules not 
 easily affected by chemical agents. Many of them are 
 found in petroleum. 
 
 Methane, Marsh Gas, CH 4 . This is a colorless and odor- 
 less gas which is formed at the bottom of marshes and 
 stagnant pools (whence the name marsh gas) as the result 
 of the slow hydrolysis of cellulose. 
 
 C 6 H 10 5 + H 2 = 3 CH 4 + 3 C0 2 
 
 This decomposition is probably due to the presence of 
 microorganisms. The gas may be collected by filling a 
 bottle completely with water, inserting a funnel, and stir- 
 ring the decaying vegetable matter in the bottom of the 
 pool while holding the bottle and funnel in an inverted 
 position under the surface of the water. The bubbles 
 which arise may be guided through the funnel into the 
 bottle in order to displace the water. 
 
 Methane is a product of ordinary putrefaction and 
 also results from the slow decomposition of certain varie- 
 
52 ORGANIC CHEMISTRY. 
 
 ties of coal. When mixed with air it constitutes -firedamp 
 that causes explosions in coal mines. Coal-gas manu- 
 factured for illuminating purposes consists of nearly 50 
 per cent, of methane; the natural gas, largely used for 
 fuel and illuminating purposes in some parts of the United 
 States, is almost pure methane (about 90 per cent.). Me- 
 thane may be produced artificially in several ways: the 
 most convenient method for experimental purposes is to 
 strongly heat a mixture of anhydrous Sodium acetate, so- 
 dium hydroxide and calcium oxide. 
 
 Experiment i. Mix intimately, by rubbing in a mortar, equal 
 parts of dried sodium acetate and quicklime. Introduce the 
 mixture into an ignition tube and apply strong heat. Methane 
 will be evolved and may be ignited at the mouth of the tube. A 
 portion of the gas may be collected over water and its explosive 
 qualities tested after mixing it with air. 
 
 Ethane, C 2 H 6 , is a colorless and odorless gas, found in 
 natural gas in small amounts and also existing in crude 
 petroleum. 
 
 Propane, C 3 H 8 ; Butane, C 4 H 10 ; Pentane, C 5 H 12 ; Hex- 
 ane, C 6 H 14 and Heptane, C 7 H 16 , are all found in crude 
 petroleum. 
 
 Butane is more commonly known as ' * Cymogene ' ' and is 
 used as an anesthetic in surgery. 
 
 Pentane, commonly called "Rhigolene" is used as an 
 anesthetic and solvent. The vapor of pentane is used as a 
 standard in determining the illuminating power of gas 
 and electric lamps. 
 
 Hexane, commonly known as '"Gasolene," is used as a 
 solvent and for illuminating and heating purposes. 
 
 The hydrocarbons or petroleum products boiling between 
 70 and 120 and having a specific gravity between 
 0.685 an d 0.690 are known under the name of "Ligroin." 
 
PARAFFIN OR METHANE SERIES. 53 
 
 The use of the terms benzine, benzin and benzolene has 
 led to great confusion between the petroleum products and 
 benzene, C 6 H 6 , (benzol), the principal constituent of coal- 
 tar naphtha. 
 
 Heptane exists in petroleum spirit and also constitutes 
 the greater portion of the oil from Pinus Sabiniana. It is 
 used as a solvent under the trade designation of "Abietene." 
 
 Kerosene, or Coal Oil, is that mixture of the hydro- 
 carbons which is most suitable for burning in lamps. The 
 name kerosene is a contraction of keroselain or ''wax 
 oil" and was originally a trade-mark for a certain fraction 
 of petroleum oil. 
 
 The hydrocarbons from C 16 H 34 to C 20 H 42 constitute the 
 various grades of petrolatum. Some members of the olefin 
 series are also associated with the paraffins in these 
 compounds. The different consistencies, colors and melt- 
 ing-points of petrolatum preparations are obtained by 
 different methods and represent varying degrees of puri- 
 fication. Commercial products not differing materially 
 from petrolatum are sold under various trade names, as 
 cosmoline, vaseline. 
 
 A mixture of hydrocarbons having a higher melting point 
 than the petrolatums constitutes the product known as 
 paraffin. The name paraffin, from parum, without, 
 affinis, affinity, has also been applied to the entire group 
 of saturated hydrocarbons, indicating the difficulty of 
 inducing chemical change. Common paraffin is a white, 
 waxy solid, having a melting point of from 45 to 65 
 and a metallic sound when struck. It has an extensive use 
 as a substitute and adulterant for beeswax and spermaceti. 
 
 A small amount of these hydrocarbons is sufficient to form ex- 
 plosive mixtures with a large volume of air. This may be illus- 
 trated by pouring a few drops of one of the volatile products into 
 
54 ORGANIC CHEMISTRY. 
 
 a i oo c.c. beaker, covering it with a glass plate, and, after a few 
 minutes, removing the plate and applying a light. 
 
 Synopsis of the Paraffin Series. The lowest members of 
 the series at ordinary temperatures are gaseous, the inter- 
 mediate members liquid and the higher members solid. 
 The boiling points rise with the molecular weights and in 
 the higher members of the series the specific gravities and 
 melting points show a regular increase. The following 
 tables illustrate these facts : 
 
 C 3 H 8 Propane 
 C 4 Hi Normal Butane 
 
 Trimethyl Methane 
 C5H 12 Normal Pentane 
 
 Dimethylethyl Methane 
 
 Tetramethyl Methane 
 C 6 H 14 Normal Hexane 
 
 Methyldiethyl Methane 
 
 Dimethylpropyl Methane 
 
 Di-isopropyl 
 
 Trimethylethyl Methane 
 
 Structural Formula. 
 CH 3 .CH 2 .CH 3 
 CH 3 .CH 2 .CH 2 .CH 3 
 CH 3 .CH(CH 3 ) 2 
 CH 3 .(CH 2 ) 3 .CH 3 
 CH 3 .CH 2 .CH(CH 3 ) 2 
 C(CH 3 ) 4 
 CH 3 (CH 2 ) 4 CH 3 
 CH 3 (C 2 H 5 ) 2 CH 
 CH 3 .CH 2 .CH 2 .CH(CH 3 ) 2 
 (CH 3 ) 2 .CH.CH.(CH 3 ) 2 
 CH 3 .CH 2 .C(CH 3 ) 3 
 
 Melting Point. B. P. 
 
 Heptane C 7 H 16 ... 98.4 
 
 Octane C 8 H 18 ... 125.5 
 
 Nonane C 9 H 20 51 I 49-5 
 
 Decane C 10 H 22 -32 g 173 
 
 Undecane C U H 24 26.5 g 194.5 
 
 Dodecane C 12 H 26 12 214 
 
 Tridecane C 13 H 28 - 6.2 * 234 
 
 Tetradecane C 14 H 30 +5-5 1252.5 
 
 Pentadecane C 15 H 32 + 10 *r 270.5 
 
 Hexadecane C 16 H 34 + 18" fc 287.5 
 
 Heptadecane C 17 H 36 +22.5 fc 303 
 
 Octadecane C 18 H 38 +28 1 317 
 
 Nonadecane C 18 H 40 + 32 P 330 
 
 Eicosane C 20 H 42 + 36.7 205 
 
 Heneicosane . . . .C 21 H 44 +40.4 | 215 
 
 Docosane C 22 H 46 +44.4 224.5 
 
 Tricosane C 23 H 48 + 47-7 * 2 34 
 
 Tetracosane C 24 H 50 +51.1 | 243 
 
 Heptacosane . . . .C 27 H 58 +59-5 2> 2 7 
 
 Hentriacontane . .C 31 H 64 + 68.1 302 
 
 Dotriacontane . . .C 32 H 66 +70.0 % 310 
 
 Pentatriacontane.C 35 H 72 +74.7 5 I 33 l0 
 
 Dimyricyl Q 60 H 122 + 102 
 
 Boiling point below 
 
 760 mm. 
 
 -45 (B. 27, 3306) 
 + i (B. 27, 2768) 
 -17 
 +38 
 +30 
 -fio 
 +71 
 +64 
 +62 
 +58 
 +430-48 
 
 Sp. Gr. 
 0.7006(0) 
 0.7188(0) 
 
 0.7330(0) 
 0.7456(0) 
 
 0-773 
 0-775 
 0-775 
 o-775 
 0-775 
 0.776 
 0.776 
 o.777 
 0-777 
 0.778 
 0.778 
 0.778 
 0.778 
 
 0-779 
 0.780 
 0.781 
 0.781 
 
 At their 
 M. P. 
 
PARAFFIN OR METHANE SERIES. 55 
 
 DERIVATIVES OF THE PARAFFINS. Paraffins are not 
 easily acted upon by chemical agents. Substitution com- 
 pounds may be obtained by direct action of chlorine and 
 bromine upon all of them, and nitro-compounds may also 
 be produced directly from some of the higher members. 
 
 By successive substitution of the hydrogen in CH 4 four 
 derivatives are obtained which will serve as an illustration 
 of the nomenclature of this class of compounds. 
 
 Methane CH 4 
 
 Monochlormethane (methyl chloride) CH 3 C1 
 
 Dichlormethane (methene chloride) CH 2 C1 2 
 
 Trichlormethane (methenyl chloride) CHC1 3 
 
 Tetrachlormethane (carbon tetrachloride) - . . CC1 4 
 
 The first substitution product, monochlormethane or 
 methyl chloride, CH 3 C1, may be made by the direct action 
 of chlorine on methane or by the action of hydrochloric 
 acid gas on methyl hydroxide. It is gaseous at ordinary 
 temperatures but is liquefied under a pressure of several 
 atmospheres. This liquid is sometimes used to produce 
 local anesthesia. 
 
 The second product, dichlormethane or methylene chloride, 
 CH 2 C1 2 , may be prepared by the action of chlorine upon 
 methane or upon methyl chloride. It is a colorless liquid 
 boiling at 41 and has been used as an anesthetic. 
 
 The third substitution, trie hlor methane , is the important 
 body, chloroform, CHC1 3 . It may be made by the direct 
 action of chlorine upon methane but it is usually made by 
 the action of chlorinated lime upon alcohol or acetone. 
 
 When pure it is a colorless, fragrant, mobile, volatile 
 liquid, sp. gr. 1.49, boiling point 60, sparingly soluble in 
 water, soluble in all proportions in alcohol, ether, petro- 
 leum spirit and fixed and volatile oils. It is not readily in- 
 flammable, but vapor from boiling chloroform burns with a 
 
56 ORGANIC CHEMISTRY. 
 
 greenish flame. It is used in analytical chemistry as a 
 solvent. It has marked antiseptic powers. When in- 
 haled it produces deep anesthesia ; when swallowed it acts as 
 an irritant. Pure chloroform is unstable; the commercial 
 article contains about i per cent, of alcohol which acts 
 as a preservative. 
 
 Experiment 2. Mix 100 grams of chlorinated lime with about 
 500 c.c. of water in a large flask provided with a thistle tube and 
 a distillation tube which is connected with a well-cooled condenser. 
 Add gradually, through the thistle tube, about 30 c.c. of acetone 
 and apply a gentle heat until the chloroform begins to distil over, 
 when the heat may be regulated according to the rapidity of the 
 distillation. Purify the chloroform by first washing it with water, 
 then with a small quantity of sulphuric acid, and finally with a 
 solution of sodium carbonate, after which it may be distilled on 
 the water bath. 
 
 Instead of the thistle tube and delivery tube, the arrangement 
 shown in Fig. 57 may be used. The acetone is placed in the stop- 
 pered funnel tube and the addition of it is easily controlled. The 
 hemispherical dish (the bowl of an ordinary water-bath) contains 
 water heated gently by the burner. The bowl is moved up so as 
 to include the lower half of the flask. Cold water passes through 
 the condenser. This arrangement of apparatus is suitable for 
 many distillations. 
 
 Carbon tetrachloride , CC1 4 , is the final result of the 
 successive substitution of the hydrogen of methane by 
 chlorine. It is a colorless liquid having an odor resembling 
 chloroform; sp. gr. 1.56. It boils at 68. It is a power- 
 ful anesthetic but is most largely used at the present 
 time as a non-inflammable solvent in manufacturing 
 and technical operations. 
 
 Bromofonn, CHBr 3 , is analogous in composition to 
 chloroform and is used mainly as an anesthetic. 
 
 lodoform, CHI 3 , is also analogous to chloroform, and 
 
PARAFFIN OR METHANE SERIES. 57 
 
 is largely used as an antiseptic in surgery. It cannot 
 be obtained by direct substitution of iodine in the methane 
 
 FIG. 9. 
 
 group, but it is made by the action of iodine on alcohol or 
 acetone in the presence of an alkali. It has a pene-' 
 trating, disagreeable odor. It crystallises in bright yel- 
 
58 ORGANIC CHEMISTRY. 
 
 low hexagons which are soluble in chloroform, ether and 
 petroleum spirit. 
 
 Experiment 3. Dilute 2 c.c. of acetone to make about 10 c.c., 
 and add a solution of i gram of potassium iodide and i gram of 
 sodium hydroxide dissolved in about 5 c.c. of water; then add 
 solution of sodium hypochlorite drop by drop, observing the 
 separation of yellow crystals of iodoform, which may be collected 
 on a filter paper, dried and tested for solubility in water, alcohol 
 and ether. 
 
 ALKYLS, MONATOMIC ALCOHOL RADICLE SERIES. This 
 is a series of monad radicles sometimes called the methyl 
 series, often the alcohol radicles, because their hydroxides 
 are the common alcohols. The term alkyls is most con- 
 venient. The following derivatives are obtained from this 
 series : 
 
 Normal oxides called ETHERS : 
 
 (CH 3 ) 2 O, methyl ether, analogous to Na 2 O, sodium oxide. 
 (C 2 H 5 ) 2 O, ethyl ether, analogous to Na 2 O, sodium oxide. 
 
 Compounds with halogens, also sometimes called ETHERS : 
 
 CH 3 C1, methyl chloride, analogous to NaCl, sodium chloride. 
 C 5 H n Cl, amyl chloride, analogous to NaCl, sodium chloride. 
 
 Compounds derived from acids called ESTERS or COM- 
 POUND ETHERS: 
 
 C 2 H 5 NO 2 , ethyl nitrite, analogous to NaNO 2) sodium nitrite. 
 CsHnCgHgOa, amyl acetate, analogous to NaC 2 H 3 O 2 , sodium 
 acetate. 
 
 The compounds analogous to the acid salts are some- 
 times called VINIC ACIDS: 
 
 C 2 H 5 HSO 4 , sulphethylic or sulphovinic or ethylsulphuric acid, 
 analogous to KHSO 4 . 
 
PARAFFIN OR METHANE SERIES. 59 
 
 Hydroxides called ALCOHOLS: 
 
 CH 3 OH, methyl alcohol, analogous to KOH, potassium hydroxide 
 C 2 H 6 OH, ethyl alcohol. 
 CgHnOH, amyl alcohol. 
 
 Compounds containing two different radicles are called 
 MIXED ETHERS: 
 (CH 3 )(C 2 H 5 )O, methylethyl ether. 
 
 Each compound here mentioned is a member of a homol- 
 ogous series. 
 
 In general, when alcohols are oxidised by a limited 
 amount of oxygen, two atoms of hydrogen are removed 
 and no oxygen is added. When oxidised in a free supply 
 of oxygen, an atom of oxygen takes the place of the 
 removed hydrogen. In this way is obtained: 
 
 Ethyl alcohol Ethyl aldehyde. 
 
 C 2 H 5 OH + O = C 2 H 4 O + H 2 O 
 
 Acetic acid. 
 
 C 2 H 5 OH + 2 = C 2 H 4 2 + H 2 
 
 Thus each alcohol or hydroxide may be made to yield 
 an aldehyde (from alcohol dehydrogenatum) and an acid, 
 each of these being one of a homologous series. 
 
 The series of acids is very important; many of them 
 are obtained from fats and oils, hence have been called 
 fatty-acids. The following table gives an outline of 
 some of the important derivatives of this series. One 
 atom of the hydrogen in the acid is replaceable by any 
 positive element or radicle, so that it is generally written 
 apart from the other atoms as in HC 2 H 3 O 2 , acetic acid. 
 In this table only a few of the esters are given. 
 
 Isomeric modifications are possible in these bodies, 
 except with methyl, ethyl and some of their derivatives. 
 

 
 CD* 
 
 
 
 
 0) 
 
 
 
 
 
 
 M 
 
 
 
 CD 
 
 o" 
 
 CD 
 
 
 
 4-> 
 OJ 
 
 eo 
 
 CD 
 4J 
 
 Oj 
 
 cf 
 
 CD 
 
 4^ 
 
 'jH 
 
 4\j 
 
 s 
 
 
 
 O 
 gg 
 
 ^ 
 
 'S 
 
 x ^ 
 
 *2 
 
 ^ 
 
 .15 
 
 ^ 
 
 
 fc 
 
 w 
 
 o 
 
 
 *>* 
 
 ffi 
 
 ^ 
 
 a| 
 
 js 
 
 sf 
 
 ^ 
 
 5? 
 
 5 
 
 
 
 ^ 
 
 cj 9 
 
 4-3 
 
 c? 
 
 a 
 
 c? 
 
 -g 
 
 d 5 
 
 | 
 
 
 
 
 1 
 
 
 
 
 2 
 
 
 PQ 
 
 
 
 ACIDS. 
 
 HCOOH 
 
 jd 
 1 
 
 CJ 
 
 s 
 
 
 
 HH 
 
 M 
 
 
 
 
 O M 
 M 
 
 
 
 .12 
 
 0) 
 
 
 
 M 
 
 
 
 o 
 
 K 
 O M 
 
 ropionic acid. 
 
 K 
 
 
 
 ^d 
 1 
 
 W 
 ffl 
 
 3 
 
 
 
 
 
 
 
 PM 
 
 
 
 
 
 
 
 CD . 
 
 
 
 
 CD* 
 
 
 
 
 
 
 
 
 
 CD ^- 
 
 
 
 
 CD* 
 
 
 
 
 
 
 
 TT-J CD 
 
 
 
 
 
 
 
 
 
 
 _fi 1>^ 
 
 
 ^gl 
 
 
 _ri^ 
 
 
 K^> 
 
 
 >% 
 
 8 
 
 Q 
 > 
 
 Q 
 
 *& CD 
 
 q, 
 
 ^^ 
 
 
 
 ^d 
 
 q 
 
 T3 
 
 
 
 
 
 1 
 
 S 
 
 w 
 
 HH 
 
 13 2 
 
 HH 
 
 13 2 
 
 ffi 
 
 13 
 
 HH 
 
 
 K 
 
 i 
 
 Q 
 
 O 
 
 *>> S 
 
 b 
 
 ^H 4J 
 
 cJ 
 
 * 
 
 o* 
 
 r _, 
 
 O 
 
 
 < 
 
 
 O 
 
 
 >^ CD 
 
 r^H 
 
 
 PH 
 
 o 
 
 
 4^ 
 
 
 s 
 
 
 
 l fe 
 
 
 "^ "^ 
 
 rVI 
 
 
 ^H 
 
 PH 
 
 
 PQ 
 
 
 < 
 
 8 
 
 < 
 
 
 
 "o 
 
 o 
 o 
 
 
 
 13 
 
 ^ 
 
 
 
 
 
 'o 
 
 "3 
 
 
 
 'o 
 
 
 
 
 
 1 
 
 
 
 t/Tyj 
 
 W j 
 
 
 13 
 
 ffl 
 
 
 &3 
 
 13 
 
 H^ 
 
 
 ^t 
 
 rS 
 
 So 
 
 X K 
 
 CO 
 
 HH 1 
 
 !> 
 
 ffi 5 
 
 2 
 
 K I 
 
 ^ 
 
 K 
 
 Jj 
 
 ffi" 
 
 ^ 
 
 
 
 
 
 
 
 c_T 
 
 >^ 
 
 cT 
 
 PH 
 
 c5" 
 
 >^> 
 
 cf 
 
 g 
 
 Q 
 
 
 4-> 
 
 
 rC 
 
 
 
 
 
 *5 
 
 
 H 
 
 J>4 
 
 
 
 
 
 
 ;_, 
 
 
 
 
 
 E 
 
 
 S 
 
 
 w 
 
 
 PH 
 
 
 PQ 
 
 
 J 
 
 W) 
 
 M 
 
 H 
 
 I 
 
 
 
 CD 
 
 
 
 1 
 
 
 
 CD 
 
 O M 
 
 IH 
 
 CD 
 ^ 
 
 0^ 
 
 ^H* 
 
 CD 
 
 h 
 Ed 
 
 ^s 
 
 CD 
 
 ^ 
 
 4^> 
 CD 
 
 ^ 
 
 CD 
 
 '"S 
 
 4J 
 
 CD 
 
 '"^ 
 
 "S 
 
 OXIDES, : 
 
 s 
 
 "CD 
 
 i 
 
 !* 
 
 3 
 
 1 
 
 & 
 
 
 
 4-> 
 ^ 
 
 PQ 
 
 ffi 
 
 ^ 
 S 
 
 in 
 
 
 , * 
 
 
 
 
 ^ 
 
 
 
 
 
 H 
 
 
 
 
 
 !>. 
 
 >^ 
 
 
 
 
 
 J 
 O 
 
 HH 
 
 rb 
 
 
 
 ,d 
 
 K M 
 
 
 HH 
 
 4^ 
 
 HH 
 
 &' 
 
 S 
 
 < 
 
 K 
 
 
 
 1 
 
 
 
 
 d 
 
 S 
 
 PM 
 
 o" 
 
 PQ 
 
 d 5 
 
 < 
 
 60 
 
PARAFFIN OR METHANE SERIES. 
 
 61 
 
 Methods of Forming the Compounds of the Methyl Series. 
 
 The starting point is generally the alcohols. The ethers, 
 simple and compound, are produced by the action of acids 
 on the alcohols. The aldehydes are produced by partial 
 oxidation, the acids by complete oxidation; many of the 
 acids exist ready formed in nature. 
 
 The alcohols will be described first. They are often 
 called the monatomic alcohols, because they contain a 
 monatomic (i. e., monad) radicle. 
 
 CONSPECTUS OF MONATOMIC ALCOHOLS. 
 
 FORMULA. 
 
 SYSTEMATIC 
 NAME. 
 
 COMMON NAME. 
 
 SOURCE. 
 
 CH 3 OH 
 
 Methyl 
 
 Wood spirit 
 
 Distillation of wood. 
 
 C 2 H 5 OH 
 
 Ethyl 
 
 Alcohol 
 
 Fermentation. 
 
 C 3 H 7 OH 
 
 Propyl 
 
 Propyl alcohol 
 
 M 
 
 C 4 H 9 OH 
 
 Butyl 
 
 Butyl 
 
 M 
 
 C 6 H U OH 
 
 Pentyl 
 
 Amyl 
 
 11 
 
 
 
 Fusel oil 
 
 
 C 6 H 13 OH 
 
 Hexyl 
 
 Caproic alcohol 
 
 
 C 7 H 15 OH 
 
 Heptyl 
 
 ^Enanthic " 
 
 Action of KHO on 
 
 
 
 
 castor oil. 
 
 C 8 H 17 OH 
 
 Octyl 
 
 
 From parsnip oil. 
 
 C 9 H 19 OH 
 
 Nonyl 
 
 
 
 C 10 H 21 OH 
 
 
 
 
 C 12 H 25 OH 
 
 
 
 
 C 14 H 29 OH 
 
 
 
 
 C 16 H 33 OH 
 
 Hexadecyl 
 
 Cetyl 
 
 Spermaceti. 
 
 C 18 H 37 OH 
 
 
 
 
 CsoHaiOH 
 
 
 Triakontyl (my- 
 
 
 
 
 ricyl alcohol) 
 
 Beeswax. 
 
 Methyl alcohol, (CH 3 )HO, wood spirit, is usually made 
 by distilling wood. The crude material is purified to 
 such an extent that it has very little odor and closely 
 resembles ethyl alcohol in its physical properties. Pure 
 methyl alcohol is a colorless, inflammable liquid of pleasant 
 
62 ORGANIC CHEMISTRY. 
 
 odor and soluble in water, ethyl alcohol, ether and 
 glycerol. It boils at 66.5. The effects on the animal 
 system are so dangerous as to even prohibit its use in 
 small proportions in making preparations intended for in- 
 ternal administration; the most prominent effect follow- 
 ing its use is blindness, due to atrophy of the optic nerve. 
 Methylated spirit, a mixture of 90 parts common alco- 
 hol with 10 parts of crude methyl alcohol, was formerly 
 largely used in Great Britain as a tax-free substitute for 
 ordinary alcohol, the presence of the methyl alcohol render- 
 ing it. unfit for use in any preparations to be given inter- 
 nally. 
 
 H O 
 
 II 
 H D C H H C H 
 
 A 
 
 Hydroxymethane Methyl aldehyde 
 
 (Methyl alcohol, carbinol) (Formaldehyde) 
 
 The presence of methyl alcohol in ethyl alcohol may be deter- 
 mined as follows: The suspected sample (which may be first 
 fractionally distilled) is diluted with water to reduce the strength 
 to about 10 per cent. A copper spiral, made by winding copper 
 wire closely around a lead pencil or similar cylindrical body, for 
 a distance of about 5 c.c., is heated to redness and plunged into 
 the diluted alcohol; this operation is repeated five or six times, 
 after which the liquid is gently boiled for a few minutes and filtered 
 if necessary. The effect of the heated copper spiral is to reduce 
 both the ethyl and methyl alcohols to the corresponding aldehydes. 
 The ethyl aldehyde being more volatile is removed by boiling 
 after which the remaining liquid may be tested for the presence 
 of formaldehyde by any of the standard methods. This process 
 will detect as small a quantity as 2 per cent, of methyl alcohol in 
 ethyl alcohol. 
 
PARAFFIN OR METHANE SERIES. 63 
 
 Ethyl alcohol, (C 2 H 5 )HO, common alcohol, grain alcohol, 
 spirit of wine, is produced in the vinous fermentation of 
 sugar, carbon dioxide being the only other product formed 
 in large amount; it can also be prepared synthetically. 
 The fermented spirit is concentrated by distillation in a 
 rectifying still and column, but the strongest thus pre- 
 pared contains about 5 per cent, of water and constitutes 
 the ordinary alcohol of commerce. To withdraw all water 
 it is necessary to distil with quicklime, anhydrous copper 
 sulphate or calcium chloride, by which absolute alcohol is 
 formed. 
 
 Alcohol is a colorless, transparent, inflammable liquid, 
 of a faint but characteristic odor and a sharp burning 
 taste, sp. gr. about 0.825, boiling point 78. It is soluble 
 in all proportions in water, ether and glycerol and is 
 largely used as a solvent. Absolute alcohol is a slightly 
 better solvent than ordinary alcohol for some volatile oils 
 and resins. It attracts moisture so readily from the air 
 that it is difficult to preserve it in the absolute condition. 
 
 Proof -spirit contains, by weight, 50.8 parts of absolute 
 alcohol to 49.2 of water and has a sp. gr. of 0.920. Alcohol 
 is contained in wine, beer and spirits. Whisky, brandy 
 and other spirits contain from 40 to 50 per cent, of alcohol; 
 wines, from 17 (port and madeira) to 7 or 8 (hock and light 
 clarets) per cent. ; porter and strong ale contain from 6 to 8 
 per cent., lager beer about 3.5 per cent.; the mild fer- 
 mented liquors known as mead, root-beer, spruce-beer, 
 contain from i to i per cent. The effervescence of fer- 
 mented liquids is due to the carbon dioxide which is 
 produced with alcohol: 
 
 Alcohol. 
 ' C 6 H 12 O 6 breaks up into 2C 2 H 6 O + 2CO 2 
 
64 ORGANIC CHEMISTRY. 
 
 The carbon dioxide in sparkling alcoholic beverages, is 
 retained by bottling the liquid before the fermentation 
 is over. 
 
 In the production of alcohol by fermentation other 
 substances are formed, some of which contaminate the 
 product even after repeated distillation. One of these, 
 known as fusel oil, consists of a mixture of several of the 
 higher members of the same homologous series. The 
 presence of this impurity is usually determined by the 
 characteristic odor which is left on filter paper after a small 
 quantity of the alcohol has been allowed to evaporate 
 from it. Aldehyde, which is an oxidation product of 
 alcohol; is sometimes present and may be detected by the 
 brown color which it produces with a solution of potassium 
 hydroxide. 
 
 Experiment 4. Place about 5 c.c. of absolute alcohol in one 
 testtube and about 5 c.c. of ordinary alcohol in another testtube. 
 Add about 0.5 gram of anhydrous copper sulphate to each and 
 note the difference in the effect. 
 
 Experiment 5. Dissolve about 100 grams of cane sugar in 1000 
 c.c. of water and place the solution in a large bottle or wide- 
 mouthed jar. Add to this solution about one-fourth of a cake of 
 compressed yeast and stand the mixture aside for fermentation to 
 take place. When the fermentation is complete, which may be 
 known by no more bubbles of carbon dioxide being given off, 
 transfer the solution to a large distilling flask and collect about 
 100 c.c. of the first distillate which comes over. Test this distillate 
 for alcohol by means of the iodoform reaction. 
 
 Sodium etkylate is obtained by the action of sodium upon 
 alcohol. The substitution takes place rapidly, hydrogen 
 being evolved, but only the hydroxyl group is attacked. 
 The resulting compound is a solid, very soluble in water 
 and alcohol, and corrosive. It saponifies fats *nore rap- 
 idly than an aqueous solution of sodium hydroxide. 
 
PARAFFIN OR METHANE SERIES. 65 
 
 H H 
 
 H C C O Na 
 H H 
 
 Sodium ethylate 
 (Sodium ethoxide) 
 
 Amyl alcohol, Pentyl alcohol, C 5 H n HO. Eight isomers, 
 four primary, three secondary and one tertiary (see be- 
 low) are possible; all have been obtained. Several have 
 asymmetric carbon. Some of the amyl alcohols are by- 
 products in vinous fermentations and hence are found in 
 alcoholic beverages. They are especially noticeable in the 
 fermented liquor from potato starch (hence the name 
 "amyl" alcohol, from a Greek word for starch). These 
 alcohols may be separated in part by distillation. The 
 mixture of them thus obtained is known commercially as 
 "fusel oil." It is supposed to be very poisonous and to 
 give very injurious properties to liquors containing even 
 small amounts, but these points are not established. The 
 pure amyl alcohols are colorless liquids, nearly insoluble 
 in water and of a hot, acrid taste. 
 
 The higher alcohols are mostly oily liquids or wax-like 
 solids. 
 
 Isomeric Forms of Alcohols. Methyl and ethyl alcohols 
 present only one form, but a number of isomers of the 
 higher alcohols have been obtained. Comparison of these 
 isomers has led to their division, according to an assumed 
 arrangement of the carbon atoms, into three groups, 
 primary, secondary and tertiary alcohols. 
 5 
 
66 ORGANIC CHEMISTRY. 
 
 Primary alcohols contain the group CH 2 OH joined to 
 one alcohol radicle; secondary alcohols contain the group 
 CHOH joined to two radicles; and tertiary alcohol con- 
 tains the group COH, joined to three radicles. 
 
 Illustrations of these principles are found in the struc- 
 tural formulas of the three butyl (tetryl) alcohols. The 
 secondary form contains asymmetric carbon indicated by 
 italic symbol: 
 
 H H H H H H H 
 
 H-O C C C C-H H-O C C C-H 
 
 H H H H H C H H 
 
 H A H 
 
 Primary butyl alcohol Secondary butyl alcohol 
 
 H 
 
 H C H 
 
 I H 
 
 H O C C< 
 
 I i H 
 H C H 
 
 H A H 
 
 Tertiary butyl alcohol 
 
 ETHERS. 
 
 The primary alcohols, by the action of bodies which have 
 an affinity for water (sulphuric and phosphoric acids), 
 are converted into oxides, called ethers. A compound 
 
ETHERS. 67 
 
 ether or ester is the replacement of the hydrogen of an acid 
 by one or more molecules of a hydrocarbon. The only 
 simple ether of any importance is: 
 
 Ethyl oxide, (C 2 H 5 ) 2 O, ether, often wrongly called sul- 
 phuric ether, made by the action of sulphuric acid upon 
 alcohol. Acid ethylsulphate is first formed and then 
 decomposed : 
 
 Alcohol. Acid ethylsulphate.- 
 
 (C 2 H 5 )HO + H 2 S0 4 == (C 2 H 5 )HS0 4 + H 2 O 
 Another molecule of alcohol is then acted upon, thus: 
 
 Ether. 
 
 (C 2 H 5 )HO + (C 2 H 5 )HS0 4 = H 2 S0 4 + (C 2 H 5 ) 2 O 
 
 It will be seen from these reactions that in theory the 
 sulphuric acid is continuously re-generated. This is not 
 true in practice on account of reactions between the sul- 
 phuric acid and the impurities in the alcohol. 
 
 Ether is a colorless mobile, very volatile liquid, of 
 a characteristic odor, boiling at 37. Sp. gr. 0.723. Its 
 vapor is inflammable and very heavy. It is insoluble 
 in water, soluble in alcohol and is a solvent for fats, fixed 
 and volatile oils, resins and many other proximate prin- 
 ciples. Its vapor is anesthetic. 
 
 Experiment 6. Warm a beaker of about 250 c.c. capacity 
 slightly in the flame of a bunsen burner; pour into it a few c.c. of 
 ether and cover the beaker with a watch glass for a few moments. 
 Take another beaker of the same size and, having removed the 
 watch glass, invert the beaker containing the ether vapor over the 
 empty beaker, with a motion similar to that used in pouring 
 liquids from one vessel to another. Test the vapor in the second 
 beaker for inflammability, using a lighted taper. This shows that 
 the vapor of ether is considerably heavier than atmospheric air. 
 
68 ORGANIC CHEMISTRY. 
 
 The molecular structure of simple and mixed ethers is 
 illustrated by the annexed formulas: 
 
 H H H H H H H 
 
 H C C O C C-H H-C C O C H 
 
 H H II H H H H 
 
 Ethyl ether. Methylethyl ether. 
 
 Heavy oil of wine is a by-product in the manufacture of 
 ether and consists of a mixture of sulphuric esters of the 
 hydrocarbons. When mixed with an equal volume of 
 ether it constitutes ethereal oil which is one of the con- 
 stituents of the official compound spirit of ether (Spiritus 
 (Biker is compositus), commonly known as Hoffman's anodyne. 
 
 Esters, Compound Ethers. Many of these have char- 
 acteristic odors and are the flavoring materials of flowers 
 and fruits. They can be made synthetically. 
 
 The usual method of preparation is to heat a mixture of 
 the sodium salt of the proper acid, the alcohol containing 
 the proper radicle and sulphuric acid. Thus to produce 
 ethyl acetate, sodium acetate, ethyl alcohol and sulphuric 
 acid are used: 
 
 C 2 H 5 HO + NaC 2 H 3 2 + H 2 SO 4 = C 2 H 5 C 2 H 3 O 2 + NaHSO 4 + H 2 O 
 
 Mixtures of esters are used as imitation flavors. The 
 following are the more important: 
 
 Methyl acetate, CH 3 C 2 H 3 O 2 , is a colorless liquid used as a 
 solvent. In association with acetone, it dissolves pyr- 
 oxylin. 
 
 Methyl salicylate C 6 H 4 OHCOOCH 3 constitutes the 
 greater portion of oil of wintergreen and oil of birch. 
 
ETHERS. 69 
 
 Ethyl acetate, C 2 H 5 C 2 H 3 O 2 , is a colorless liquid of a 
 characteristic agreeable fruity odor. It is largely used in 
 compounding fruit essences. 
 
 Ethyl butyrate, C 2 H 5 C 4 H 7 O 2 , is also largely used in 
 artificial flavoring extracts. 
 
 Ethyl bromide, C 2 H 5 Br, is an anesthetic. 
 
 Ethyl nitrite, C 2 H 5 NO 2 , is the active ingredient of the 
 official spirit of nitrous ether, commonly known as sweet 
 spirit of nitre. (Spiritus cetheris nitrosi.) 
 
 Amyl nitrite, C 5 H 11 NO 2 , is made by the action of nitric 
 acid upon amyl alcohol. It is a yellowish liquid, of well- 
 marked odor, boiling at 96. It is used in medicine by 
 inhalation, for the relief of angina pectoris. 
 
 Amyl acetate, C 5 H n C 2 H 3 O 2 , is another of the esters 
 largely used in compounding artificial fruit flavors. It is 
 also used as a solvent, especially in preparing the lac- 
 quering solutions and the so-called pyroxylin varnishes. 
 
 Experiment 7. In a tubulated retort place 5 grams of red 
 phosphorus and 25 c.c. of absolute alcohol. Connect the retort 
 with a well-cooled condenser, and insert a* separatory funnel pro- 
 vided with a glass stop-cock through the tubulure of the retort, 
 making a tight joint by means of a rubber stopper. Place 25 
 grams of bromine in the separatory funnel, and, having ascertained 
 that all the connections are perfect, allow the bromine to flow into 
 the mixture of red phosphorus and alcohol drop by drop. After 
 allowing the flask to stand for several hours, apply a gentle heat 
 to the flask and collect the ethyl bromide (bromethane) which 
 distils over. Wash the distillate with water in a separatory 
 funnel ; dry it by adding calcium chloride and allowing it to stand ; 
 then redistil and make notes of the boiling point, odor and specific 
 gravity. 
 
 Experiment 8. Mix equal quantities of alcohol and acetic acid 
 in a testtube, cautiously add a little concentrated sulphuric acid 
 and warm the mixture gently. The fragrant odor of ethyl acetate 
 
70 ORGANIC CHEMISTRY. 
 
 will be observed. This reaction may be used as a test for the 
 presence of either acetic acid or alcohol. 
 
 Experiment 9. Dissolve about one gram of sodium nitrite in 
 2 c.c. of water in a testtube. Add about i c.c. of alcohol and 
 then cautiously pour in a mixture, previously made, of i c.c. of 
 sulphuric acid and 2 c.c. of water. The vapor of ethyl nitrite 
 (C 2 H 5 NO 2 ) is evolved, which may be recognised by the fragrant 
 ethereal odor resembling apples. 
 
 Experiment 10. Cautiously mix equal volumes, 5 c.c., of con- 
 centrated sulphuric acid and alcohol and dilute the mixture with 
 about ten times its bulk of water. Add barium carbonate in 
 small portions until effervescence ceases and the liquid is neutral. 
 Filter and examine the clear nitrate for barium. This is a soluble 
 compound of barium with sulphuric acid, called barium ethyl- 
 sulphate, Ba(C 2 H 5 SO 4 ) 2 . 
 
 Sulphur Alcohols, Mercaptans. The oxygen of organic 
 bodies, as of inorganic bodies, may be replaced by 
 any other element of the oxygen group. Ethyl alcohol, 
 for instance, has a corresponding sulphur compound, 
 C 2 H 5 HS, called mercaptan. This is a condensation of a 
 Latin phrase meaning "to take mercury" on account of 
 its action on that element. The proper name is ethyl 
 hydrosulphide. The mercaptans when oxidised form sul- 
 phonic acids which will be taken up later. Corresponding 
 ethers also are known; thus (C 2 H 5 ) 2 S, ethyl sulphide. 
 These derivatives are mostly strong-smelling and irritating 
 compounds. A few of them exist ready -formed in the 
 secretions of animals and plants. The essential oils of 
 mustard, garlic and horseradish are examples, and are 
 noticed elsewhere. 
 
 When the oxygen of carboxyl is replaced by sulphur 
 the prefix "thio" is generally employed. The following 
 structural formula shows one of the positions of the sulphur 
 atom. These bodies are, as exemplified by those just 
 mentioned, mostly of strong, disagreeable odor. 
 
ETHERS. 71 
 
 H-L 
 
 H O 
 
 II 
 
 C S H 
 
 H 
 
 Thiacetic acid 
 
 When both atoms of oxygen are replaced the prefix 
 "dithio" is used. 
 
 Aldehydes. These compounds are formed by the re- 
 moval of two atoms of hydrogen from the corresponding 
 alcohols, and stand intermediate between the alcohols and 
 the acids. 
 
 Ethyl aldehyde, ethanal, usually called acetic aldehyde, or 
 simply aldehyde, C 2 H 4 O,is often present in liquors, especially 
 in raw forms of commercial spirits, and probably gives to 
 such articles some injurious qualities. It is a colorless, 
 volatile liquid, lighter than water, and boiling at 21, 
 having a powerful affinity for oxygen, and therefore a 
 reducing action. It presents several isomeric modifica- 
 tions, one of which, par aldehyde, a polymeric form, to 
 which the formula C 6 H 12 O 3 has been assigned, has 
 hypnotic properties. All the aldehydes of the series form 
 complicated compounds, as yet of little practical value. 
 
 The structural formula of common aldehyde is: 
 
 H O 
 
 I H 
 H C C H 
 
 H 
 
 It will be noted that no hydroxyl is present, and hence 
 aldehyde has neither acid nor basic properties. 
 
 Chloral. The substitution of three atoms of hydrogen 
 
72 ORGANIC CHEMISTRY. 
 
 in aldehyde, by chlorine, produces a colorless liquid 
 heavier than water (sp. gr. 1.18), and boiling at 94. 
 This is trichloraldehyde, C 2 HC1 3 O, chloral. It combines 
 with one molecule of water to form a crystalline, pungently- 
 smelling solid, soluble in water, which is now used under 
 the name of chloral hydrate. In alkaline solution chloral 
 is decomposed as shown in the following equation: 
 
 Sodium Sodium 
 
 Chloral. Hydroxide. Formate. Chloroform. 
 
 C 2 HC1 3 O + NaHO = NaCHO 2 + CHC1 3 
 
 The so-called chloral hydrate (chloral) is trichlorethene 
 glycol, C 2 HC1 3 (HO) 2 . It is a hypnotic and sedative. 
 It is often used for drugging liquor to assist in the commis- 
 sion of robbery or rape. It is decomposed by alkalies 
 in the same manner as chloral. 
 
 H Cl H Cl 
 
 I I H-0 | | 
 
 O-C C Cl >C C Cl 
 
 H O 
 
 Cl 
 
 Trichloraldehyde (chloral) (So-called) Chloral hydrate 
 
 If a few grams of chloral hydrate in a narrow testtube be covered 
 by strong sulphuric acid, the mixture will soon form in two layers; 
 the upper one is chloral, formed by dehydrolysis. 
 
 Experiment n. Dissolve about i gram of potassium dichro- 
 mate in about 10 c.c. of water and add an equal volume of alcohol. 
 Cautiously add about 3 c.c. of concentrated sulphuric acid, note 
 the change in the appearance of the liquid and observe the odor 
 given off. The odor is that of aldehyde and the green color of 
 the liquid indicates that the potassium dichromate has been 
 reduced to chromic sulphate. 
 
 Experiment 12. Prepare formaldehyde from methyl alcohol, 
 by the process given on page 62, tinder the test for methyl alcohol 
 in ethyl alcohol. 
 
ETHERS. 73 
 
 Experiment 13. Dissolve o.i gram of silver nitrate in distilled 
 water; add solution of sodium hydroxide, drop by drop, until no 
 more precipitate forms, and then add ammonium hydroxide until 
 the solution becomes clear. Clean a testtube thoroughly by wash- 
 ing it with soap, by the aid of the testtube brush or swab, and 
 rinsing well with water. Pour in the prepared silver solution, add 
 a few drops of aldehyde (or paraldehyde) and immerse the tube 
 in boiling water. Silver will be set free by the reducing action of 
 the aldehyde. If the tube is clean, a mirror will be formed on the 
 glass, but otherwise the precipitate will be loose and black. 
 
 Formaldehyde, CH 2 O, has much practical as well as 
 theoretic interest. It is produced by the action of heated 
 copper oxide upon the vapor of methyl alcohol. It is a 
 powerful antiseptic, preserving thoroughly many perish- 
 able articles. The use of formaldehyde in preserving ar- 
 ticles of food and drink is forbidden by law, as it forms 
 insoluble compounds with many proteid substances, and 
 therefore affects the digestibility of the substances thus 
 preserved. It is also a powerful reducing agent. Formal- 
 dehyde is considered by plant physiologists as the starting- 
 point in the formation of the so-called "carbohydrates" of 
 the vegetable kingdom. Its formula multiplied by five 
 gives C 5 H 10 O 5 , pentose, forms of which are common in 
 plants, and by easy changes may produce the sugars and 
 starches. The commercial formaldehyde (formalin) con- 
 sists of a 40 per cent, solution of the gas in water. 
 This solution readily polymerises with the formation 
 of paraformaldehyde, C 3 H 6 O 3 , which upon strongly heat- 
 ing again decomposes into formaldehyde, CH 2 O. 
 
 Ketones. By the destructive distillation of calcium 
 acetate, a body called acetone, C 3 H 6 O, is formed, differing 
 from aldehyde, C 2 H 4 O, by CH 2 . 
 
 (CH 3 COO) 2 Ca = CH 3 COCH 3 + CaCO 
 
74 ORGANIC CHEMISTRY. 
 
 Acetone is the type of a group termed ketones. They con- 
 tain carbonyl, CO, united to two monad radicles. They 
 are reducing agents, form " osazones " (see page 100) and 
 form compounds with sulphites. 
 
 H O H 
 
 I II I 
 H C C C H 
 
 A A 
 
 Acetone 
 (Dimethyl ketone) 
 
 Acetone is produced in the destructive distillation 
 of wood and is used as a solvent in many technical 
 processes. It is a colorless, transparent liquid, of a 
 characteristic, ethereal odor, soluble in all proportions 
 in water, alcohol and ether and resembling the latter 
 liquid in its solvent effect on fats, oils and waxes. It is 
 also used as a solvent for pyroxylin. 
 
 Experiment 14. Prepare a saturated solution of sodium acid 
 sulphite in water, and shake this with an equal volume of acetone. 
 A sulphite compound will be formed and precipitate in the strong 
 solution, but will be dissolved on addition of water. 
 
 FATTY-ACIDS. 
 
 This term, applicable strictly to only a few of the series, 
 is applied to the homologous bodies derived from the 
 alcohols by substitution of two atoms of hydrogen by one 
 atom of oxygen. It is an extensive and important class; 
 nearly all are natural products. The fixed oils and fats 
 yield some of the higher members of the series. Some have 
 
FATTY-ACIDS. 75 
 
 been produced synthetically by a reaction, of which the 
 following is a type: 
 
 Ethyl alcohol. Acetic acid. 
 
 C 2 H 6 + 2 = C 2 H 4 2 + H 2 
 
 Each of the acids so produced contains one carboxyl 
 group, COOH, the hydrogen of which can be replaced by a 
 positive element or radicle, and this fact may be shown 
 by writing each formula with the carboxyl distinguished. 
 The lower members of the series are freely soluble in, 
 and miscible with water, strongly acid and irritating, but 
 as the quantity of carbon and hydrogen increases, the 
 compounds become more and more oily, and the higher 
 members are fatty, feebly acid, insoluble in water, but 
 soluble in alcohol and ether. 
 
 Formic Acid, HCOOH, was originally obtained by 
 distilling the liquid in which the bodies of a species of ant 
 (Lat., formica) had been macerated. It can be prepared 
 in quantity by heating oxalic acid with glycerol. Glycerol- 
 formic ester is produced and then decomposed. The 
 equation shows that hydrolysis and dehydrolysis occur. 
 
 C 3 H 5 (HO) 3 + (COOH) 2 = C 3 H 5 (HO) 2 CH0 2 + CO 2 + H 2 O 
 C 3 H 5 (HO) 2 CHO 2 + H 2 O = HCOOH + C 3 H 5 (HO) 3 
 
 The glycerol being reproduced, a small amount will suffice 
 for the conversion of much oxalic acid. Formic acid is 
 supposed to exist in the secretions of some stinging animals 
 and plants. 
 
 Experiment 15. Place about 10 c.c. of glycerol in a testtube 
 with about 3 grams of oxalic acid and apply heat gradually, by 
 means of a bunsen burner, taking care not to raise the temperature 
 much above the boiling point of water. Test the vapors occa- 
 sionally with moistened blue litmus paper and when acid vapors 
 are evolved, cautiously note the pungent, irritating odor which 
 is due to formic acid. 
 
76 ORGANIC CHEMISTRY. 
 
 Although formic acid has a higher percentage of oxygen 
 than any other member of its series, it has the greatest 
 reducing power. This is mainly because it contains an 
 aldehydic structure, the group HCO, which is not the 
 case with the other normal fatty-acids. The structural 
 formula in comparison with that of acetic acid shows this 
 point : 
 
 O HO 
 
 II I II 
 
 H C O H H C C O H 
 
 H 
 
 Formic acid Acetic acid 
 
 Formic acid is a colorless, highly irritating liquid. 
 
 Acetic Acid, CH 3 COOH. This occurs in small quan- 
 tities in animal and plant juices. In the dilute form it 
 constitutes vinegar, which contains from 3 to 6 per cent, 
 of the acid, and is usually made by oxidising very weak 
 alcohol in the presence of a ferment. Acetic acid is also 
 produced in the distillation of wood. The first distillate is, 
 in this case, generally contaminated with tar and phenol- 
 compounds and is called pyroligneous acid. It is used 
 commercially in preserving meats, and is often sold under 
 the name "Liquid Smoke." Pure acetic acid is a color- 
 less, corrosive liquid, solidifying at 17 (hence often called 
 "glacial acetic acid"), and boiling at 119. The dilute 
 forms are less active, and in vinegar its effects are quite mild. 
 
 ACETATES. The most important of these are: 
 
 Potassium acetate, KC 2 H 3 O 2 , a deliquescent salt, much 
 used in medicine as a diuretic. 
 
 Sodium acetate, NaC 2 H 3 O 2 , which forms efflorescent 
 crystals, containing 3H 2 O. 
 
 Ammonium acetate, (NH 4 )C 2 H 3 O 2 , is used in medicine 
 
FATTY-ACIDS. 77 
 
 in the form of a freshly prepared solution in water, called 
 spirit of Mindererus. (Liquor ammonii acetatis.) 
 
 Lead acetate, Pb(C 2 H 3 O 2 ) 2 , sugar of lead, made by dissolv- 
 ing lead monoxide in acetic acid, forms white crystals, 
 soluble in water. By boiling this solution with lead 
 monoxide, a considerable amount of the latter is dissolved, 
 and the subacetate, more correctly oxyacetate, is formed, 
 called Goulard's extract, in concentrated solution (Liquor 
 plumbi subacetatis) , and when much diluted, Lead water 
 (Liquor plumbi subacetatis dilutus). 
 
 Copper acetate, Cu(C 2 H 3 O 2 ) 2 , is not important; but an 
 irregular and variable compound of it with copper hydrox- 
 ide, known as verdigris, is made by exposing alternate 
 layers of sheet copper and refuse grape skins to the air; 
 ethyl alcohol is formed and then converted into acetic 
 acid which acts on the copper. 
 
 Zinc acetate, Zn(C 2 H 3 2 ) 2 +2H 2 O, is a white efflorescent 
 salt which is used as an astringent. 
 
 A derivative of acetic acid, acetoacetic acid, the 
 structural formula of which is given, is of some theoretic 
 interest. Its ethyl ester, obtained by the action of sodium 
 upon ethyl acetate, the hydrogen of the carboxyl being 
 replaced by ethyl has, contrary to what theory indicates, 
 acid qualities and takes up sodium in exchange for a hy- 
 drogen atom that is in union with carbon. The reason for 
 this unusual action has not been ascertained, but there is 
 probably tautomerism in the formula. 
 
 H O H O 
 
 I II I II 
 H C C C C O H 
 
 Acetoacetic acid 
 
ORGANIC CHEMISTRY. 
 
 Acetic anhydride, (C 2 H 3 O) 2 O, used in some analytic 
 and research operations, is obtained by distilling anhy- 
 drous sodium acetate with phosphoric oxychloride. Struc- 
 turally, it resembles the ethers, but acid radicles, not 
 hydrocarbons, are united by oxygen. 
 
 HO OH 
 
 I II II I 
 
 H C C O C C H 
 
 H 
 
 H 
 
 Acetic anhydride 
 
 HOMOLOGOUS SERIES OF FATTY-ACIDS. 
 
 Common 
 Name. 
 
 Empirical 
 Formula. 
 
 Properties. 
 
 Natural Source. 
 
 Formic 
 
 CH 2 O 2 
 
 Colorless volatile liquid. 
 
 In red ants and some other 
 
 
 
 
 insects and in some sting- 
 
 
 
 
 ing plants. 
 
 Acetic ... . 
 
 C 2 H 4 O 2 
 
 Colorless pungent liquid. 
 
 Oxidation of alcohol and 
 
 
 
 
 sugar. 
 
 Propionic . . . 
 
 C 3 H f) 2 
 
 Crystalline solid. 
 
 
 Butyric 
 
 C 4 H 8 2 
 
 Colorless liquid of disagree- 
 
 Butter and other animal 
 
 
 
 able odor. 
 
 secretions. 
 
 Valeric 
 
 C 5 H 10 2 
 
 Colorless liquid of disagree- 
 
 Valerian root. 
 
 
 
 able odor. 
 
 
 Caproic .... 
 Enanthylic . . 
 
 CoHi"O 2 
 C 7 H 14 2 
 
 Colorless oily body. 
 Slightly soluble in water; 
 
 Butter and coconut oil. 
 Oxidation of castor oil. 
 
 
 
 has an agreeable odor. 
 
 
 
 
 
 Butter, coconut and castor 
 
 Caprylic .... 
 
 C 8 H 16 O 2 
 
 
 oils. 
 
 Pelargonic . . 
 Capric 
 
 
 Crystalline solid. 
 Crystalline mass having the 
 
 Geranium leaves. 
 Butter and coconut oil. 
 
 
 
 odor of sweat. 
 
 
 Laurie 
 Myristic .... 
 
 Cuuf 8 ol 
 
 Silky crystals. 
 Crystalline scales. 
 
 In coconut oil. 
 In nutmeg and coconut oil. 
 
 Palmitic 
 
 
 Fat-like solid. 
 
 Most natural fats. 
 
 Margaric . . . 
 
 CnH 34 2 
 
 it 11 
 
 
 Stearic 
 
 C 18 H 36 O.> 
 
 
 
 Arachidic. . . 
 
 C 20 H 40 O 2 
 
 White crystalline fatty solid. 
 
 Peanut oil. 
 
 Behenic .... 
 
 C 22 H 44 2 
 
 i < t ii K 
 
 Oil of ben. 
 
 Hyenic 
 
 
 'Resembles cerotic. 
 
 
 Cerotic 
 Mellissic. . . . 
 
 C 27 H5 4 2 
 C 3 oH co O 2 
 
 Crystallises in small grains. 
 
 Free in beeswax. 
 Derived from beeswax. 
 
 Butyric (Tetrylic) Acid, C 3 H 7 ,COOH. This may be 
 obtained from butter-fat, from some fruit flavors, and by 
 
FATTY-ACIDS. 79 
 
 fermentation of sugar with cheese and chalk. It is a 
 colorless liquid having the disagreeable odor of rancid 
 butter. Ethyl butyrate is produced by heating butter- 
 fat with alcoholic solution of sodium hydroxide. The 
 reaction is not known. 
 
 Valeric (Pentylic) Acid, C 4 H 9 COOH, is found in 
 valerian root and in other plants. Four isomeric modifi- 
 cations are possible. The ordinary form is a colorless 
 liquid of a disagreeable odor. Several valerates, often 
 called valerianates, are used in medicine; among these are 
 those of zinc and ammonium. 
 
 Stearic Acid, HC 18 H 35 O 2 , can be obtained from most 
 of the solid animal fats, and from some vegetable fats. It 
 is a white, crystalline body which can be distilled. It is 
 insoluble in water, slightly soluble in alcohol. The white 
 candles called stearin are generally made of stearic acid. 
 Its only use in medicine is with sodium carbonate, with 
 which it forms a soap, a vehicle for the administration of 
 glycerol in suppositories. 
 
 Salts of Fatty-Acids Soaps. By substituting the single 
 atom of replaceable hydrogen of the fatty-acids a series 
 of bodies is obtained all of which might be called "soaps," 
 but it is only with the higher members of the series 
 that the peculiar physical and chemical characters of 
 the soaps are noticeable. The derivatives of the lower 
 members are generally soluble in water, but in the higher 
 members most of the compounds are insoluble, except 
 those formed by potassium, sodium and ammonium. 
 Lead, calcium and zinc, for instance, form insoluble soaps. 
 
 The soluble soaps are those which are valuable for their 
 detergent properties. When sodium hydroxide is used 
 in combination with olive oil, a "castile" soap is produced 
 which is a hard soap. Potassium hydroxide produces 
 
8o ORGANIC CHEMISTRY. 
 
 the so-called soft-soaps; the official soft or green soap (Sapo 
 mollis), being made from potassium hydroxide and linseed 
 oil. Among the insoluble soaps which are of common 
 occurrence may be mentioned : Lead plaster which is lead 
 oleo-stearate, made by saponifying olive oil with lead 
 oxide, glycerol being obtained as a by-product. The so- 
 called Carron oil, made by adding lime water (solution of 
 calcium hydroxide) to linseed oil is an insoluble calcium 
 soap formed with the fatty-acids of linseed oil. 
 
 SUBSTITUTION DERIVATIVES OF THE FATTY-ACIDS. 
 
 The hydrogen that is part of the radicle of these acids 
 may be substituted by members of the chlorine group, 
 particularly by chlorine itself. From acetic acid we get 
 three compounds, which resemble the original acid: 
 
 HC 2 H 3 O 2 Acetic acid. 
 
 HC 2 H 2 C1O 2 Monochloracetic acid. 
 
 HC 2 HC1 2 O 2 Dichloracetic acid. 
 
 HC 2 C1 3 O 2 Trichloracetic acid. 
 
 These compounds are usually obtained by the direct 
 action of chlorine. By indirect means, the use of phos- 
 phoric chloride, PC1 5 , for instance, the chlorine may be 
 made to replace the hydroxyl of the acid ; in this manner 
 the acid properties are removed, and chlorides formed with 
 the acid radicles. Acetic acid gives the following: 
 
 Acetic acid. Acetyl chloride. 
 
 CH 3 COOH + PC1 5 = CH 3 COC1 + POC1 3 + HC1 
 Similar compounds may be obtained with bromine. 
 
OLEFINS OR METHENE SERIES. 8l 
 
 OLEFINS OR METHENE SERIES. 
 
 M ethene, the first member of the series, has not yet been 
 obtained. Ethene, C 2 H 4 , ethylene, the second member of 
 this series, was called, when first discovered, olefiant (oil- 
 making) gas, because it combines with chlorine to form an 
 oily liquid; for this reason the series has been called the 
 olefins. They are dyad radicles, which form alcohols, 
 ethers and other derivatives; but these derivatives are 
 greater in number than from monad radicles, on account 
 of the higher valency. Two series of acids are yielded 
 by the action of oxygen on the alcohol, instead of one, 
 as in the case of the monad radicles. 
 
 The ratio between the weights of the hydrogen and 
 carbon is the same in all members of the series, hence 
 the percentage composition is the same, but the mo- 
 lecular weight increases. The members of the series are 
 polymeric isomers. 
 
 DERIVATIVES OF OLEFINS. The olefins combine di- 
 rectly with the halogens. Ethene dichloride C 2 H 4 C1 2 , 
 was originally called Dutch liquid, because discovered by an 
 association of Dutch chemists. 
 
 By indirect means, oxides esters and hydroxides may be 
 formed. The hydroxides contain two molecules of HO 
 and are known as DIATOMIC ALCOHOLS or GLYCOLS. 
 Each of these alcohols yields by oxidation two acids, 
 one derived by the replacement of two atoms of hydrogen 
 by one atom of oxygen, and the other by the replacement 
 of four atoms of hydrogen by two atoms of oxygen. The 
 first is the lactic acid series; the second, the oxalic acid 
 series. For instance, ethene glycol gives the following: 
 6 
 
82 
 
 ORGANIC CHEMISTRY. 
 
 C 2 H 4 (HO) 2 
 C 2 H 4 (HO) 2 
 
 O 4 
 
 H 2 O 
 
 Glycolic acid. 
 
 HOCH 2 COOH 
 
 Oxalic acid. 
 
 COOHCOOH 
 
 Oxalic acid is, therefore, dicarboxyl. Methene glycol, 
 CH 2 (HO) 2 , has not been obtained. By oxidation it could 
 form but one acid, carbonic, (HO) 2 CO, which may be 
 regarded as the first member of the first series. 
 
 Radicle. 
 
 Oxides, 
 Ethers. 
 
 Hydroxides, 
 Alcohols. 
 
 Acids by first 
 oxidation. 
 
 Acids by second 
 oxidation. 
 
 
 
 
 Glycolic acid. 
 
 Oxalic acid. 
 
 C 2 H 4 
 
 C 2 H 4 
 
 C 2 H 4 (HO) 2 
 
 C 2 H 4 3 
 
 C 2 H 2 4 
 
 
 
 
 Lactic acid. 
 
 Malonic acid. 
 
 C 3 H 6 
 
 C 3 H 6 
 
 C 3 H 6 (HO) 2 
 
 C 3 H 6 O 3 
 
 C 3 H 4 4 
 
 
 
 
 Oxybutvric acid. 
 
 Succinic acid. 
 
 C,H 8 
 
 C 4 H 8 
 
 C 4 H 8 (HO) 2 
 
 C 4 H 8 3 
 
 C 4 H 6 4 
 
 The acids of the first series, containing one molecule 
 of alcoholic hydroxyl and one molecule of carboxyl, are 
 called hydroxy-acids. 
 
 Ethene oxide, C 2 H 4 O, is isomeric (more accurately, 
 metameric), with common aldehyde. It is a three- 
 membered closed chain, the oxygen atom being one mem- 
 ber of the chain (see under " Heterocyclic " compounds). 
 
 The structural relations of ethene (ethylene) glycol and 
 its two acid derivatives, together with two important salts 
 of oxalic acid are shown in the annexed formulas: 
 
 H H 
 
 H 
 
 H H 
 
 U 
 
 H C C H O=C C H 
 
 H H 
 
 Ethene glycol 
 (Dihydroxyethane) 
 
 H 
 
 Glycolic acid. 
 
OLEFINS OR METHENE SERIES. 
 
 H H 
 
 i 
 
 Na H 
 
 O 
 
 Ca 
 
 o A o 
 
 O O 
 O=C C=O O=C C=O O:=C C=O 
 
 Oxalic acid 
 (Dicarboxyl) 
 
 Acid sodium oxalate 
 
 Calcium oxalate 
 
 Acid Derivatives of the Glycols. These are the most 
 important. The first (lactic) series is monobasic, that 
 is, has a single atom of replaceable hydrogen; the second 
 (oxalic series) is dibasic, that is, has two atoms of re- 
 placeable hydrogen. 
 
 LACTIC SERIES. 
 
 Name. 
 
 Formula. 
 
 Source. 
 
 Gly colic . 
 
 CoH.Oo 
 
 By oxidation of ethene glycol 
 
 Lactic . ... 
 
 C,H fi Oo 
 
 By fermentation of milk sugar 
 
 Oxybutyric 
 
 C.HoOo 
 
 By oxidation of butyric acid 
 
 Oxyvaleric 
 
 C,H, n O, 
 
 By oxidation of valeric acid. 
 
 Leucic 
 
 CH'O 
 
 Occurs in animal products ' also 
 
 
 
 formed by decomposition of 
 horn and glue. 
 
 Gly colic acid is found in unripe grapes. It is of no 
 commercial importance. 
 
 Lactic Acid, (HO)C 2 H 4 (COOH). This important acid 
 exists in four modifications. 
 
 Ordinary lactic acid is a product of fermentation of 
 milk sugar and is therefore found in sour milk and 
 koumyss. It is a colorless, syrupy, very sour liquid, which 
 has not yet been obtained in the solid state. It can be 
 obtained in quantity by allowing a mixture of cane sugar, 
 cheese, sour milk and chalk, or zinc oxide to ferment for 
 
84 ORGANIC CHEMISTRY. 
 
 several days. The resulting calcium or zinc lactate can be 
 purified and lactic acid obtained from it. It is optically 
 inactive, but consists of equal parts of dextro- and levoro- 
 tatory forms, which can be separated by several methods. 
 Such separation of isomers is termed "mesotomy" (Gr. 
 cutting midway). Dextrolactic acid occurs in the juice 
 of flesh and is sometimes called sarkolactic acid. 
 
 Ethene-lactic acid is obtained synthetically by several 
 methods. It is optically inactive. The following formu- 
 las show the stereochemistry of these compounds. Asym- 
 metric carbon is present only in one arrangement. 
 
 H 
 
 H O O H H O 
 
 I I II .11 N 
 
 H-C C C O-H H-O C C C O-H 
 
 H H H H 
 
 Active lactic acid Ethene-lactic acid 
 
 Paralactic and ordinary lactic acid (Ethylene lactic acid) 
 
 (Ethylidene lactic acid) 
 
 d + 1 = lactic acid of fermentation 
 
 Several lactates are used in medicine particularly 
 ferrous lactate and strontium lactate. Lactic acid is one 
 of the products of the growth of fungi around the teeth, 
 and is an important factor in dental caries. When lactic 
 acid is heated in dry air, several anhydrides are formed 
 as follows: 
 
 2 C 3 H 6 O 3 - - H 2 O = C 6 H 10 O 5 , lactic anhydride 
 C 6 H 10 5 - H 2 = C 6 H 8 4 , lactide 
 
 Lactide is a stable compound. 
 
OLEFINS OR METHENE SERIES. 85 
 
 Experiment 16. To 5 c.c. of a dilute aqueous solution of phenol 
 add ferric chloride to obtain the characteristic violet reaction. 
 Add to this solution a single drop of lactic acid and observe that 
 the color of the solution changes from violet to a bright canary- 
 yellow. This is Uffelmann's reaction for detecting lactic acid in 
 gastric juice. 
 
 OXALIC SERIES. 
 
 Name. 
 
 Formula. 
 
 Source. 
 
 Oxalic 
 
 HoCoO. 
 
 Oxidation of sugar starch and 
 
 Malonic 
 Succinic 
 
 C 3 H 4 4 
 C 4 H 6 O 4 
 
 cellulose. 
 Oxidation of malic acid. 
 Distillation of amber; oxidation of 
 
 Pyrotartaric .... 
 Adipic 
 Pimelic 
 
 C 5 H 8 4 
 CeH 10 O 4 
 C 7 H 19 O, 
 
 fatty-acids. 
 Action of heat on tartaric acid, 
 nitric on sebacic acid. 
 ' potassium hydroxide on 
 
 Suberic 
 
 0H i /<O A 
 
 camphoric acid. 
 Action of nitric acid on cork or 
 
 Anchoic 
 
 
 castor oil. 
 Action of nitric acid on coconut 
 
 Sebacic 
 
 
 oil. 
 Distillation of oleic acid 
 
 Rocellic 
 
 C 17 H,,O. 
 
 Exists in some lichens. 
 
 
 
 
 Oxalic Acid, (COOH) 2 . The free acid and its salts, 
 especially acid potassium oxalate and calcium oxalate 
 occur in many plants, generally in the form of crystals- 
 called raphides deposited in special cells. It is now 
 made by fusing cellulose, in the form of sawdust, with 
 potassium hydroxide. It is decomposed by strong heat or 
 the action of dehydrating agents with the production of 
 CO 2 , CO and H 2 O. When it is heated with glycerol, 
 formic acid is produced. 
 
 Oxalic acid forms colorless crystals, having the com- 
 position H 2 C 2 O 4 ,2H 2 O. It is freely soluble in water, and is 
 one of the most rapidly fatal poisons known. Death has 
 occurred in ten minutes after administration. Soluble 
 
86 ORGANIC CHEMISTRY. 
 
 oxalates are also poisonous, hence the antidote must be 
 some material that will produce an insoluble compound. 
 Lime is the only available substance. Preparations of the 
 acid are sold under the misleading names of salt of sorrel, 
 and salt of lemon, and used for removing ink stains. 
 
 Cerium oxalate, Ce(C 2 O 4 ) 3 -f 9H 2 O, is the only salt of 
 oxalic acid that is used in medicine. It is a permanent 
 white powder; odorless and tasteless. 
 
 Ammonium oxalate, (NH 4 ) 2 C 2 O 4 , forms white crystals, 
 soluble in water, and much used as a test for calcium 
 compounds. 
 
 Calcium oxalate, CaC 2 O 4 , is colorless and insoluble in 
 water. It is usually found in the urine in microscopic 
 octohedral or dumbbell crystals. In larger masses it 
 constitutes mulberry calculus. 
 
 Experiment 1 7 . Heat cautiously together in a flask 5 grams of 
 sugar and 40 c.c. of nitric acid. After the reaction has ceased 
 and red fumes cease to be evolved, concentrate the liquid, neutral- 
 ise with soda and test for oxalic acid, as in the following experiment : 
 
 Experiment 18. Add a solution of oxalic acid to a dilute solu- 
 tion of calcium chloride or to lime water and observe the white 
 precipitate of calcium oxalate, CaC 2 O 4 . Collect the precipitate, 
 dry and ignite it. The residue is calcium carbonate, CaC 2 O 4 = 
 CaCO 3 + CO. Treat the residue with acetic acid and note the 
 effervescence. 
 
 Experiment 19. Prepare a dilute solution of potassium per- 
 manganate, add an equal volume of solution of oxalic acid, acidu- 
 lated strongly with sulphuric acid, and observe the discharge of color 
 of the permanganate solution according to the following reaction : 
 
 5H 2 C 2 O 4 + K 2 Mn 2 O 8 + 3H 2 SO 4 = 2 MnSO 4 + K 2 SO 4 + 8H 2 O + 
 ioCO 2 
 
 Succinic Acid, C 2 H 4 (COOH) 2 . This occurs in amber 
 and other resins; also in small quantities in some animal 
 secretions. It forms colorless crvstals, soluble in water. 
 
CALIFORNIA COLLEGE 
 
 of PHARMACY 
 
 ACIDS DERIVED FROM TRIATOMIC ALCOHOLS. 
 
 Somewhat related to the series just described, although 
 not necessarily referable to the same radicles, are two 
 important vegetable acids, malic and tartaric. The 
 relation is especially with succinic acid, from which they 
 differ only in amount of oxygen: 
 
 Empirical formulas. 
 
 Succinic C 4 H 6 O 4 
 
 Malic , C 4 H 6 O 5 
 
 Tartaric C 4 H 6 O 6 
 
 Malic Acid, H 2 C 4 H 4 O 5 , occurs in many sour fruits, as 
 apples, pears, mountain ash berries and the fruit of Rkus 
 glabra. It may be made artificially from succinic acid 
 by replacing an atom of H with OH, or from tartaric acid 
 by reduction and removal of O. It is crystalline, sour, 
 soluble in water and alcohol. The malates are mostly 
 soluble in water. Sweet cherries contain potassium 
 malate. The annexed formula will show the presence of 
 asymmetric carbon in malic acid: 
 
 H H H 
 
 AH A A 
 
 O=C C C C=O 
 
 H H 
 
 Malic acid 
 
 Tartaric Acid, (HO) 2 C 2 H 2 (COOH) 2 , is found in many 
 plants, but especially in grapes, in which it exists as acid 
 potassium tartrate, KHC 4 H 4 O 6 . This is somewhat soluble 
 in water, but insoluble in dilute alcohol; and hence, in the 
 manufacture of wine, as the fermentation advances, the 
 
 87 
 
88 ORGANIC CHEMISTRY. 
 
 quantity of alcohol increases, and the tartrate deposits as a 
 red mass called argol or tartar. When this is dissolved in 
 water and purified by crystallisation it constitutes cream 
 of tartar. Tartaric acid is obtained from argol by decom- 
 position with sulphuric acid. It is the dextrorotatory 
 form of four stereochemic isomers, two of which are, 
 respectively, dextro- and levorotatory, and two optically 
 inactive. One of these owes its inactivity to internal 
 antagonism of the asymmetric carbon atoms, the other 
 is a mixture of equivalent quantities of the two active 
 forms. By inoculating a solution of this form with a 
 common mold (Penicillium glaucum) the dextrorotatory 
 form is gradually broken up by the organism, leaving the 
 other form unchanged. This method was discovered by 
 Pasteur to whom the initial investigation in this line is 
 due. There are other methods of mesotomy for these 
 optical isomers. 
 
 Racemic acid. This is the naturally occurring mixture 
 of the two optically active forms. It is found associated 
 with tartaric acid and can be prepared synthetically. 
 
 H H 
 
 O=C C C C=O 
 
 U 
 
 . . 
 
 Tartaric acid 
 
 Acid potassium tartrate, cream of tartar, is a white 
 crystalline body, very sour, and not very soluble in cold 
 water. It is used in baking powders because it liberates 
 CO 2 from alkaline carbonates and acid carbonates. 
 
ACIDS DERIVED FROM TRIATOMIC ALCOHOLS. 89 
 
 Potassium tartrate, K 2 C 4 H 4 O 6 , is called soluble tartar. 
 
 Sodio- potassium tartrate, NaKC 4 H 4 O 6 "; + 4H 2 O is known 
 as Rochelle salt. 
 
 Tartar emetic is made by boiling acid potassium tartrate 
 with antimonous oxide, by which an atom of hydrogen is 
 replaced by the molecule SbO. The formula for tartar 
 emetic is K(SbO)C 4 H 4 O 6 , potassium antimoxyl tartrate. 
 It crystallises with one molecule of water of crystallisation 
 to two molecules of the salt, the formula being 2K(SbO)- 
 C 4 H 4 6 +H 2 0. 
 
 Citric Acid, (HO)C 3 H 4 (COOH) 3 , is the acid present in 
 lemons, limes and oranges, and is also found in some other 
 fruits. It is usually prepared from lemons and limes, 
 which contain from 7 to 10 per cent., but it has also been 
 produced from solutions of cane sugar by the action of 
 certain microscopic fungi. It is normally present in milk. 
 It contains no asymmetric carbon. 
 
 It is a crystalline body, very sour and easily soluble in 
 water, if is used in the preparation of effervescing 
 mixtures, but some of the so-called effervescing citrates 
 contain tartaric instead of citric acid. At a high tem- 
 perature citric acid is decomposed into aconitic acid, 
 C 3 H 3 (COOH) 3 and H 2 O. 
 
 H H H 
 
 OHO 
 
 J. JL 
 
 i.i, 
 
 O H 
 
 H O 
 
 H O C=O 
 
 Citric acid 
 
90 ORGANIC CHEMISTRY. 
 
 METHY-LENE (METHENYL) SERIES. 
 
 These are triad radicles. The first member, CH, meth- 
 enyl, may be regarded as existing in chloroform. The 
 most important member of the group is trite nyl, C 3 H 5 , also 
 called propenyl, propylene and glyceryl. Its hydroxide, 
 C 3 H 5 (HO) 3 , is glycerol. Many of the common oils and 
 fats are propenyl esters, and when treated with alkalies, 
 such as sodium hydroxide, are broken up; a new salt and 
 propenyl hydroxide are formed. On propenyl stearate (one 
 of the ingredients of common animal fat) sodium hydrox- 
 ide common lye would act thus: 
 
 Propenyl sieaiate. Sodium stearate. Glycerol. 
 
 (C 3 H 5 )(C 18 H 35 2 ) 3 + 3 NaHO = 3 NaC 18 H 35 O 2 + C 3 H 5 (HO) 3 
 
 Sodium stearate is a soap, and the process is saponi- 
 fication. The formation of glycerol can also be brought 
 about by the use of superheated steam. This method is 
 now generally used, since it gives the fatty-adds in the 
 free condition, thus: 
 
 C 3 H 5 (C 18 H 35 2 ) 3 + 3 H 2 == C 3 H 5 (HO) 3 + 3 HC 18 H 35 O 2 
 
 Glycerol (glycerin), C 3 H 5 (HO) 3 . Pure glycerol is a 
 colorless, viscid liquid, miscible in all proportions with 
 water. Sp. gr. 1.2659. It has a sweet taste, absorbs 
 water from the air, but does not otherwise change. Under 
 certain conditions of pressure it can be distilled without 
 decomposition, but under ordinary conditions it decom- 
 poses at the boiling point. It solidifies at about 40. 
 It dissolves a great many substances, standing next 
 to water in its range of solvent powers. It is produced 
 in small quantity during the fermentation of sugar, hence 
 is often found in ordinary liquors. It is sometimes called 
 
METHYLENE (METHENYL) SERIES. QI 
 
 the ''sweet principle of fats," but it does not exist in 
 fats, and possesses no chemical analogy to them. It is 
 an alcohol, and is probably somewhat analogous to the 
 sugars. Its use, therefore, as an application to the skin 
 as a substitute for the emollient oils has no chemical 
 justification, and owing to its strong affinity for water, 
 which it abstracts from the tissues, it often produces 
 irritation when applied in the undiluted state. 
 
 When treated with strong nitric acid, it forms propenyl 
 nitrate, C 3 H 5 (NO 3 ) 3 , known as nitro glycerin. This is 
 a high explosive. It is now extensively used as a blast- 
 ing agent, being generally mixed with some inert power 
 such as paper pulp or diatomaceous earth, in which form 
 it constitutes dynamite. 
 
 H H H 
 
 C H 
 
 -i. A JL J. 
 
 H-U 
 
 A 
 
 H H H 
 
 Glycerol 
 
 FATS AND FIXED OILS. 
 
 The fats and fixed oils are almost all esters of propenyl 
 (glyceryl). Most of the natural forms are mixtures of two 
 or more distinct esters. Names are applied to them ac- 
 cording to the acid from which the ester is derived. (See 
 below.) The fixed oils are fats with a low melting point, 
 and may be divided into two classes; drying oils, which 
 absorb oxygen from the air, and become hard and resinous, 
 
Q2 ORGANIC CHEMISTRY. 
 
 such as linseed and poppy oil; non-drying oils, which 
 remain fluid, as castor and sperm oils. Many fats and 
 oils undergo partial decomposition in the air, producing 
 acids, the condition being known as rancidity. When 
 an alkali is added to a fat, decomposition takes place, a 
 salt is formed, constituting a soap, and glycerol is pro- 
 duced. Soaps produced by potassium hydroxide are usu- 
 ally soft; those from sodium hydroxide hard ; those 
 made from other oxides are mostly insoluble in water. 
 This latter fact explains the curdling action of limestone 
 waters. The calcium and magnesium compounds in these 
 waters produce insoluble soa'ps. When soluble soaps 
 are treated with cold water they decompose into acid salt, 
 which precipitates and makes the soapsuds, and a basic 
 salt, which dissolves and gives the cleansing action. 
 
 The fatty-acids may be obtained by adding a strong 
 acid to ordinary soaps. 
 
 The fats are all insoluble in water, but are soluble in 
 ether, chloroform, benzene, petroleum spirit and carbon 
 disulphide. They are decomposed by heat, and conse- 
 quently cannot, under ordinary circumstances, be dis- 
 tilled. 
 
 The proximate constituents of the common fats are 
 given under condensed names, the significance of which 
 is as follows: 
 
 Stearin is propenyl stearate. 
 Palmitin is propenyl palmitate. 
 Margarin is propenyl margarate. 
 Butyrin is propenyl butyrate. 
 Olein is propenyl oleate. 
 
 Oleic acid is not a member of the same series with the 
 other acids. It belongs to a series beginning with acrylic 
 acid, C 3 H 4 O 2 , and is elsewhere described. 
 
FATS AND FIXED OILS. 93 
 
 Glycero phosphoric Acids. Several of these are possible, 
 but the only one of importance is that having the formula 
 C 3 H 5 (HO) 2 H 2 PO 4 . The structural formula of this is 
 shown in connection with that for lecithin in the section 
 on Proteids. Some of the complex esters that are found in 
 higher tissues, e. g. t brain, nerve-tissue and egg-yolk, are 
 derivatives of this acid. Calcium, sodium and strychnine 
 glycerophosphates are used in medicine. The acid can be 
 prepared by the action of glycerol on orthophosphoric acid. 
 
 Experiment 20. Heat together in an evaporating dish, 40 
 grams of linseed oil, 9 grams of potassium hydroxide, 5 c.c. of 
 alcohol and 50 c.c. of water. * Continue the heat, with constant 
 stirring, until a small portion of the mixture is found to be com- 
 pletely soluble in hot water. This process is called saponification 
 and is analogous to the method used in making Sapo mollis of the 
 Pharmacopoeia. The potassium hydroxide reacts with the linseed 
 oil, forming soap and glycerol. By using olive oil and sodium 
 hydroxide a hard or soda-soap is obtained which may be precipitated 
 from its aqueous solution by the addition of sodium chloride which 
 causes it to separate in the form of curdy masses. 
 
 Experiment 2 1 . Dissolve a small quantity of the soap made in 
 the previous experiment in water, and add it gradually to a solu- 
 tion of copper sulphate (i to 20). The separation of an insoluble 
 copper-soap will take place. The addition of the soap solution 
 to a solution of calcium chloride will cause the precipitation of an 
 insoluble calcium-soap. 
 
 Experiment 22. Dissolve about 5 grams of soap in 100 c.c. of 
 water by the aid of heat and add to the solution 5 c.c. of diluted 
 sulphuric acid. The fatty-acids of the soap will separate in the 
 form of an oily layer upon the surface of the liquid. 
 
 Experiment 23. Heat about 5 c.c. of ethyl acetate in a flask, 
 connected with a reflex condenser, with an excess of sodium hy- 
 droxide (about 4 grams) , dissolved in a little water. The odor of 
 ethyl acetate disappears owing to saponification with the forma- 
 tion of sodium acetate and alcohol, according to the following 
 reaction : 
 
 C 2 H 5 (C 2 H 3 O 2 ) + NaOH = Na(C 2 H 3 O 2 ) + C 2 H 5 OH 
 
94 ORGANIC CHEMISTRY. 
 
 Experiment 24. Melt about 10 grams of butter in a testtube 
 by immersing it in boiling water; pour off about 2 c.c. of the 
 melted butter into another testtube and saponify by boiling for 
 a few moments with an alcoholic solution of sodium hydroxide. 
 After the saponification is complete, evaporate the solution to 
 dryness on the water bath and redissolve it in a small quantity of 
 water. Add an excess of dilute sulphuric acid and heat. Observe 
 the odor which is evolved. This is due to the volatile acids of 
 the butter, such as butyric, caproic and their homologues; the 
 greater portion of the fatty-acids of the butter, being non- volatile, 
 remains floating on the surface of the liquid as an oily layer. 
 
 Experiment 25. Boil together, in an evaporating dish, 6.4 grams 
 of lead monoxide, 12 grams of olive oil and 5 c.c. of water, re- 
 placing the water from time to tim as it is lost by evaporation. 
 A thick tenacious compound is formed which solidifies upon cool- 
 ing. This is the official lead plaster, lead oleopalmitate. Observe 
 the sweetish taste of the water with which the compound has been 
 boiled, due to glycerol formed in the reaction, as follows: 
 
 2(C 3 H 5 C 18 H 33 O 2 ) 3 + 3 PbO + 3 H 2 O 
 
 1 33 2 ) 2 + 2 C 3 H 5 (HO) 3 
 
 Allyl and Derivatives. Allyl, C 3 H 5 , is isomeric with pro- 
 penyl, but is a monad, the carbon atoms neutralising the 
 valency of each other more completely than in the case 
 of propenyl. By structural formulas the difference may 
 be thus represented : 
 
 Propenyl, triad. Allyl, monad. 
 
 H H H H 
 
 III II 
 
 C C C H C=C C 
 
 III III 
 
 H H H H H 
 
 Allyl alcohol is C 3 H 5 HO. It is obtained by the dis- 
 tillation of glycerol in the presence. of oxalic acid which 
 acts as a dehydrolysing and reducing agent. Allyl is 
 interesting on account of the occurrence in nature of two 
 of its compounds, allyl sulphide, (C 3 H 5 ) 2 S, which is the 
 
FATS AND FIXED OILS. 95 
 
 essential oil of garlic, and allyl thiocyanate, C 3 H 5 CNS, 
 volatile oil of mustard. Allyl aldehyde, C 3 H 4 O, acrolein, 
 is one of the products of the decomposition of fats by heat, 
 and is the main cause of the irritating vapors which are 
 caused by such decomposition. It is formed by the dry 
 distillation of glycerol according to the following reaction : 
 
 C 3 H 5 (OH) 3 == C 3 H 4 + 2 H 2 
 
 Experiment 26. Heat about 5 c.c. of glycerol in a dry testtube 
 and observe the irritating vapors of acrolein, C 3 H 4 O, that are 
 evolved. 
 
 The oxidation of allyl aldehyde gives acrylic acid, which 
 is the first member of a series of acids derived from some 
 of the fats. The most important of this list is oleic acid. 
 
 Oleic acid, C 17 H 33 (COOH), exists in most natural fats 
 and non-drying oils as olein, propenyl oleate. Above 
 15 it is a clear liquid, lighter than water, and insoluble 
 in it, but soluble in alcohol and ether. Crude oleic acid, 
 is used in soap making, under the name of red oil. Vari- 
 ous oleates, e. g. t copper, bismuth, zinc and mercury 
 oleates, are now used in medicine to produce the physio- 
 logical effect of the medicament by local application. 
 They are usually prepared by the reaction of sodium 
 oleate with some suitable compound. Thus, copper 
 oleate is formed by precipitating solution of copper sul- 
 phate with solution of sodium oleate. 
 
 The derivatives of this series are often termed un- 
 saturated compounds because they are capable of taking 
 up negatives without substitution of hydrogen. The latent 
 valency of the group = C = C =, which is in all of them, is 
 developed. Iodine is especially adapted to this action and 
 the proportion of it taken up under specified conditions 
 is known as the "iodine number." It is an important 
 
9 6 
 
 ORGANIC CHEMISTRY. 
 
 datum in the analytic examination of fatty substances, 
 tar and petroleum products. Some of the fatty bodies 
 containing these unsaturated groups absorb oxygen rather 
 rapidly from the air, becoming viscous. This is commonly 
 termed "drying" and is a property of the oils used in 
 the preparation of paints. 
 
 ACETYLENE SERIES. 
 
 This is a series of unsaturated radicles of which the first 
 member, Methine, is C. The second member, Ethine, 
 more commonly known as acetylene, has the formula 
 C 2 H 2 . The structural formula may be expressed thus : 
 
 C H 
 
 III 
 C H 
 
 The production of acetylene by the direct combination 
 of carbon and hydrogen is an example of absolute synthesis, 
 
 CH=CH 
 
 FIG. 10. 
 
 since both materials are obtainable from inorganic sources. 
 The apparatus is shown in Fig. 10. Hydrogen is allowed 
 to flow through the flask while a succession of electric 
 
ACETYLENE SERIES. 97 
 
 sparks is passed through the carbon poles. Acetylene 
 flows out at the other opening. From acetylene many 
 other organic bodies can be made by synthesis. 
 
 Other members of the series, of less importance, are: 
 Allylene C 3 H 4 , Butine C 4 H 6 , Pentine C 5 H 8 and Hexine 
 C 6 H 10 . The members of this series are produced in the 
 destructive distillation of many organic compounds. 
 Acetylene is produced by a number of other methods, 
 involving the reduction of methane, ethane, ethylene, etc. 
 The incomplete combustion of illuminating gas, as when 
 the flame in a bunsen burner or gas stove strikes back and 
 burns at the base, yields some acetylene. Acetylene 
 is produced commercially for illuminating purposes by 
 the decomposition of metallic carbides (usually calcium 
 carbide, CaC 2 ) with water. Acetylene is a colorless gas 
 
 CaC 2 + 2H 2 O == Ca(HO) 2 + C 2 H 2 
 
 with a peculiar penetrating odor. It burns with a sooty 
 flame from an ordinary burner, but with specially con- 
 structed burners a flame is produced which is brighter 
 and more intense than the ordinary illuminating-gas flame. 
 Acetylene can be liquefied by cold and pressure. The 
 liquid is liable to explode. Acetylene dissolves freely in 
 acetone ; the solution is stated to be not explosive. 
 
 The hydrogen of acetylene can be replaced by strong 
 positives producing carbides. The compounds formed by 
 members of the potassium and calcium groups are stable, 
 except in presence of water and alcohol, but those of 
 silver and copper are explosive. Although these com- 
 pounds are simply carbides, yet as they are obtained by 
 reactions with acetylene, an organic body, they are classed 
 as organic compounds. This is, therefore, an instance of 
 the indefiniteness of the term organic. 
 7 
 
98 ORGANIC CHEMISTRY. 
 
 The alcohols of this series are but little known. The 
 only one of interest is: 
 
 Propargyl alcohol, Propine hydroxide. The structural 
 formula of this is annexed. It is a mobile liquid with an 
 agreeable odor. It forms silver and copper compounds by 
 exchanging hydrogen for these elements, but not the 
 hydroxyl-hydrogen. As with the acetylene derivatives, 
 it is the hydrogen that is attached to the triple-linked 
 carbon that is replaced. 
 
 H 
 
 H C=C C O H 
 
 Propanryl alcohol 
 
 Experiment 27. Add a small fragment of calcium carbide, about 
 i gram, to about 500 c.c. of water contained in a large evaporating 
 dish. Apply a lighted taper to the gas which is evolved and 
 observe its ready inflammability. This gas is acetylene. By 
 generating the gas in a flask and allowing it to pass into an am- 
 moniacal solution of cuprous chloride, a reddish-brown precipitate 
 of copper carbide is formed, which is explosive when dry. 
 
 Experiment 28. Add a small fragment of calcium carbide to 
 about 5 c.c. of a saturated solution of zinc chloride contained in a 
 testtube. Acetylene is not evolved as is the case when pure water 
 is used. 
 
CARBOHYDRATES. 
 
 This term was originally applied to sugars, starch and 
 allied bodies, because they contain carbon, hydrogen and 
 oxygen, the latter two being in the proportion in which 
 they exist in water, namely, H 2 to O. Two formulas 
 will illustrate this : 
 
 Cane sugar C 12 H 2 2O U 
 
 Dextrose C 6 H 12 O 8 
 
 This limitation is now known to be inapplicable. Sub- 
 stances strictly analogous to the true carbohydrates, and 
 exhibiting other ratios of hydrogen to oxygen have been 
 discovered. Some compounds that exhibit this ratio, 
 acetic acid, C 2 H 4 O 2 , for instance, are not included in the 
 group. The term is, however, too well fixed in the nomen- 
 clature of chemistry to be displaced at present. 
 
 The number of substances included within this group is 
 large. They are mostly of vegetable origin, soluble in 
 water, optically active and readily susceptible to the action 
 of enzyms and microorganisms, by which they are at first 
 usually hydrolysed and then split into simpler forms, 
 changes that are exemplified in the common forms of 
 fermentation. 
 
 The group of carbohydrates is subdivided as follows: 
 
 Examples. 
 
 MONOSACCHARIDS Dextrose, arabinose. 
 
 DISACCHARIDS Sucrose, lactose. 
 
 TRISACCHARIDS Raffinose. 
 
 POLYSACCHARIDS Starch, cellulose. 
 
 99 
 
100 ORGANIC CHEMISTRY. 
 
 The carbohydrates have moderate reducing powers, 
 especially in alkaline solution. Many of them form with 
 phenylhydrazin characteristic crystalline precipitates called 
 "osazones." 
 
 Hydroxyl is a predominating group in the carbohydrates ; 
 several molecules are present in even comparatively simple 
 forms. They are, therefore, as a class, alcoholic. They 
 break down through the action of certain fungi, especially 
 yeasts, into simpler bodies which are distinctly alcoholic, 
 such as ethyl alcohol, some forms of butyl and amyl alcohol, 
 and glycerol. Methyl alcohol does not appear to be a result 
 of these actions. Many carbohydrates show feebly the 
 properties of acids, but they are not true acids. Several 
 of the sugars, for instance, will form compounds with 
 calcium oxide. A solution of cane sugar will dissolve 
 a notable amount of lime ; the compound formed has been 
 termed calcium saccharate or saccharate of lime. 
 
 Aldehyde and ketone groups are frequently present in 
 the carbohydrates. The structural formulas of several 
 hexoses are accurately known and some of them have been 
 obtained synthetically. One of the synthetic methods is 
 by reactions between glycerose and formaldehyde. A 
 carbohydrate that contains an aldehydic group is called 
 an aldose; a carbohydrate that contains a ketone group 
 is called a ketose. A carbohydrate may contain all three 
 of these groupings, and be, therefore, aldehydic, alcoholic 
 and ketonic, a condition that might be condensed into 
 " aldalcoketose " to show the three types and the carbohy- 
 drate structure. 
 
 MONOSACCHARIDS. Under the group monosaccharids 
 are included substances containing different numbers of 
 carbon atoms, indicated by the terms monose, diose, 
 triose, etc. Of these the pentoses and hexoses are the 
 
CARBOHYDRATES. IOI 
 
 most important. Formaldehyde may be considered a 
 monose. 
 
 Glycerose, C 3 H 6 O 3 , is apparently a triose, but is a mixture 
 of two carbohydrates obtained by the oxidation of glycerol. 
 One of these is an aldose, the first glycerol aldehyde, that is, 
 the product obtained by removing H 2 from glycerol with- 
 out introducing oxygen; the other, a ketose, is the ketone 
 derivative of glycerol. The formulas of these derivatives 
 are, respectively: 
 
 HCO HCOH 
 
 HCOH HCO 
 
 I I 
 
 H 2 COH H 2 COH 
 
 Aldehyde Ketone 
 
 Glycerose is of no practical interest, but its application 
 in the synthesis of carbohydrates has given it theoretic 
 importance. 
 
 Pentoses exist in many plant tissues and have an impor- 
 tant bearing on the nutritive value of vegetable materials, 
 but the details belong to physiology rather than chemistry. 
 
 HEXOSES. Two important hexoses require detailed 
 consideration : 
 
 Dextrose, Glucose, Grape sugar, C 6 H 12 O 6 . This exists 
 in many fruit juices and in honey. It is present in small 
 amount in many animal fluids and excretions; in some 
 diseases the amount is greatly increased. In fruit juices 
 and honey it is associated with levulose. Dextrose can be 
 obtained by the hydrolysis of many carbohydrates by 
 dilute acids or enzyms. Starch, dextrin, cellulose and 
 cane sugar are easily hydrolysed in this manner. 
 
 The principal commercial source of dextrose is by the 
 hydrolysis of starch, usually corn starch, by dilute sul- 
 
102 ORGANIC CHEMISTRY. 
 
 phuric acid. If the resulting solution is not concentrated 
 beyond the syrupy condition, it will contain, in addition 
 to dextrose, maltose, dextrin and several unfermentable 
 carbohydrates not yet clearly isolated. If the material 
 be evaporated to solid form, it will consist almost entirely 
 of dextrose. The syrupy liquid is commercially always 
 called "glucose" and the solid form "grape sugar." 
 
 Pure dextrose is a white, crystalline substance, freely 
 soluble in water, to which it imparts moderate sweetness. 
 The solution has strong dextrorotatory power and is easily 
 fermentable by yeast into carbon dioxide and alcohol. 
 In alkaline solution, dextrose has marked reducing power, 
 liberating copper, lead, silver, gold and platinum from 
 their compounds. It forms with phenylhydrazin an 
 osazone that crystallises in yellow stellate tufts. 
 
 Commercial glucose is largely used as a substitute for 
 other carbohydrates in the fermentation industries, and 
 also as a substitute and adulterant for honey, molasses and 
 maple syrup. 
 
 Levulose, C 6 H 12 O 6 , d-Fructose, Fruit sugar. This is 
 associated with dextrose in fruit juices and in honey, and 
 is produced in equal amount with dextrose in the hydrolysis 
 of sucrose. It can be obtained pure by heating inulin with 
 water at the boiling point for twenty-four hours. 
 
 Levulose is soluble in water, forming a sweet liquid that 
 is strongly levorotatory at ordinary temperatures; less so 
 when hot. It ferments with yeast to carbon dioxide 
 and alcohol, but not so readily as dextrose, hence many 
 fruit-juices, become levorotatory when fermented, the 
 dextrose being removed much faster than the levulose. 
 
 Notwithstanding the strong levorotatory power of 
 ordinary levulose, it is, on account of certain structural 
 relations, usually termed d-fructose. 
 
CARBOHYDRATES. 103 
 
 Ordinary dextrose and levulose are alcohols, but are not 
 stereo-isomers. The former is an aldehyde, the latter is a 
 ketone. There is, therefore, a form of dextrose having 
 left-handed rotation and one of levulose having right- 
 handed rotation; in fact, theory indicates, and research 
 has confirmed, the existence of numerous isomeric hexoses 
 and derivatives. The annexed formulas show the struc- 
 ture of some of these bodies. Asymmetric carbon is present 
 in all. In forming osazones, dextrose and levulose lose 
 the characteristic groupings, that is, dextrose loses the 
 aldehyde group and levulose loses the ketone group. 
 Hence these hexoses, though not stereo-isomers, yield the 
 same osazone. 
 
 H H 
 
 H O C H H O C H 
 
 H O C H 0=C 
 
 H O C H H O C H 
 
 H O C H H O C H 
 
 H O C H H O C H 
 
 O=C H O C H 
 
 A A 
 
 Dextrose Levulose 
 
104 ORGANIC CHEMISTRY. 
 
 H O 
 
 I II 
 
 O=C H O C 
 
 H O C H H C O H 
 
 H O C H H C O H 
 
 H O C H H C O H 
 
 H O C H H C O H 
 
 C = O H O i 
 
 6 !l 
 
 A 
 
 Glycuronic acid Saccharic and Mucic acids 
 
 It will be noted that glycuronic acid is an alcohol, 
 aldehyde and acid. Saccharic and mucic acids which 
 are products of oxidation of several carbohydrates and 
 stereo-isomers , are alcoholic and acid only. 
 
 HEXOSE ALCOHOLS. These contain hydroxyl groups 
 but no aldehydic nor ketonic groups. They resemble 
 the ordinary hexoses in many ways but do not reduce 
 Fehling's solution and are not fermented by yeast. The 
 most important is : 
 
 Mannite, Mannitol, C 6 H 14 O 6 , which is seen not to cor- 
 respond in its empirical formula to the ordinary definition 
 of a carbohydrate. Mannite exists in three isomeric 
 forms, dextro- and levorotatory and inactive. The dextro- 
 rotatory 'form is a natural product, occurring in several 
 plants, especially in the manna, an exudation from Fraxi- 
 
CARBOHYDRATES. 105 
 
 nits ornus. It may be prepared synthetically by the action 
 of sodium amalgam upon levulose. 
 
 Sorbite, from mountain ash berries, and dulcite, from a 
 manna from Madagascar, are similar in composition to 
 mannite. Care must be taken not to mistake the ter- 
 mination in these names for the syllable used in the names 
 of some salts. The terms sorbitol and dulcitol would be 
 preferable for these bodies. 
 
 DISACCHARIDS. Sucrose, Cane sugar, C 12 H 22 O U . This 
 exists in the juices of many plants, but is commercially 
 obtained from few sources: sugar-cane, beet -root, maple 
 and sorghum. It is a colorless solid, easily crystallised 
 and very soluble in water. The solution is very sweet and 
 has high dextrorotatory power. It does not reduce 
 Fehling's solution, nor form a precipitate with phenyl- 
 hydrazin. It ferments readily with yeast, but this effect 
 is preceded by a hydrolysis under the influence of an 
 enzym present in the yeast-cell. By this hydrolysis, one 
 molecule of sucrose takes up one molecule of water, and 
 divides into one molecule of dextrose and one of levulose. 
 The equation of the reaction is : 
 
 C 12 H 22 U + H 2 == C 6 H 12 6 + C 6 H 12 6 
 
 The proportions by weight are 95 parts of sucrose to 5 
 parts of water, yielding 50 parts of dextrose and 50 parts of 
 levulose. As the specific rotatory power of levulose is, at 
 ordinary temperatures, higher than that of dextrose, the 
 resulting mixture is slightly levorotatory, and is termed 
 "invert sugar." The same transformation can be brought 
 about by the action of dilute acids and many mineral 
 salts. It is technically known as an "inversion." The 
 yeast-enzym that inverts sucrose is called "invertase." 
 The fermentation that ensues is produced by other en- 
 
106 ORGANIC CHEMISTRY. 
 
 zyms not yet definitely isolated, and affects the dextrose 
 more actively than the levulose. 
 
 Maltose, C 12 H 22 O n , is produced together with dex- 
 trins by the action of common enzyms on starch. It is 
 abundantly present in malt. It is sweet, soluble in water, 
 readily fermentable with yeast, reduces Fehling's solution 
 and forms a characteristic osazone. 
 
 Lactose, C 12 H 22 O U , is the characteristic carbohydrate 
 of cow's milk. It probably exists in the milk of many 
 other animals. Richmond obtained from the milk of a 
 species of buffalo, domesticated in Egypt, a similar body 
 to which he gave the name "tewfikose." 
 
 Ordinary lactose, obtained from the whey of cow's milk, 
 crystallises in colorless, gritty masses moderately soluble 
 in cold water and with slight sweetness. The solution 
 ferments readily to lactic acid, but yields alcohol only under 
 the influence of special ferments. In alkaline solution, 
 lactose reduces compounds of silver and copper promptly. 
 It yields a characteristic osazone and differs from sucrose 
 in not being carbonised by strong sulphuric acid, and in 
 reducing Fehling's solution. 
 
 The principal medicinal use of lactose is in the prepara- 
 tion of tablets and triturates of powerful drugs. In its 
 ordinary form it is associated with one molecule of water 
 of crystallisation, which may be driven out by gentle 
 heating. A freshly made solution in water shows excep- 
 tionally high optical activity (termed ' ' birotation " ) but on 
 standing for some hours, or promptly on boiling, the normal 
 rotating power is developed. Boiling with sulphuric acid 
 slowly hydrolyses lactose into a mixture of equal parts of 
 two hexoses, ordinary dextrose and galactose. 
 
 The TRISACCHARID, Raffinose, is found in association with 
 beet sugar. 
 
CARBOHYDRATES. IOJ 
 
 POLYS ACCHARIDS. Cellulose, wC 6 H 10 O 5 is the colorless 
 material of woody fibre. It is seen in cotton or linen in a 
 nearly pure form. It dissolves in an ammoniacal solution 
 of cupric hydroxide but is insoluble in water, ether or 
 alcohol. Strong sulphuric acid converts it either into a 
 soluble substance, like dextrin, or into a substance, giving 
 a blue color with iodine. By long-continued action of 
 dilute sulphuric acid, cellulose is converted into dextrose. 
 
 Paper is nearly pure cellulose obtained by boiling vege- 
 table structures with solutions that dissolve the cementing 
 materials. For the best grades of paper, made from 
 linen and cotton, weak solutions of sodium hydroxide in 
 open vessels are used, but much paper is made from wood, 
 by boiling with strong solutions of sodium hydroxide or 
 magnesium sulphite under pressure. The inferior grades 
 of commercial paper contain much ground wood not 
 chemically treated. 
 
 When paper is treated for a short time with a cold 
 mixture of two volumes of sulphuric acid and one of water, 
 it becomes tough and waterproof, and is termed parchment 
 paper. 
 
 Cellulose may be dissolved and reprecipitated. By 
 mechanical methods the precipitate may be obtained in 
 threads or thin sheets, thus producing artificial textile 
 materials. 
 
 Pyroxylin, Gun-cotton. Cellulose yields with nitric 
 acid a series of nitric esters, having explosive properties. 
 The composition differs with the strength of the acid, 
 temperature and time of immersion. All the products 
 retain the general physical appearance of the original 
 material, but become rapidly combustible, burn with a 
 bright smokeless flame disengage much gas, and leave no 
 appreciable residue. They dissolve, or gelatinise, in 
 
108 ORGANIC CHEMISTRY. 
 
 liquids which do not affect cellulose. When the degree 
 of nitration is low, e. g., the composition, wC 6 H 8 (NO 2 ) 2 O 5 , 
 the product is soluble in a mixture of alcohol and ether 
 and is called soluble or negative cotton. The latter term 
 refers to its use in preparing photographic negatives. 
 When the formula contains larger proportions of the 
 nitric acid radicle, the material is highly explosive, less 
 soluble and is known as gun-cotton. It is used alone as an 
 explosive and also in the preparation of smokeless powders. 
 
 Collodion is formed by dissolving pyroxylin in a mixture 
 of ether and alcohol. This is called plain collodion. 
 
 Celluloid is a mixture of pyroxylin and camphor. 
 
 Glycogen. This is an animal product and is a white, 
 amorphous powder, which gives a brown color with iodine 
 and by the action of ferments or dilute acids is converted 
 into dextrose. It therefore resembles starch, but is solu- 
 ble in cold water. 
 
 Starch. This term is applied to a carbohydrate found 
 widely distributed in the vegetable kingdom, in different 
 tissues, but especially seeds, rhizomes and tubers. It is 
 intimately connected with the formation of the cellular 
 structure of vegetables. The conditions of its develop- 
 ment have been carefully studied owing to its importance 
 in vegetable physiology. It is not unlikely that the first 
 step in its formation is the synthesis of formaldehyde 
 under the influence of sunlight in accordance with the 
 following equation: 
 
 CO 2 + H 2 O = CH 2 + O 
 
 From the formaldehyde, by polymerisation, complex 
 carbohydrates and finally starch is produced. 
 
 The percentage composition of starch corresponds to the 
 empirical formula C 6 H 10 O 5 ; the molecular weight is un- 
 
CARBOHYDRATES. IOQ 
 
 known but is certainly high. The rational formula is also 
 unknown. 
 
 Starch is deposited in the cells of plants in minute 
 granules which are sufficiently characteristic in form to 
 permit the source of the starch to be recognised by micro- 
 scopic examination. In most cases, the granules are spher- 
 ical or spheroidal. They are often marked by concentric 
 rings and by a spot, termed the hilum. 
 
 Starch is not appreciably soluble in cold water; hot 
 water breaks up the granules, dissolves some of the material 
 and forms with the remainder a jelly of very low diffusive 
 power. The solution has high dextrorotatory power. 
 With free iodine, starch produces a deep blue compound, 
 sometimes called starch iodide, but the exact nature of it 
 is not known. It is dissociated by heating the liquid, the 
 mixture becoming colorless, but the color returns on cool- 
 ing. The solid starch also gives the blue with iodine. 
 
 Many enzyms, especially those of malt, saliva and pan- 
 creatic secretion, quickly convert starch -jelly by hydrolysis 
 into a mixture of maltose and dextrin. Dilute acids also 
 hydrolyse starch, producing much dextrose with some 
 dextrin. 
 
 Inulin is a carbohydrate that exists in the roots of many 
 Compositae, such as dahlia and chicory. By boiling with 
 water for some time it is completely converted into levulose. 
 
 Dextrin. This term includes several substances that 
 have not been clearly distinguished. Their composition 
 corresponds to the formula nC 6 H 10 O 5 . They are produced 
 from starch by direct heating with water and by hydrolysis 
 with dilute" acids and many enzyms. They are amor- 
 phous, light yellow powders, insoluble in alcohol, soluble 
 in water, forming an adhesive mucilage. The solution is 
 strongly dextrorotatory and does not reduce Fehling's 
 
HO ORGANIC CHEMISTRY. 
 
 solution. By boiling with dilute acids, the dextrin may 
 be converted into dextrose. 
 
 The dextrin obtained by heating starch with water 
 under pressure is sometimes called British gum. It is 
 used as an adhesive. 
 
 Gum Arabic, an exudation from species of Acacia, 
 consists chiefly of the calcium and magnesium arabates. 
 It is used in the preparation of mucilage. 
 
 Gum Tragacanth. This is composed of several carbo- 
 hydrates, some of which are soluble in water and others 
 that do not dissolve, but absorb water in large amount and 
 swell, making an adhesive paste. 
 
 Several vegetable gelatinising materials, such as agar- 
 agar, are probably carbohydrates or closely related to 
 them. 
 
 Experiment 29. Prepare starch solution as follows: (Arrow-root 
 starch is best but corn starch will serve.) Fifty c.c. of water 
 are brought to the boiling point ; a few grams of starch are stirred 
 well with 10 c.c. of cold water and this mixture poured into the 
 boiling water with constant stirring. The liquid is allowed to 
 become quite cold. Portions 'of about 10 c.c. are used for the 
 experiments. 
 
 Experiment 30. Test a portion of the starch solution with solu- 
 tion of potassium iodide; no color will appear. Add a few drops 
 of solution of iodine; a blue color at once appears. Heat the 
 mixture just to boiling; it will become paler or colorless, and on 
 cooling the color will return. The compound formed by the 
 starch and iodine is apparently dissociated by heat. 
 
 Experiment 31. Add to a portion of the starch solution a small 
 amount of either diastase, takadiastase, pancreatic extract or 
 saliva, and allow the mixture to stand for a few moments. Test 
 portions of about i c.c. every few minutes with iodine solution. 
 The starch reaction will soon be replaced by a dark, brownish 
 color, which will soon be followed by a reddish brown, indicating 
 the completion of the hydrolysis. (See under " Enzyms.") 
 
 Experiment 32. Add 10 c.c. of the starch solution to 10 c.c. 
 
CARBOHYDRATES. Ill 
 
 of water and a few drops of sulphuric acid. Boil the mixture for 
 five or ten minutes, cool, add slaked lime in small portions until 
 litmus paper is not reddened by the liquid, filter and test for 
 reducing sugar as noted below. 
 
 Experiment 33. Treat starch solution with any one of the 
 enzyms noted in Experiment 31 and test the resulting mixture 
 for reducing sugar. 
 
 Experiment 34. Make separate solutions of sucrose, dextrose 
 and lactose by dissolving about 5 grams of each in 50 c.c. of water. 
 The water may be heated if necessary to hasten the solution, but 
 should be allowed to cool. For the dextrose solution, the common 
 glucose or grape-sugar will answer. Portions of 10 c.c. of each of 
 these should be taken for the experiment. Each experiment given 
 below should be repeated with each sugar. 
 
 Experiment 35. Test the reducing action by boiling with copper 
 sulphate rendered alkaline with sodium hydroxide solution. 
 
 Experiment 36. Test the action by boiling with a pinch of bis- 
 muth subnitrate and sodium hydroxide solution. 
 
 Experiment 37. Test the reducing action with solution of 
 silver nitrate rendered alkaline with ammonium hydroxide. 
 
 Experiment 38. Make a solution of 10 grams of sucrose in 100 
 c.c. of water, and divide it into two approximately equal portions. 
 Grind a cake of fresh, compressed yeast with 20 c.c. of water, 
 filter the liquid and add one-half the filtrate to each of the su- 
 crose solutions. To one of the solutions also add a few drops of 
 a strong alcoholic solution of thymol, and a drop of acetic acid. 
 Place both solutions in flasks and keep them for twenty-four hours 
 at a temperature between 35 to 40. The flasks may be loosely 
 stopped with a little cotton wool or by covering with watch-glasses. 
 They should not be tightly stopped. The solution containing the 
 thymol will be converted into invert-sugar without fermentation; 
 the other solution will soon begin to ferment, give off carbon dioxide 
 and form alcohol. Both solutions will acquire levorotatory power. 
 
 Experiment 39. Make a solution of sucrose containing about 
 5 grams in 100 c.c.; add i gram of citric acid and boil the liquid 
 for ten minutes, replacing the water as it is lost. Allow the solu- 
 tion to cool and examine it for invert-sugar by any of the standard 
 tests, such as reduction of Fehling's solution, reduction of bismuth 
 subnitrate, formation of osazone by phenylhydrazin or rotatory 
 power. 
 
112 ORGANIC CHEMISTRY. 
 
 GLUCOSIDES. 
 
 This term includes a large number of substances, mostly 
 of vegetable origin, that are easily decomposed into several 
 simpler bodies, one of which is dextrose or an analogous 
 carbohydrate. Dilute acids and some enzyms are the 
 usual means of producing these changes, the action is, 
 in most cases, by hydrolysis. A glucoside may, therefore, 
 be regarded as an 'ester of the carbohydrate yielded by it. 
 
 Most glucosides are non-nitrogenous. Many are the 
 active principles of the plants in which they occur, but in 
 some cases this activity is due to the products of decom- 
 position and not to the glucoside itself. This is the case 
 with mustard, bitter almonds and wild cherry bark. As 
 a rule, the glucosides are associated with the enzym 
 necessary for their decomposition. Starch and some of the 
 other carbohydrates may be regarded as glucosides as they 
 yield dextrose by hydrolysis. 
 
 Amygdalin, C 2Q R 27 ^O 11J exists in tissues, especially seeds, 
 of many plants of the order Rosaceae, in association with an 
 enzym called synaptase. This acts on the amygdalin, 
 when the seeds are crushed in cold water; but boiling 
 alcohol coagulates the synaptase and dissolves the unde- 
 composed amygdalin. The latter is a white, crystalline 
 body, soluble in alcohol and water, but not in ether. The 
 decomposition to which it is susceptible is explained in 
 connection with the description of hydrogen cyanide. 
 
 Salicin, C 13 H 18 O 7 , is found principally in the bark and 
 leaves of the poplar and willow. It crystallises in white 
 needles; insoluble in ether, but soluble in water and alco- 
 hol. Salicin decomposes as follows: 
 
 C 13 H 18 7 + H 2 C 7 H 8 2 + C 6 H 12 C 
 C 7 H 8 O 2 is called saligenin. 
 
GLUCOSIDES. 113 
 
 The structural formula of salicin shows open and closed 
 chains. The significance of the hexagon is explained under 
 Benzene. The structure of dextrose is also evident, and 
 a methyl ether group (H 3 C O) is present. 
 
 I 
 
 C 
 
 H HH 
 
 v 
 
 C O H 
 
 H H H H 
 
 fill 
 
 
 H 3 C O^ ) 00000 
 ^ ' 
 
 I I I I 
 CC C C C H 
 
 ill 
 H H H H 
 
 Tannins. These are astringent principles, widely dif- 
 fused in the vegetable kingdom. They dissolve in water 
 and have an acid reaction; hence are often called tannic 
 acids. Many forms are known; they possess the common 
 property of precipitating gelatin and giving dark-colored 
 precipitates with ferric salts. Their action on gelatin 
 is utilised in the preparation of leather, and their action 
 with ferric salts in making ink. 
 
 Ordinary tannin, gallo-tannic acid, occurs in nutgalls 
 excrescences formed on a species of oak by puncture by an 
 insect and sumach. It is usually seen as a loose, brittle, 
 light-yellow, non-crystalline mass, very soluble in water 
 and highly astringent. It gives a bluish-black precipitate 
 with ferric salts. The common form is not entirely a 
 glucoside but contains a large amount of digallic acid, 
 C 14 H 10 O 9 . 
 
 When tannin is boiled with dilute acids, or mixed with 
 water and exposed to moist air, it forms gallic acid by 
 hydrolysis of the glucoside or digallic acid. 
 
114 ORGANIC CHEMISTRY. 
 
 Thus : 
 
 Tannin (glucoside). Dextrose. Gallic acid. 
 
 C 27 H 22 17 + 4 H 2 = C 6 H 12 6 + 3C 7 H 6 5 . 
 
 Digallic acid. Gallic acid. 
 
 C 14 H 10 9 + H 2 . 2C 7 H 6 5 . 
 
 The formation of gallic acid is a loss in the manufacture 
 of leather, since it has no tanning qualities. The change 
 can be prevented by antiseptic substances, such as sulphur- 
 ous and boric acids, and solutions of these are sold under 
 the name of .antigalline. The process of tanning consists 
 essentially in the tannin rendering the gelatinous matter of 
 the hide insoluble, and therefore not liable to decomposi- 
 tion. 
 
 Sinigrin, Potassium Myronate, KC 18 H 10 NS 2 O 10 . The 
 seed of the black mustard contains this body and also 
 an enzym, myrosin, which decomposes the sinigrin accord- 
 ing to the following equation : 
 
 KC 10 H 18 NS 2 10 == C 3 H 5 CNS + C 6 H 12 O 6 + KHSO 4 . 
 
 C 3 H 5 CNS is allyl thiocyanate, to which the irritating 
 action of mustard is due. Preparations of it should not be 
 made with hot water as this will injure the enzym and 
 prevent the decomposition. It will be noted that this is 
 not hydrolysis. By direct action of amine, allyl thiocya- 
 nate is converted into thiosinamin (allyl thiocarbamide). 
 
 White mustard seed contains a glucoside, sinalbin, and 
 an enzym, myrosin. 
 
 Indican, C 52 H 62 O 34 , occurs in several plants, especially 
 those of the genus Indigofera. By boiling with acids it 
 yields the color known as indigo blue (indigotin). Indigo 
 blue is obtained from the plants containing indican, 
 by macerating them with water, and exposing to the air 
 until fermentation occurs and blue is deposited. 
 
Cyclic Hydrocarbons. 
 
 In these compounds, carbon atoms are connected into 
 one or more closed series or chains. Three is the smallest 
 number of atoms that can form, such a chain. When the 
 chain is composed of one kind of atoms, the molecule is 
 honiocyclic or isocyclic. This term is generally applied to 
 carbon chains, although obviously not necessarily so 
 limited. The nucleus of three nitrogen atoms in azoimide 
 is homocyclic. As with the open-chain compounds, 
 some of the valencies may be latent, that is, two atoms 
 may be connected by more than one bond. These latent 
 valencies are developed only under special conditions, 
 giving origin to additive compounds. 
 
 When the chain includes atoms of different elements, it 
 is termed keterocyclic . The more important instances of 
 this arrangement are rings containing two or more carbon 
 atoms linked with an atom of oxygen, sulphur or nitrogen. 
 
 These closed-chain compounds may have the same 
 empirical formula as open-chain compounds. The former 
 are, therefore, not infrequently named by attaching the 
 prefix "c'yclo" to the name of the open-chain compounds. 
 Thus, trimethene (CH 2 ) 3 , isomeric with C 3 H 6 , propane, 
 is called ''cyclopropane." 
 
 HOMOCYCLIC COMPOUNDS. 
 
 Of all these series, the most important and interesting, 
 both from practical and theoretic points of view, is the six- 
 
Il6 ORGANIC CHEMISTRY. 
 
 carbon homocyclic series, commonly termed the Benzenes, 
 from the name of the fundamental hydrocarbon. It will 
 be sufficient to note a few points in regard to other groups. 
 Three-membered Rings. An instance of this is found in 
 cyclopropane, trimethylene or trimethene, isomeric with 
 propane, the difference in structure being shown in the 
 annexed formulas: 
 
 H H H 
 
 I I I H 2 C 
 
 H C C C H | >CH 2 
 
 i A A 
 
 Propane Cyclopropane 
 
 Four -member ed Rings. The compounds of this type 
 have as yet but little practical interest. Methyl tetrame- 
 thene, i (CH 2 ) 3 CH(CH 3 ), is an instance. 
 
 Five -member ed Rings. A considerable number of deri- 
 vatives of this type are known. Common camphor yields 
 methene derivatives of this type, but the reactions by 
 which these are produced are not yet known. 
 
 Seven-membered rings are also known but they tend to 
 reduce to six-carbon rings. 
 
 SIX-CARBON HOMOCYCLIC COMPOUNDS. 
 
 Three subgroups of these are distinguished: 
 
 Benzenes (aromatic hydrocarbons). 
 Terpenes (essential oils). 
 Polynucleated compounds. 
 
 BENZENES. 
 
 Historical Note. In the manufacture of illuminating-gas by 
 the destructive distillation of bituminous coal and shale and in 
 
COLLEGE 
 
 of PHARMACY 
 
 BENZENES. 117 
 
 the manufacture of coke, many products are obtained, some gaseous 
 at ordinary temperatures, others liquid and solid. The liquid and 
 solid bodies are collected in mixture as a dark, thick liquid, with 
 an odor recalling that of the gas. This is known as coal-tar. For 
 a long while it was a useless by-product and its disposal a serious 
 problem. In 1825 Faraday obtained, by compressing coal gas, a 
 hydrocarbon, which is now known to be identical with that ob- 
 tained by Mitscherlich in 1834, by distilling calcium benzoate, 
 which, on account of this source, was called "benzene." In 1845 
 Hofmann discovered the same body in coal-tar, and not long after- 
 wards, Mansfield, a pupil of Hofmann, prepared it in practicable 
 quantity from the tar. Mansfield lost his life while preparing a 
 sample for public exhibition. 
 
 Experiments with benzene soon showed that it is 
 capable of yielding many derivatives, and while showing 
 no isomeric modifications itself, its derivatives show many 
 instances thereof. The chemical nature of benzene was 
 imperfectly understood up to 1865, when Kekul6 suggested 
 that its molecule consists of six carbon atoms in a closed 
 chain with six latent valencies and six other valencies 
 satisfied by hydrogen. By this theory, so far, all the 
 numerous derivatives can be formulated consistent with 
 their isomerisms and relations. Moreover, the properties 
 of benzene itself are explained by the theory. Benzene 
 ordinarily exhibits the functions of a saturated hydrocar- 
 bon, but, under special conditions, it is capable of forming 
 additive compounds, this addition taking place by the 
 simultaneous action of two valencies. 
 
 Kekule's view has been generally accepted, and ex- 
 tended to many other classes of compounds. Some 
 difference of opinion exists as to the manner in which the 
 latent valencies are disposed, but it is not necessary to 
 discuss this point. 
 
 Coal-tar contains many substances that are structurally 
 related to benzene; these may be separated, but usually 
 
Il8 ORGANIC CHEMISTRY. 
 
 somewhat imperfectly by fractional distillation. It is 
 known that benzene obtained from tar, unless especially 
 purified, contains a compound in which sulphur takes the 
 place of two carbon atoms. This will be noted under the 
 heterocyclic compounds. Among the important bodies 
 associated with benzene in coal-tar, are toluene, phenol, 
 anthracene, naphthalene and pyridin. The benzene oc- 
 curs in the most volatile portion of the tar, termed light 
 oils. Crude benzene is known in commerce as "benzol," 
 a name which has, unfortunately, been much used for ben- 
 zene itself. 
 
 Benzene, phene, C 6 H 6 , is a colorless mobile, volatile 
 liquid with an odor that suggests coal-tar. It melts at 
 5.4 and boils at 80.4. The solid benzene resembles 
 common paraffin. The sp. gr. of the liquid is 0.8.99. It 
 has high solvent powers for many substances, notably fats, 
 waxes and resins. It is readily inflammable, burning with 
 a smoky flame, but does not undergo direct oxidation by 
 ordinary oxidising agents. Benzene, as already noted, 
 forms two classes of derivatives, additive and substitutive. 
 The former are of little practical interest, but the latter are 
 very numerous and important. Additive compounds of 
 monad elements are formed with even numbers of atoms, 
 e. g., benzene chlorides are C 6 H 6 C1 2 ; C 6 H 6 C1 4 ; C 6 H 6 C1 6 . 
 The substitution of monad elements or radicles may take 
 place singly, chlorbenzenes, C 6 H 5 C1; C 6 H 4 C1 2 ; C 6 H 3 C1 3 ; 
 C 6 H 2 C1 4 ; C 6 HC1 5 ; C 6 C1 6 , being known. 
 
 It is necessary to distinguish clearly between these two 
 classes of derivatives. The nomenclature used is exemplified 
 above. Additive compounds are named in the same 
 manner as the binary compounds of inorganic chemistry 
 (compare benzene dichloride, C 6 H 6 C1 2 , with zinc dichlo- 
 ride, ZnCl 2 ). Substitution compounds are named by at- 
 
BENZENES. Iig 
 
 taching to the fundamental name syllables indicating 
 the nature of the substituting bodies and also numerical 
 syllables; thus, C 6 H 4 C1 2 is dichlorbenzene . 
 
 The assumed structure of the molecule of benzene is 
 shown in the following diagrams of the carbon nucleus 
 the carbon atoms represented by dots and arrangement 
 of valencies. Several diagrams are given, showing sug- 
 gestions as to manner and disposition of the latent valen- 
 cies. 
 
 I- 
 
 Kekule 
 
 
 
 i 
 
 Armstrong 
 
 Ladenburg's prism 
 
 Carbon atoms in benzene (various suggestions) 
 
 Ladenburg's prism modified 
 
 Benzene derivatives obtained by substituting the hydro- 
 gen by equivalent atoms or groups are numerous and show 
 many instances of isomerism. These are best explained 
 by tridimensional (stereo-chemic) formulas but such a 
 
I2O ORGANIC CHEMISTRY. 
 
 method is not here available and the ordinary structural 
 formulas must suffice. 
 
 The following compounds illustrate these substitutions 
 and the nomenclature of them : 
 
 C 6 H 5 C1 chlorbenzene. 
 
 C 6 H 4 C1 2 dichlorbenzene. 
 
 C 6 H 3 (HO) 3 trihydroxybenzene. 
 
 C 6 H 4 (COOH)(HO) carboxyhydroxybenzene. 
 
 For convenience in naming compounds, C 6 H 5 , is fre- 
 quently called phenyl, and C 6 H 4 , phenylene. 
 
 The term "hydroxy " in these names is often abbreviated 
 to "oxy." Thus, C 6 H 5 HO is called oxybenzene. The 
 conditions of symmetry in benzene are such that no isomer- 
 ism is to be expected (and none has been observed) in 
 the compounds formed by a single substitution of the 
 hydrogen. Hence, phenol, hydroxybenzene, is identical 
 in nature no matter how prepared. When two or more 
 hydrogen atoms are replaced, isomerism at once becomes 
 possible, and instances become very numerous when 
 several different substituting molecules are introduced. 
 To aid in expressing the formulas of these isomeric bodies, 
 and also in distinguishing them by name, the normal 
 benzene-molecule is represented by a hexagon which, 
 when unmodified, stands for C 6 H 6 ; it is termed a "ring- 
 symbol." A symbol or formula at any angle of this 
 hexagon indicates that an atom of hydrogen is replaced by 
 the body represented by that symbol or formula. The 
 annexed diagrams will show the detailed structural for- 
 mula and ring-symbol. The carbon atoms are here again 
 represented by dots. X represents any monad elements 
 or radicle. 
 
BENZENES. 121 
 
 X 
 
 I 
 
 -H 
 
 I 
 H 
 
 Substitution compound and ring symbol 
 
 The position of the substituting body is immaterial in 
 this case, but it is usually placed at the upper angle. 
 When two hydrogen atoms are replaced three isomeric 
 bodies will be formed, whether the replacement is by the 
 same or different bodies. To assist in indicating, the angles 
 are distinguished by numbers in the order of those on a 
 clock, thus: 
 
 4 
 
 Substitution of two hydrogen-atoms are shown in the 
 annexed ring-symbols. 
 
 XXX 
 
122 ORGANIC CHEMISTRY. 
 
 X, as before, represents any monad element or radicle. 
 It will be seen that 1-5 and 1-6 are identical, respectively, 
 with 1-3 and 1-2, so that three and only three isomeric 
 forms are to be expected. This accords with all known 
 facts. Moreover, the rule applies to cases in which two 
 different substituting molecules appear. The numerical 
 nomenclature is not generally used in these instances, 
 the compounds being designated by prefixing the following 
 syllables : 
 
 ortho for 1-2 
 
 meta for 1-3 
 
 para for 1-4 
 
 Substitutions of three hydrogen atoms by three atoms 
 or molecules of the same kind give rise to three isomeric 
 forms which are exemplified in the annexed formulas of 
 the three trichlorbenzenes together with distinctions by 
 the two systems of nomenclature in vogue. 
 
 1-2-3 i- 2 -4 1-3-5 
 
 Consecutive Unsymmetric Symmetric 
 
 or adjacent 
 
 If the three substituting bodies are not identical, the 
 isomerism becomes complex, and substitutions of four 
 or five hydrogens still more so, but substitution of six 
 hydrogens by identical bodies gives only one form. The 
 latter point is exemplified in the annexed formula: 
 
BENZENES. 123 
 
 COOH 
 
 HOOC|/\COOH 
 HOOcl JcOOH 
 
 COOH 
 
 Mellitic acid, hexacarboxybenzene. 
 
 No uniform, system is available for representing additive 
 compounds by ring-symbols. A provisional method is 
 adopted in this book for the few instances in which such 
 representation is required. Additive elements or groups 
 are indicated by placing the proper sign at a short dis- 
 tance from the angle and connected by a bond. There is 
 also no uniform method of indicating cyclic combinations 
 containing less than six carbon atoms nor those containing 
 atoms of different elements (heterocyclic). Some chemists 
 use a truncated hexagon for five-membered rings. For 
 indicating the heterocyclic (pyridin) ring, C 5 H 5 N, the 
 benzene hexagon with a small N close to an angle will be 
 used in this book. Both these methods are exemplified in 
 the formula for pyridin hydride. 
 
 For illustration and comparison, the ring-symbols of a 
 few compounds are given here. The substances are 
 described in the following pages. 
 
 HO N0 9 COOH 
 
 Hydroxybeazene Nitrobenzene Carboxybenzene 
 
 (Phenol) (Benzoic acid) 
 
124 ORGANIC CHEMISTRY. 
 
 HCO CH 2 HO HO 
 
 0" 
 
 Benzaldehyde Benzyl alcohol Resorcinol 
 
 (Bitter-almond oil) 
 
 COOH 
 
 HCO 
 
 HCO 
 
 HO 
 
 Salicylic acid 
 
 CH 
 
 'HO 
 
 OCH 3 
 
 )CH 3 
 
 Isovanillin 
 
 NH, 
 
 Picric acid 
 
 HS0 3 
 
 Sulphanilic acid 
 
 1-4 Amidobenzene- 
 
 sulphonic acid 
 
 HOMOLOGUES AND DERIVATIVES OF BENZENE. Ben- 
 
 zene is the first member of a series of the general formula 
 C n H 2n _ 6 of which the following compounds are examples: 
 
 methylbenzene 
 dimethylbenzene 
 trimethylbenzene 
 tetramethylbenzene 
 
 Toluene is a colorless liquid, of sp. gr. 0.870. It boils 
 at 110. A substitution of one atom of the benzene- 
 hydrogen of toluene must produce three isomeric forms, 
 
 Benzene, 
 
 C,H 6 
 
 
 Toluene, 
 
 C 7 H 8 
 
 C 6 H 5 (CH 3 ), 
 
 Xylene, 
 
 C 8 H 10 
 
 C 6 H 4 (CH 3 ) 2 , 
 
 Cumene, 
 
 C 9 H 12 
 
 C 6 H 3 (CH 3 ) 3 , 
 
 Cymene, 
 
 Ci H 14 
 
 C 6 H 2 (CH 3 ) 4 , 
 
BENZENES. 125 
 
 since the substituting group must take a position either 
 j-2 (ortho), 1-3 (meta), or 1-4 (para), with reference to the 
 methyl group, for, as the structural formula and syste- 
 matic name of toluene indicates, it is not a seven-carbon 
 chain but a substitution of methyl for one of the hydrogen 
 atoms of benzene. It is obvious, however, that the sub- 
 stitution may take place in the methyl group. This, 
 which is termed " side '-chain" substitution, gives rise to 
 bodies which show, in empirical formulas, isomerisms with 
 the ordinary benzene substitutions. This phenomenon of 
 side-chain substitution is now receiving special attention 
 
 CH 
 
 Methyl-benzene 
 (Toluene) 
 
 in pathological chemistry, and in connection with theories 
 of immunity, but the subject is still imperfectly developed 
 and is too complex for more than mention here. 
 
 H ydroxytoluene , C 6 H 4 (HO)(CH 3 ), of which there are three 
 forms is isomeric but not identical with C 6 H 5 CH 2 HO. The 
 latter might be called hydroxymethylbenzene for dis- 
 tinction. It is, however, known as benzyl alcohol and is 
 considered to be the true alcohol of this formula. 
 
 Nitrobenzene, C 6 H 5 NO 2 . This is easily prepared by the 
 action of strong nitric acid on benzene. It is a colorless 
 liquid, with an odor somewhat like that of essential oil 
 of bitter almonds, for which it has been used as a sub- 
 stitute in flavoring soaps and cosmetics. It is known 
 
126 ORGANIC CHEMISTRY. 
 
 commercially as oil of myrbane. The reaction for its 
 production is: 
 
 C 6 H 6 + HNO 3 == C 6 H 5 NO 2 + H 2 O 
 
 Aniline, Phenylamine, Amidobenzene , C 6 H 5 NH 2 . This 
 is made by the action of nascent hydrogen on nitroben- 
 zene, e. g., by mixing nitrobenzene with tin and hydro- 
 chloric acid or with iron filings and acetic acid. The re- 
 action is : 
 
 C 6 H 5 N0 2 + H 6 == C 6 H 5 NH 2 + 2 H 2 O 
 
 Aniline is a liquid, boiling at 182. It is an active 
 poison. By the action of oxidising agents it becomes 
 converted into bodies of complicated composition, some 
 of them having coloring powers of great beauty and 
 variety, so-called "aniline or coal-tar colors." Crude 
 aniline, commonly known as "aniline oil," contains homol- 
 ogous substances, such as toluidines (methyl anilines) and 
 xylidines (dimethyl anilines). 
 
 Phenol, Hydroxybenzene , C 6 H 5 HO, Carbolic acid, Phenic 
 acid, Phenylic acid. This exists in coal-tar, and can 
 be made artificially by several processes. It forms color- 
 less crystals, deliquescent, and soluble in water, melting 
 at 34 and boiling at 187. It has an odor like that of 
 kreasote. It is sometimes called "coal-tar kreasote." 
 The commercial article usually has a pink tinge. Applied 
 to mucous membranes, phenol promptly produces blanch- 
 ing and then an eschar. Strong alcohol is antidotal in 
 action. The hydrogen in the hydroxyl of phenol can 
 easily be replaced by positives yielding a series of com- 
 pounds termed "phenates" or "phenylates." The sodium 
 compound being readily soluble in water and less corrosive 
 than phenol, is used as an antiseptic and as a wash for 
 removing skin-parasites from domestic animals. 
 
BENZENES. 127 
 
 Benzaldekyde, C 6 H 5 HCO, is oil of bitter almonds. Its 
 formation from amygdalin by a species of fermentation 
 is pointed out elsewhere. It is a colorless liquid, heavier 
 than water, and, as usually made, has the smell of hy- 
 drogen cyanide, since that body is formed from amygdalin 
 at the same time as the benzaldehyde. Oil of bitter 
 almonds has been used in confectionery as a flavor. It is 
 sometimes substituted by nitrobenzene. 
 
 Benzole acid, carboxybenzene, C 6 H 5 COOH, occurs in 
 various resins, especially in benzoin, and can be made 
 artificially by several methods. The usual method is 
 by oxidation of toluene; another is from hippuric acid. 
 Benzoic acid is a white crystalline solid, with faint odor 
 and disagreeable taste. It dissolves but sftghtly in cold 
 water, but more so in hot water and alcohol. It sublimes 
 at a temperature below its boiling point. It is an antisep- 
 tic. 
 
 Sodium benzoate is a white crystalline solid with faint 
 odor. It is soluble in water; the solution has a somewhat 
 nauseous taste. It has marked antizymotic properties 
 and is now used as a preservative in foods liable to ferment. 
 
 Benzyl alcohol, Phenyl carbinol, C 6 H 5 (CH 2 HO), is of little 
 practical importance, but is interesting because it is the 
 true alcohol of this series. It is isomeric with the hydroxy- 
 toluenes (cresols) but entirely of a different nature and 
 quite different in properties. 
 
 Benzyl alcohol 
 
 Resorcinol, Resorcin, Metadihydroxybenzene, C 6 H 4 (HO) 2 
 
128 ORGANIC CHEMISTRY. 
 
 (for structural formula see p. 124). This can be obtained 
 from the resins of galbanum and asafetida and also synthet- 
 ically from several benzene derivatives. It is a colorless, 
 crystalline body soluble in water, alcohol and ether. It 
 is antiseptic. 
 
 Pyrogallol, Pyro gallic acid, C 6 H 3 (HO) 3 , 1-2-3 trihydroxy- 
 benzene, was originally obtained, as its name indicates, by 
 heating gallic acid. It is a colorless, crystalline body, 
 soluble in water. It absorbs oxygen from the air and 
 decomposes. The action is especially rapid in alkaline 
 solution and is utilised in developing photographic nega- 
 tives and in the analysis of gaseous mixtures containing 
 free oxygen. 
 
 HO 
 
 Pyrogallol 
 
 Phloroglucol, Phloroglucin, C 6 H 3 (HO) 3 . The molecule 
 of this body is supposed to be tautomeric. The annexed 
 formulas show two possible forms. One form is 1-3-5 
 trihydroxybenzene, the other form is triketohexamethene. 
 
 HO 
 
 Hol JHO 
 
 Originally obtained from a glucoside, phloridzin, of certain 
 root -barks, it is now made from resorcinol. It is a color- 
 
BENZENES. I2Q 
 
 less, crystalline body, soluble in water and alcohol. The 
 alcoholic solution is used in mixture with a solution of 
 vanillin for detection of hydrochloric acid in gastric juice. 
 A solution of phloroglucol and dilute hydrochloric acid is 
 used for detecting some forms of woody tissue. When 
 the solution is added to materials containing these tissues, 
 a bright red stain is produced. This reaction depends 
 upon the existence of substances somewhat similar to 
 vanillin. A solution of phloroglucol in dilute sodium 
 hydroxide is used as a test for formaldehyde. 
 
 Phenolsulphonic acids, C 6 H 4 (HO)(HSO 3 ). Three of these 
 are possible; all are known, but only 1-2 and 1-4 can be 
 obtained by the direct action of phenol upon sulphuric acid. 
 The first form tends to pass into the 1-4 form, slowly when 
 cold, rapidly when hot. These acids are capable of form- 
 ing salts which are strongly antiseptic and have been used 
 as disinfectants. 
 
 Phenylsulphuric acid, Phenyl acid sulphate, C 6 H 5 HSO 4 , 
 is empirically isomeric with the phenolsulphonic acids but 
 quite different in structure. Its potassium salt occurs in 
 urine, and is one of the so-called ethereal sulphates the 
 formation of which is supposed to be dependent on the 
 putrefactive processes taking place in the intestinal canal. 
 
 The structural formulas will show the relations of the 
 four bodies. 
 
 HO HO 
 
 HSO, 
 
 HSO 3 
 
 Phenolsulphonic acids Phenylsulphuric acid 
 
 Thymol (see structural formula p. 124), isopropylmeta- 
 
130 ORGANIC CHEMISTRY. 
 
 hydroxy toluene, is one of the ingredients of oil of thyme, 
 and can be prepared synthetically. It forms colorless 
 crystals that melt at 50. It has an odor recalling 
 that of the oil of thyme. An isomeric form is known 
 called carvacroL Thymol has marked antiseptic powers. 
 Its odor prevents its use as a food-preservative. Its 
 principal medical use is as a vermifuge in the treatment of 
 uncinariasis > a disease due to the presence of minute 
 worms in the intestinal canal. 
 
 mmzo?/,i-2hydroxymethoxybenzene, C 6 H 4 (HO)(CH 3 O), 
 is a mixed ether of phenyl and methyl with rlcoholic 
 hydroxyl also present. It is the important constituent 
 of kreasote from beechwood tar. When pure it is a white 
 solid with but slight irritating qualities. Commercial 
 guaiacol is a liquid, often very impure, and decidedly 
 irritating to mucous membranes. By treatment with 
 carbonyl chloride, COC1 2 , a derivative having the formula 
 (C 6 H 4 OCH 3 ) 2 C0 3 is obtained. It has been used as a thera- 
 peutic agent under the name guaiacol carbonate. 
 
 Vanillin methylprotocatechuic aldehyde see p. 124) is 
 the principal flavoring constituent of vanilla, which con- 
 tains from i to 2 per cent. It is now made artificially 
 from eugenol. It forms colorless, needle-like crystals, 
 with the well-known agreeable odor. It is freely soluble 
 in alcohol, but not very soluble in water. 
 
 Picric acid, C 6 H 2 (NO 2 ) 3 HO, is the trinitro phenol in which 
 the nitro-groups are arranged symmetrically with regard 
 to each other and to the hydroxyl. The other forms 
 are but little known. Picric acid is obtained by the 
 oxidation of indigo, silk, wool and leather, and syntheti- 
 cally by the oxidation of phenol. Phenolsulphonic acids 
 mixed with nitrates produce some picric acid, but several 
 lower nitrophenols are also formed. Picric acid may be 
 
BENZENES. 131 
 
 produced by the direct oxidation of phenol with nitric 
 acid, but the action is apt to be violent. Picric acid is a 
 deep yellow solid, soluble in water. It dyes silk and wool 
 without a mordant. It coagulates albumin. It is very 
 bitter, a property to which the name refers. With care 
 it can be sublimed without decomposition, but under 
 some conditions explodes with great violence. The high 
 explosive called "lyddite" is picric acid. As the formula 
 shows, it is not a carboxyl acid, but the nitro-groups give 
 the hydrogen of the hydroxyl acid function. This hydro- 
 gen may be replaced by positives, forming salts, most of 
 which are explosive. 
 
 Salicylic acid, orthohydroxycarboxybenzene, oxybenzoic 
 acid, C 6 H 4 (COOH)(HO) (see p. 124), differs in formula 
 from benzoic acid by an additional atom of oxygen, hence 
 the name oxybenzoic acid. It is usually made from sodium 
 salicylate obtained by the action of carbon dioxide on 
 sodium phenate. 
 
 Sodium phenate. Sodium salicylate. 
 
 NaC 6 H 5 O + CO 2 = NaC 7 H 5 6 3 
 
 Salicylic acid forms colorless prismatic crystals, sparingly 
 soluble in water. The solution gives a deep violet color 
 with ferric salts. It has high antiseptic qualities and is 
 much used as a preservative in foods and beverages. 
 Its methyl ester exists in the volatile oils of wintergreen, 
 (Gaultheria procumbens) and birch (Betula lento). By 
 saponifying these, the natural acid can be obtained; this 
 is preferable for therapeutic use on account of its freedom 
 from the dangerous by-products occasionally present in 
 the acid made from phenol. Salicylic acid has a marked 
 restraining action on several starch-converting enzyms. 
 
132 ORGANIC CHEMISTRY. 
 
 Cresols, C 6 H 4 (CH 3 )HO, methyl phenols, cresylic acids. 
 These have the same relation to toluene, C 7 H 8 , that phenol 
 has to benzene. Phenol is hydroxybenzene ; cresol is hy- 
 droxytoluene. They exist in coal-tar. Three isomeric forms 
 are known. They are often present in commercial phenol. 
 
 Lysol, now much used as a surgical antiseptic, is a mix- 
 ture of the cresols saponifed by caustic soda and thus 
 rendered soluble in water. 
 
 Eugenol, allyl guaiacol, C 6 H 3 (C 3 H 5 )(OCH 3 )(OH). This 
 forms the greater portion of oil of cloves, and occurs in 
 other essential oils. It differs from vanillin in containing 
 the monad allyl radicle, C 3 H 5 , in place of the aldehyde 
 group HCO. By oxidation allyl may be converted into 
 HCO, and vanillin obtained. This is now the commercial 
 source of synthetic vanillin. 
 
 Piperonal. The structural formula shows this to be an 
 aldehyde-ether. It bears some relation to vanillin and 
 benzaldehyde. It is a liquid of pleasant odor. . 
 
 HCO 
 
BENZENES. 133 
 
 QUINONES. The substitution of oxygen for hydrogen in 
 the proportion of O 2 for H 2 in closed-chain compounds, 
 gives rise to a series of bodies termed quinones. Some of 
 them are analogous in structure to hydrogen dioxide, and 
 like it are active oxidising agents. Two series have been 
 obtained, representative of 1-2 and 1-4 substitutions. 
 The latter series true, or paraquinones, are of the greater 
 importance. Some of them are probably tautomeric, 
 oscillating between a peroxide and a ke tonic structure. 
 In the latter condition they have reducing power. 
 
 The structural formulas of these forms is illustrated 
 by benzoquinone : 
 
 Benzoquinone 
 
 Peroxide form Ketonic form 
 
 C.H 4 S C 4 H 4 (CO) 2 
 
 Quinone, benzoquinone, the type substance, may be pre- 
 pared in many ways. The usual method is by oxidising 
 aniline with chromic acid. It forms yellow crystals which 
 have a penetrating disagreeable odor and irritate the 
 skin. 
 
 Phthalic acids , dicarboxybenzenes, C 6 H 4 (COOH) 2 . These 
 are the final products of the oxidation of side-chains of 
 benzene derivatives and their preparation is, therefore, 
 valuable as a means of ascertaining the position of these 
 chains, since the forms of acid yielded will be dependent 
 on the position of molecules oxidised. There are, of 
 course, three forms of these acids: 1-2, 1-3, 1-4. The 
 
134 ORGANIC CHEMISTRY. 
 
 methods used depend upon the form of the acid desired. 
 The most important is: 
 
 Phthalic acid, C 6 H 4 (COOH) 1 (COOH) 2 , 1-2 dicarboxyben- 
 zene. This is obtained by the oxidation of naphthalene, 
 by which the extra ring is broken and its carbon con- 
 verted in carboxyl. It is a colorless, crystalline body 
 soluble in water. It is prepared in large quantity for 
 the manufacture of commercial synthetic products. Its 
 preparation from naphthalene is the first step in the 
 manufacture of artificial indigo-blue. 
 
 Saccharin, Benzosulphinide , C 7 H 5 NSO 3 . The struc- 
 tural formula shows the nature of this body. It is an 
 imido-derivative of benzosulphonic acid. It is a white 
 crystalline solid soluble in water; the solution is very 
 sweet. Saccharin has been estimated as several hundred 
 times as sweet as cane sugar. It has marked antiseptic 
 powers, and is much used as a substitute for sugar and 
 sometimes as a preservative. 
 
 Saccharin 
 
 The following formulas show several benzene derivatives, 
 some of which do not need special description : 
 
 HCO 
 
 HO 
 HO 
 
 Phenazine Protocatechuic aldehyde 
 
BENZENES. 135 
 
 Phenylether 
 
 PHTHALEINS. These are complex derivatives of phthalic 
 acid. Some of them have acquired much importance 
 on account of their value as dyes and indicators, and one of 
 them, fluorescein, on account of its optical properties. 
 The general nature of the structural formula is shown by 
 that for phenolphthalein given below. The phthaleins must 
 not be confounded with the "'pktkalins',' 9 a less important 
 group, not requiring special consideration here. 
 
 Phenol phthalein is a light yellow powder almost in- 
 soluble in water but freely soluble in alcohol. The solution 
 is nearly colorless when neutral or acid, but becomes bright 
 red when alkaline. It is much used as an indicator. 
 
 HO 
 
 OYO 
 
 H( 
 
 \ / 
 
 O C 
 
 II 
 O 
 
 Phenol phthalein 
 
 Resorcinolphthalein, fluorescein, is a reddish powder 
 which dissolves in strong alkaline solutions to produce a 
 dark-red solution, but when highly diluted the liquid 
 
136 ORGANIC CHEMISTRY. 
 
 shows a vivid green fluorescence. The coloring power of 
 fluorescein is so great that large bodies of water may be 
 made distinctly fluorescent by moderate quantities of the 
 material, and it has been used for tracing underground 
 connections between streams and springs. 
 
 EOSINS, RHODAMINS. These classes of colors, now 
 well-known on account of their use in coloring foods, 
 beverages and confections, are derivatives of the phtha- 
 leins. The cosins are bright red dyes; most of them are 
 fluorescent. Eosin proper is tetrabromofluorescein, and 
 erythrosin, tetraiodofluorescein. The rhodamins are the 
 phthalein derivatives of 1-3 amidophenol; they are also 
 brilliant dyes of different shades of red and fluorescent. 
 
 Indol, C 8 H 7 N. According to the system of nomencla- 
 ture now generally used, this body should be termed 
 "in din." The structural formula shows it to be a union 
 of a pyrrol ring with a benzene ring. It is of considerable 
 importance because of its occurrence among the products 
 of putrefaction, and pancreatic digestion of proteids, 
 and also its relation to the principal coloring matter of 
 indigo. 
 
 Skatol is a methyl substitution of indol. It occurs with 
 indol and is a characteristic ingredient of the contents of 
 the intestinal canal. 
 
 =C CH 3 
 
 Indol (Indin) Skatol (Skatin) 
 
 (Methyl indin) 
 
 Indigotin, C 16 H 10 N 2 O 2 , the principal coloring matter 
 of indigo, is a duplicated indol with substitution of two 
 
BENZENES 137 
 
 oxygen atoms for four hydrogen atoms. It exists in the 
 indigo plant in the form of a glucoside, "indican," which 
 is hydrolysed by dilute acids or by enzyms. The change 
 can be brought about by exposing the macerated plant- 
 tissues to air. Indigotin is insoluble in water. It is of a 
 bright blue color, and in masses has a copper lustre. 
 Natural indigotin is contaminated with other coloring 
 matters. To render indigo available for dyeing it is 
 made soluble, either by converting it into a sulphonic acid 
 or into indigo-white, a compound containing two ad- 
 ditional hydrogen atoms obtained by fermentation methods, 
 The sulphonic acid dyes directly; the indigo-white is 
 soluble and impregnates the fibre and when exposed to 
 the air reverts to indigotin and becomes blue and in- 
 soluble. 
 
 The synthesis of indigotin has been accomplished in 
 several ways: The following method, now employed on a 
 practical scale, illustrates the general methods of organic 
 synthesis. 
 
 Naphthalene from coal-tar is converted into phthalic 
 acid, C 6 H 4 (COOH) 2 this phthalimide, C 6 H 4 (CO) 2 NH, 
 this into anthranilic acid, C 6 H 4 (COOH)(NH 2 ), this into 
 a body of the formula C 6 H 4 (COOH)(NH)(CH)(COOH), 
 which is then converted into indoxylcarboxylic acid, 
 C 6 H 4 (CO)(NH)(CHCOOH), from which indigotin is ob- 
 tained. 
 
 Experiment 40. Make an intimate mixture of benzoic acid with 
 twice its weight of quicklime, and heat the mixture strongly in 
 an apparatus provided with a condenser. If it be desired to ob- 
 tain considerable benzene a hard glass flask and condensing appa- 
 ratus must be used, and the distillate must be purified by shaking 
 with sodium hydroxide and then with calcium chloride and re- 
 distilling. For the purpose of illustrating this method of obtaining 
 pure benzene, a distillation of 10 grams of benzoic acid with 20 
 
138 ORGANIC CHEMISTRY. 
 
 grams of quicklime will be sufficient. A testtube with bent 
 delivery tube will serve. The residue in the retort is principally 
 calcium carbonate. After cooling, it may be treated with boiling 
 water, filtered, and the material collected on the filter and tested 
 with hydrochloric acid. The presence of a carbonate will be 
 shown by effervescence. 
 
 Experiment 41. Add 4 c.c. of sulphuric acid slowly to 5 c.c. 
 of nitric acid, stirring during the addition. Allow the mixture to 
 cool, place the vessel containing it in cold water and add, with 
 stirring, i c.c. of benzene in small portions, stirring between each 
 addition. Allow the mixture to stand until the action is complete; 
 add considerable water, stir and allow to stand for a time. Nitro- 
 benzene settles as in an emulsion with water. It should be washed 
 several times by shaking it with water and allowing the mixture to 
 settle. The characteristic odor will be noticed. Note also that 
 the product floats in the mixture of acids but sinks in water. 
 The experiment may be conveniently performed in a testtube 
 with foot, as heat is not required. 
 
 Experiment 42. Mix about equal volumes (i c.c. of each) of 
 nitrobenzene, water and hydrochloric acid, and a little granulated 
 tin, or fine tinfoil, cut into very small pieces. Care should be 
 taken not to use common foil as this is largely lead. It may be 
 necessary to warm the mixture slightly to maintain the evolution 
 of hydrogen. The nitrobenzene will be converted into aniline. 
 To detect the latter, slightly dilute the mixture and add a fresh 
 solution of bleaching powder or solution of chlorinated soda. A 
 transient bluish-violet tint will appear. 
 
 Experiment 43. Add a few drops of a dilute solution of ferric 
 chloride to a small amount of salicylic acid in a watch glass or 
 porcelain basin. A violet solution is produced. 
 
 Experiment 44. Mix about o.i gram of salicylic acid with 20 
 c.c. of water, to which a few drops of sodium hydroxide have been 
 added, and shake the liquid until the acid has been dissolved. If 
 the solution does not occur in a few minutes add more sodium 
 hydroxide. The solution will contain sodium salicylate. Add 
 enough sulphuric acid to render the liquid slightly acid, then add 10 
 c.c. of ether and shake well. Allow the mixture to stand until 
 some ether separates, pour this off, evaporate it and test the 
 residue for salicylic acid as noted above. This is an extraction 
 with an "immiscible solvent." 
 
BENZENES. 139 
 
 Experiment 45. Test a small amount of benzoic acid by the 
 method given in Experiment 43. A brown precipitate will be 
 formed. 
 
 Experiment 46. Prepare sodium benzoate and extract benzoic 
 acid from it by the method of Experiment 44, substituting benzoic 
 acid for salicylic. Test the benzoic acid by odor and reaction with 
 iron. 
 
 Experiment 47. Mix a very little aniline with a drop of chloro- 
 form, add a few drops of a strong solution of sodium hydroxide in 
 alcohol, and heat the mass gently by immersing it in warm water. 
 A peculiar and very disagreeable odor will be developed, due to 
 a body called phenylcarbamine or isonitrile, C 6 H 5 NC. 
 
 Experiment 48. Mix i gram of phenol with 6 c.c. of strong 
 sulphuric acid and i c.c. of water; stir and heat for a short time 
 by immersing the testtube in boiling water; 12 and 14 phenol- 
 sulphonic acids are formed. The 13 form cannot be obtained 
 by this method. 
 
 Experiment 49. Liquefy phenol by adding a few drops of 
 water to a gram of the crystals; add some of this liquid to some 
 white of egg. The albumin is coagulated. This is a distinction 
 between phenol and true kreasote, as the latter does not coagulate 
 albumin. 
 
 Experiment 50. Place about 20 c.c. of bromine water in a 
 beaker and stir it with a glass rod carrying a small drop of liquid 
 phenol. A yellowish- white precipitate of tribromphenol is produced. 
 
 Experiment 51. Dissolve about o.i gram 'of potassium nitrate 
 in a few drops of water; evaporate the solution to dryness in a 
 watch glass over the steam bath and add to the residue a few drops 
 of the phenolsulphonic acids obtained in Experiment 48 and smear 
 the liquid over the glass with a glass rod. It will assume a yellow 
 tint owing to the formation of nitrophenols, including picric acid. 
 Add more water and pour the liquid into a small beaker, dilute 
 further with water and then neutralise with ammonium hydroxide 
 or sodium hydroxide. A deep yellow color is developed owing to 
 the formation of a picrate. 
 
 If the mixture of phenol and sulphuric acid be heated for several 
 hours in boiling water, it is mostly changed into a phenoldisul- 
 phonic acid, and the yield of picric acid from this is much greater 
 than that obtained in the above experiment. 
 
 Experiment 52. Dissolve a little saccharin in water, acidulate 
 
140 ORGANIC CHEMISTRY. 
 
 slightly with sulphuric acid and proceed as in Experiment 44. 
 The saccharin will be left as a crystalline residue, the nature of 
 which is easily recognised by its taste. 
 
 Naphthalene, C 10 H 8 , often called coal-tar camphor, is 
 obtained from coal-tar, in the form of white, somewhat 
 fragrant, crystalline scales. It melts at 80. It is 
 slightly soluble in boiling water. It is used extensively 
 to protect goods against moths. Naphthalene consists of 
 a double ring of carbon atoms saturated with hydrogen; 
 thus : 
 
 H H 
 
 H C C C H 
 
 I! I II 
 
 H C C C H 
 
 C C 
 
 A A 
 
 This formula is usually expressed by 
 
 The naphthalene-ring may be oriented in the same 
 manner as the benzene-ring, beginning at the upper right 
 hand angle and numbering in the direction of the num- 
 bers on a clock. 
 
 A substitution of one atom of hydrogen in naphthalene 
 may produce two isomeric derivatives, depending on the 
 position of the substituting body. Substitution at points 
 
BENZENES. 141 
 
 i, 4, 5 or 8 are termed " alpha" derivatives; substitutions 
 at 2, 3, 6 or 7 are termed ''beta" derivatives. Each 
 may be more definitely indicated as shown in one of the 
 ring-symbols. 
 
 Naphthols, hydroxy naphthalenes , C 10 H 7 HO. When naph- 
 thalene is dissolved, in strong sulphuric acid, a mixture of 
 alpha- and betanaphthalenesulphonic acids is obtained. 
 If these be separated and saponified with sodium hy- 
 droxide, each will yield the corresponding hydroxide 
 (naphthol). The two naphthols are much alike, being 
 white, crystalline bodies, freely soluble in alcohol, spar- 
 ingly in water and possessing marked antiseptic and 
 germicide powers. Betanaphthol is almost exclusively used. 
 
 Betanaphthol, (naphthol), is a colorless crystalline powder, 
 soluble in about 1000 parts of cold water, 75 parts of 
 boiling water, very soluble in alcohol, ether, chloroform and 
 alkaline solutions. It becomes slightly yellow on expo- 
 sure to light. It is used as an antiseptic and preservative. 
 
 The naphthols yield sulphonic acids and nitro-deriva- 
 tives exhibiting numerous instances of isomerism. A few 
 of these are of considerable practical importance. 
 
 Dinitro-alphanaphthols . One form is known as Mar- 
 tins' yellow and naphthol yellow. It is a bright yellow 
 powder of high coloring power and has been used as a 
 color for food and confections, but the fact that in large 
 doses it produces functional disturbances, has led to the 
 prohibition of this use. 
 
 Naphthol yellow 5, a sulphonated derivative of naph- 
 thol yellow, is a yellow powder of high coloring power, and 
 being apparently much less active than the latter has 
 displaced it as a food color. 
 
 Abrastol, Asaprol. These are trade names of a calcium 
 betanaphtholsulphonate, used as a food preservative. 
 
I4 2 ORGANIC CHEMISTRY. 
 
 The following structural formulas show several naph- 
 thalene derivatives. 
 
 HO HO 
 
 a-naphthol /?-naphthol a-/3-naphthol 
 
 a-hydroxynaphthalene /3-hydroxynaphthalene 
 
 NH 2 
 
 a-amido-naphthalene 
 
 Anthracene, C 14 H 10 (for structural formula see p. 135). 
 This is present in in the higher -boiling portions of coal- 
 tar. It crystallises in colorless scales that show violet fluor- 
 escence. It melts at 213 and distils at about 360. It is 
 insoluble in water and only slightly in cold alcohol, benzene 
 and carbon disulphide. An important use of anthracene 
 is for the synthetic production of alizarin, the coloring 
 matter of madder-root. The first step in this synthesis 
 is the treatment of anthracene with chromic acid, by which 
 anthroquinone, C 14 H 8 O 2 , is formed. Anthroquinone is 
 converted by means of strong sulphuric acid into a mono- 
 sulphonate, and this, treated with sodium hydroxide and 
 potassium chlorate, yields alizarin. This method of pro- 
 duction has proved so satisfactory that the cultivation of 
 madder (Rubia tinctoria) has been discontinued. 
 
 Anthraquinone, C 14 H 8 O 2 , is a diphenyldiketone (see under 
 Quinones, p. 133), obtained by the oxidation of anthra- 
 cene with chromic acid. It forms yellow crystals. It is 
 
BENZENES. 143 
 
 not an oxidising agent, and, unlike some other quinones, 
 is not reduced by sulphurous acid. Its production from 
 anthracene is a standard method of assaying the crude 
 forms of the latter substance. 
 
 Experiment 53. Dissolve i gram of commercial anthracene 
 in 45 c.c. of glacial acetic acid; filter if necessary, bring to boiling 
 and add a solution of chromic acid in acetic acid by small por- 
 tions. The chromic acid solution is made by dissolving 10 grams 
 of chromic anhydride in 10 c.c. of 50 per cent, acetic acid. This 
 solution should be added until the boiling mixture produces a 
 red stain on a piece of silver which shows that the chromic acid 
 is no longer reduced. Allow the mass to cool, dilute with 150 
 c.c. of water, allow to stand a few hours, collect the precipitate 
 on a filter, wash with water, then with solution of sodium hydrox- 
 ide and again with water. 
 
 Benzidin, diamidodiphenyl, (C 6 H 4 ) 2 (NH 2 ) 2 , belongs to the 
 class of polynucleated cyclic compounds that is constituted 
 of independent rings joined directly at one point, as con- 
 trasted with duplicated rings, such as naphthalene and 
 phenanthrene, or conjugated rings such as phenyl ether, 
 phenazin, anthracene and alizarin. 
 
 Benzidin has lately been brought into notice as appli- 
 cable to the volumetric determination of sulphuric acid 
 and sulphates on account of the insolubility of benzidin 
 sulphate. A solution of benzidin hydrochloride is used in 
 this process. Many of its derivatives are valuable dyes. 
 
 NH 2 
 
144 ORGANIC CHEMISTRY. 
 
 Diphenyl, C 6 H 5 C 6 H 5 , is another compound of the same 
 class as benzidin. 
 
 Carbazol 1-2 imido-diphenyl , (C 6 H 4 ) 2 NH. This exists 
 in crude anthracene as a potassium derivative. It is 
 employed in the preparation of synthetic colors and as 
 a test for nitrates. 
 
 COAL-TAR COLORS. 
 
 The coal-tar colors are a very numerous group of com- 
 pounds obtainable from the hydrocarbons present in the 
 tar. They are all closed-chain derivatives, but not all 
 from benzene. The first color discovered was a violet 
 which Perkin obtained, in 1856, while experimenting with 
 aniline. Hofmann (1859) produced a brilliant red color 
 magenta, from aniline, and the following year the manufac- 
 ture of it was begun. From that date the number rapidly 
 increased and they began to displace the natural colors. 
 In 1868 alizarin, the coloring matter of madder, was 
 obtained by synthesis from anthracene and recently 
 indigo has been made from naphthalene. 
 
 On account of the almost exclusive use of crude aniline 
 in the manufacture of these colors in the early period, 
 they were termed "aniline colors" a name which is still 
 largely used, although some of the most used are not 
 made from aniline or its immediate derivatives. 
 
 As a class these bodies are brilliant in tint, of high 
 coloring power and soluble in water and alcohol. They 
 include every known shade and have to a great extent 
 replaced the natural dyes. They are much used for 
 coloring foods, beverages and household articles, and 
 their sanitary relations have been the subject of much 
 investigation and discussion. 
 
 Their composition is, as a rule, very complex, but as 
 
COAL-TAR COLORS. 145 
 
 nearly all of them are produced from simple substances 
 (e. g., benzene, naphthalene, anthracene) by synthetic 
 methods, the structural formulas are mostly known with 
 certainty. The commercial colors include representatives 
 of all the larger groups of closed-chain derivatives. The 
 important ones are considered in connection with the 
 groups to which they belong. The following list will 
 indicate the variety of types they represent. A few 
 colors not classified elsewhere are here described: 
 
 Nitro- and Nitroso -colors. Picric acid, naphthol yellow, 
 naphthol yellow S, naphthol green. 
 
 Azo -colors. Methyl orange, Bismarck brown, Congo red. 
 
 Ketonic Colors. Alizarin, chrysophanic acid. 
 
 Phenylme thane Derivatives. Auramin, magenta (fuch- 
 sin), malachite green, phenolphthalein, fluorescein, eosins, 
 rhodamines, methyl violet. 
 
 Sulphur Derivatives. Methylene blue. 
 
 As the systematic names of these bodies are generally 
 long and awkward, they are almost always known by 
 commercial titles which are arbitrary and often fanciful. 
 Abbreviations are used to indicate shade, special con- 
 dition or manufacturer. A few of these abbreviations 
 are here noted: 
 
 Letters such as J, JJ, B, BB, OOOO, are descriptive 
 of the shades. Eosin J indicates an eosin with a yellow 
 shade (Fr. jaune)\ German chemists often use G for this. 
 JJ means a stronger yellow shade; OOOO a strong orange 
 shade. S generally means sulphonation ; naphthol yellow 
 S is the sulphonated derivative of naphthol yellow. BASF 
 (Badische Anilin und Soda Fabrik) is an example of a 
 manufacturer's name. 
 
 A few of these colors are insoluble in water. Some 
 azo-colors insoluble in water are soluble in oils, to which 
 
146 ORGANIC CHEMISTRY. 
 
 they impart an orange or yellow tint. They are now 
 often used in coloring fatty foods, especially butter and 
 cheese. Many colors are affected by acid or alkaline so- 
 lutions and are used as indicators. 
 
 Ros aniline. This is produced whenever crude aniline, 
 which always contains toluidines (methylanilines), is 
 treated with oxidising agents. Arsenic acid, nitroben- 
 zene and mercuric nitrate are the oxidising agents practi- 
 cally used. The arsenic acid method was the first and 
 hence all the rosaniline products were liable to contain 
 arsenic. Rosaniline is generally formulated as a deriva- 
 tive from methane by substitution of all its hydrogen 
 by monad groups. 
 
 C 6 H 4 (CH 3 )(NH 2 ) 
 
 C 6 H 4 (NH 2 ) 
 
 C 6 H 4 (NH 2 ) 
 
 OH 
 
 Rosaniline forms salts with acids some of which are 
 important dyes. One of these is: magenta, fuchsin, 
 aniline red, rosaniline hydrochloride. It is soluble in water 
 producing a brilliant red solution of high coloring power. 
 It is used largely for coloring foods and beverages. The 
 name "magenta" is an interesting instance of the fanciful 
 source of these color-names. It refers to the battle at 
 Magenta, Italy, fought in the year in which the color was 
 first prepared. 
 
 Methylene blue, C 16 H 18 N 3 SC1. This is a complicated 
 sulphur derivative, which has been used as a therapeutic 
 agent and also for staining pathologic and bacteriologic 
 preparations. 
 
 Methyl violet, C 24 H 28 N 3 C1, is a product of oxidation of 
 dimethylaniline. It is of very high coloring power and is 
 also an antiseptic. It is used in treatment of ulcers and 
 wounds under the trade name "pyoktanin blue." 
 
TERPENES. 147 
 
 TERPENES. 
 
 The ter penes are cyclic hydrocarbons having the general 
 formula (C 5 H 8 ) n . When oxidised they form camphors and 
 resins. The terpenes may be considered as cyclic com- 
 pounds in which one or more latent valencies exist. 
 
 The formulas on page 148 are suppositions, and only 
 suggestive, but indicate the complexity of the structure of 
 these compounds. 
 
 Many essential oils consist almost entirely of terpenes, 
 others of a mixture of terpenes with oxygenated bodies. 
 The terpenes are capable of polymerisation, and often show 
 optical activity. The natural forms are sometimes com- 
 posed of equivalent proportions of dextro- and levorota- 
 tory modifications. 
 
 The following classification of the terpenes is based upon 
 the differences in their molecular weights : 
 
 1. Hemiterpenes, C 5 H 8 
 
 2. Terpenes, C 10 H 16 
 
 3. Sesquiterpenes, C 15 H 24 
 
 4. Diterpenes, C 2 oH 32 
 
 5. Poly terpenes, n(C 10 H 16 ) 
 
 Pinene, C 10 H 16 , constitutes the principal portion of oil 
 of turpentine. It is a colorless liquid possessing an aro- 
 matic odor. It unites with hydrochloric acid to form 
 pinene hydrochloride, C 10 H 17 C1, which, from its resemblance 
 in physical properties to camphor, has been called "arti- 
 ficial camphor." When oil of turpentine is mixed with 
 alcohol and nitric acid and allowed to stand for several 
 days, a crystalline compound separates which has the 
 composition C 10 H 18 (OH) 2 + H 2 O, and is known as terpin 
 hydrate. This compound forms colorless tabular crystals 
 possessing a slightly aromatic odor and a bitter taste, and 
 is used in medicine as an expectorant. 
 
1 48 
 
 ORGANIC CHEMISTRY. 
 
 H 
 H C H 
 
 i 
 
 HC CH 
 
 H H 
 
 H C H H C H 
 
 / 
 H,C 
 
 HC CH 2 HoC 
 
 V 
 
 CH 
 
 \ 
 CH 
 
 II 
 CH 
 
 \ 
 H 9 H 
 
 H,C CH 
 
 or | / 
 
 HC 
 
 V \ 
 H CH 
 
 \^> 1 A T T V_x T T A A \-s A A 
 
 H 3 C C CH S H-C-C-C-H H-C C C~-H 
 
 i iii iii 
 
 H 
 
 Pinene 
 
 H 
 H C H 
 
 H H H H H H 
 
 Camphene 
 
 H 
 
 H C H 
 H>C-C-C<H 
 
 
 H,C 
 
 \ 
 
 CH. 
 
 H A H 
 
 C H 
 
 H C=C C H 
 
 i A 
 
 i-U-H 
 
 H 
 H 
 
 H C=C C H 
 
 u 
 
 Terpinene 
 (Two arrangements of the suggested formula.) 
 
CAMPHORS. 149 
 
 Camphene, C 10 H 16 , is a white crystalline solid, which can 
 be oxidised to form camphor. 
 
 Limonene, also known as hesperidene, carvene and citrene, 
 constitutes almost the entire portion of several of the 
 volatile oils, notably oil of orange peel. Oil of lemon 
 peel consists of a mixture of pinene and limonene. Many 
 of the volatile oils such as orange and lemon consisting 
 almost entirely of terpenes, lose their characteristic odor 
 upon standing and acquire the odor of oil of turpentine, 
 the change being due to some obscure molecular rear- 
 rangement. This change is usually accompanied by a 
 thickening and resinification of the oil, due to partial 
 oxidation of the terpenes. 
 
 Dipentene, Sylvestrene, Terpinolene, Ter pinene and Phel- 
 landrene, all have the formula C 10 H 16 and possess similar 
 properties to the terpenes already described. 
 
 Terebene is a mixture of several of the terpenes (pinene, 
 terpinene and dipentene) and is produced by the action 
 of sulphuric acid on oil of turpentine. 
 
 Members of the classes sesquiter penes, C 15 H 24 , and diter- 
 penes, C 20 H 32 , are found in some volatile oils. 
 
 Colophene, C 20 H 32 , is a diterpene, which is formed as a 
 by-product in the manufacture of terebene. 
 
 Polyterpenes (C 10 H 1 - 6 ) X , exist in caoutchouc and gutta 
 percha and may be formed by the polymerisation of oil 
 of turpentine. 
 
 CAMPHORS. 
 
 The camphors are oxygenated derivatives of the ter- 
 penes. They are sometimes called stearoptenes to dis- 
 tinguish them from the eleoptenes or liquid portions of the 
 volatile oils in which they usually occur. Some of them 
 
150 ORGANIC CHEMISTRY. 
 
 are alcohols while others resemble the ketones. They 
 are completely volatile without decomposition and may 
 be purified by sublimation. 
 
 Ordinary camphor, C 10 H 16 O, sometimes called Japan 
 camphor, is obtained by distilling the wood of a species 
 of cinnamon (Cinnamomum camphora) in a current of 
 steam. It has also been obtained synthetically from oil of 
 turpentine by converting the pinene into camphene which 
 readily yields camphor by oxidation. 
 
 Camphor is a crystalline solid, possessing a character- 
 istic odor and a pungent, afterward a cooling, taste. It is 
 sparingly soluble in water but readily soluble in alcohol, 
 ether, chloroform, petroleum spirit and fixed and volatile 
 oils, the solution of the natural product being dextro- 
 rotatory. It can be ignited readily and burns with a 
 luminous, smoky flame. With bromine, camphor forms 
 a derivative known as monobromated camphor, C 10 H 15 BrO, 
 which forms colorless, prismatic crystals, melting at 76 
 with a slight odor and a pungent camphoraceous taste. 
 
 Borneol or Borneo camphor, C 10 H 18 O, is obtained in a 
 similar manner to ordinary camphor from the wood of 
 Dryobalanops aromatica. It may be obtained from or- 
 dinary camphor by the action of sodium. 
 
 LiwaZ0oJ,C 10 H 17 OH; GVramW, C 10 H 17 OH; CY/ra/,C 10 H 16 O, 
 and Citronellal, C 10 H 20 O, are odorous bodies belonging to 
 this class, obtained from certain volatile oils, citral being 
 present in oil of lemon. 
 
 Menthol, C 10 H 20 O, is the stearoptene obtained from 
 volatile oils of several varieties of peppermint. Menthol 
 forms colorless, needle-shaped crystals melting at 46 
 having a warm mint -like taste, followed by a cooling sen- 
 sation when air is inhaled through the mouth. 
 
ESSENTIAL OILS. 151 
 
 ESSENTIAL OILS. 
 
 Essential oils, often called volatile oils, are the liquid 
 proximate constituents to which the characteristic odors 
 of plants are due. They are obtained from flowers, seeds, 
 leaves, stems, barks and roots, mostly by distillation with 
 water, the volatile oil passing over with the steam and 
 condensing with it. Some of the aromatic waters used 
 in medicine, such as rose water and orange flower water, 
 are obtained as by-products in the distillation of the 
 essential oils. The essential oils are usually mixtures of 
 terpenes and camphors although some consist of esters, 
 aldehydes or ketones. 
 
 The ESSENTIAL OILS are distinguished by their complete 
 volatility, comparative insolubility in water and complete 
 solubility in alcohol, ether, chloroform and similar solvents. 
 They are sometimes obtained by expression, as with oils 
 of orange and lemon, and may be extracted from the plant 
 tissues by the use of appropriate solvents. They may be 
 divided into four classes, viz.: 
 
 Terpenes: Oils consisting mainly of members of the 
 class of terpenes, as oil of lemon. 
 
 Oxygenated: Oils consisting of aldehydes, esters or 
 ketones often associated with small amounts of terpene, 
 as oil of cinnamon. 
 
 Sulphurated: Containing sulphur, as oil of mustard. 
 
 Nitrogenated : Containing nitrogen, as oil of bitter 
 almond. 
 
 It will be impossible to give more than a brief outline of 
 some of the important volatile oils. 
 
 Oil of turpentine is obtained by the distillation of the 
 natural oleoresin of Pin us palustris: it consists almost 
 entirely of pinene. 
 
152 ORGANIC CHEMISTRY. 
 
 Oil of anise is principally composed of anethol, a meth- 
 oxy-derivative of benzene. 
 
 Oil of black mustard is allyl isothiocyanate associated 
 with a small amount of carbon disulphide. 
 
 Oil of cinnamon is principally cinnamic aldehyde. 
 
 Oil of cloves and oil of pimenta consist mainly of eugenol 
 (allylguaiacol). 
 
 Oil of lavender flowers consists almost entirely of linalool 
 and geraniol. 
 
 Oil of lemon consists of pinene, limonene (a dextro- 
 rotatory terpene), citral and a small amount of citronellal. 
 
 Oil of orange peel consists mainly of limonene and 
 geraniol. 
 
 Oil of pennyroyal contains several ketones, the principal 
 one being pulegone. 
 
 Oil of peppermint is very complex in its constitution. 
 It contains pinene, limonene, aldehydes, alcohols and 
 esters. 
 
 Oil of rose contains geraniol associated with a hydro- 
 carbon having the formula C 20 H 42 . 
 
 Oil of sassafras contains safrol, eugenol, pinene and a 
 benzene derivative. 
 
 Oil of sweet birch and oil of gaultheria consist of methyl 
 salicylate, associated with a small amount of terpene. 
 
 Oil of violets, so called, is a product obtained from 
 essential oil of orris. In concentrated form it bears very 
 little resemblance in odor to violets, but when largely 
 diluted with alcohol the odor is similar. 
 
 RESINS. 
 
 The resins are also products resulting from the oxidation 
 of the terpenes and are associated in plant tissues with 
 
RESINS. 153 
 
 other proximate principles, such as volatile oils and gums. 
 They usually exhibit the characters of acids or anhydrides 
 and are decomposed by strong heat. They are divided 
 into three groups: i, true resins; 2, oleoresins; 3, gum- 
 resins. 
 
 The hard or true resins, of which ordinary resin or 
 colophony (sometimes called rosin) is a type, are fusible 
 solids capable of crystallisation under favorable conditions, 
 insoluble in water, but soluble in one or more of the follow- 
 ing solvents: alcohol, ether, chloroform, carbon disul- 
 phide, acetone, petroleum spirit, benzene and fixed or 
 volatile oils. They often combine with alkaline hydroxides 
 to form compounds known as resin soaps. They are con- 
 tained in various plant tissues and are often obtained as 
 exudations from living plants, in which case they may 
 be pathological products, caused by wounding the tissues 
 in which they exist. 
 
 Colophony or common resin is obtained as a residue 
 when the oleoresin of the pine tree is distilled for obtaining 
 oil of turpentine. It consists largely of abietic anhy- 
 dride, C 44 H 62 O 4 , which is converted into abietic acid by the 
 action of alcohol and water. 
 
 Dammar, Copal and Amber are fossil resins used in the 
 manufacture of varnishes and lacquers. 
 
 Lac is a resinous exudation from several species of 
 oriental trees, occasioned by the puncture of an insect. 
 
 Shellac is the purified product occurring in thin, trans- 
 parent layers. 
 
 Guaiac resin exists in the bark and heartwood of a 
 West-Indian tree. It yields protocatechuic acid when 
 fused with potassium hydroxide and is decomposed by 
 destructive distillation into guaiacol and allied products. 
 
 Crude turpentine, Burgundy pitch and Copaiba are 
 
154 ORGANIC CHEMISTRY. 
 
 natural oleoresins, the consistency being liquid or semi- 
 solid according to the amount of volatile oil associated with 
 the resin. 
 
 Balsams are oleoresins which are associated with aro- 
 matic products, such as benzoic or cinnamic acid. The 
 principal balsams are Benzoin, Balsam Peru, Balsam 
 Tolu and Storax, all of which are used in medicine. 
 
 The gum resins usually exist in the plants from which 
 they are derived, in the form of a milky juice. Upon fusing 
 the gum resins with potassium hydroxide they yield 
 resorcin and protocatechuic acid. The principal gum 
 resins are Asafetida, Ammoniac, Myrrh and Gamboge. 
 
 Caoutchouc and gutta percha are polyterpenes which 
 exist in many plants in the form of an emulsion or milky 
 juice. 
 
 HETEROCYCLIC COMPOUNDS. 
 
 The closed chains so far described are assumed to con- 
 tain only carbon atoms. Many compounds are known in 
 which the ring consists of carbon atoms with an atom of 
 oxygen, sulphur or nitrogen. These are termed hetero- 
 cyclic compounds. Nitrogen carries with it one hydrogen 
 atom (see Pyrrol). 
 
 The following is a synopsis of the most important groups 
 of this type: 
 
 THREE-MEMBERED RINGS. Among these are found 
 bodies which might be classed as open-chain compounds, 
 such as ethene oxide, C 2 H 4 O, of which the structural 
 
 H 2 C^ 
 
 formula must be: I/O 
 H 2 C X 
 
 FOUR-MEMBERED RINGS. In these is included betaine, 
 the structural formula of which is given in the section on 
 Ptomaines. The ring is the series NOCC. 
 
HETEROCYCLIC COMPOUNDS. 155 
 
 FIVE-MEMBERED RINGS. These include several im- 
 portant types of compounds. 
 
 Furfur ane: four carbon and one oxygen atom. 
 
 Thiophene: four carbon and one sulphur atom. 
 
 Pyrrol: four carbon and one nitrogen atom. 
 
 Of the very many derivatives that these bodies may 
 yield, only a few of special importance can here be noted. 
 
 Furfurane, C 4 H 4 O, is present in the materials collected 
 from the distillation of pine wood. It is of less interest 
 than its aldehyde. 
 
 Furfural, C 4 H 3 (HCO)O, often termed furfurol, is pro- 
 duced in the destructive distillation of, or action of strong 
 acids upon, bodies containing carbohydrates, and in small 
 amount in alcoholic fermentation. Lately, a suggestion 
 has been made that the comparatively higher poisonous 
 action occasioned by newly-prepared alcoholic beverages 
 is due to furfural and not, as formerly supposed, to or- 
 dinary aldehyde or amyl alcohols. Furfural is a colorless 
 liquid with an aromatic odor. It has well marked al- 
 dehydic properties. It is used for a few special tests in 
 food analysis. 
 
 Experiment 54. Ten grams of wheat bran are mixed in a 500 
 c.c. flask with 70 c.c. of water and 3 c.c. of sulphuric acid. The 
 flask is connected with a condensing arrangement and the mixture 
 cautiously distilled until about 20 c.c. have passed over. The 
 distillate contains furfural. For a test for it, see under Phenyl- 
 hydrazin. 
 
 Coumarin. This is a crystalline principle existing in 
 the tonka bean. Its odor is sufficiently like that of vanillin, 
 to cause the tonka bean to be used very much as a sub- 
 stitute for vanilla. The molecule of coumarin is a com- 
 bination of an oxidised furfurane ring with a benzene 
 ring. 
 
156 ORGANIC CHEMISTRY. 
 
 Thiophene, C 4 H 4 S, may be regarded as benzene in 
 which two atoms of carbon are replaced by sulphur. The 
 principal interest attaching to it is that it is a frequent 
 impurity of benzene. It gives color reactions that hy- 
 drocarbons do not give, but its presence in benzene was 
 long unrecognised and its reactions were ascribed to 
 benzene itself until the impurity was discovered. Thio- 
 phene resembles benzene in many properties. 
 
 Pyrrol, C 4 H 4 NH, is found in bone oil and coal-tar. It 
 can be prepared synthetically. It is a colorless liquid 
 with an odor recalling that of chloroform. 
 
 According to the system of nomenclature now in vogue 
 the termination "ol" is not appropriate to this compound. 
 The name "pyrrin" would be more systematic. 
 
 SIX-MEMBERED RINGS, PYRiDiNS. This is a series of 
 bodies that contain nitrogen atoms in a closed chain with 
 carbon atoms. This grouping, known as the "pyridin 
 ring," is a stronger molecular linking than even benzene, 
 and the opportunities for isomerism are also greater than 
 with benzene. The type compound is: 
 
 Pyridin, C 5 H 5 N. This was first noted in the offensive 
 liquor obtained by distilling bones, formerly used in 
 medicine under the name " Dippel's animSl oil." It is 
 found in coal-tar. Pyridin is a liquid with a disagreeable 
 odor, boiling at a temperature somewhat above that of 
 boiling water. It is a monacid base combining, as is usual 
 with nitrogen bases, with the entire acid molecule. It also 
 unites with alkyl iodides, such as methyl iodides; these 
 compounds decomposed by silver hydroxide, yield hydroxyl 
 bases analogous to the substitution ammoniums. 
 
 Quinolin. The pyridin ring associated with a benzene 
 ring, gives rise to quinolin, which bears the same struc- 
 tural relation to pyridin that naphthalene does to benzene. 
 
HETEROCYCLIC COMPOUNDS. 157 
 
 The structural formations of these two bodies are shown 
 in the annexed drawings in which the atoms are represented 
 by special signs. It is to be noted that while pyridin cannot 
 exist in more than one form, since the nitrogen atom may 
 be placed at any angle of the chain without altering the 
 relations of the other atoms to it, the quinolin group is 
 capable of two modifications as shown. Neither pyridin 
 nor quinolin contains asymmetric carbon and, therefore, 
 has no optical activity. 
 
 Quinolin is a colorless liquid of high dispersive power. 
 It is produced in the destructive distillation of coal, bones 
 and many alkaloids. It has been obtained synthetically. 
 Pyridin and quinolin are of much interest not only on 
 account of the large number of derivatives they yield, but 
 principally because their molecular structure is present 
 in many alkaloids. 
 
 H H H 
 
 I 
 
 H 
 
 Quinolin 
 The round dots represent carbon atoms ; the rectangular represent 
 
 nitrogen atoms 
 (Diagrammatic formulas.) 
 
 There is as yet no uniform method of representing the 
 pyridin ring. In this book it is represented by benzene 
 ring-symbol with a small "N" attached close to one of the 
 angles, as shown in the annexed formula: 
 
158 ORGANIC CHEMISTRY. 
 
 H H 
 
 I i 
 
 r 
 
 H H 
 
 Pyridin symbol Quinolin symbol Iso-quinolin 
 
 = C 5 H 5 N " =C 9 H 7 N 
 
 Homologous Derivatives. The hydrogen of all these 
 molecules may be replaced by the alkyl radicles, thus 
 forming homologous series. A few of these deserve 
 mention. 
 
 Methyl Pyridins. These are : 
 
 Picoline, C 5 (CH 3 )H 4 N 
 Lutidine, C 5 (CH 3 ) 2 H 3 ^ 
 Collidin, C 5 (CH 3 ) 3 H 2 N 
 
 The first substitution will exist in three forms, the 
 methyl radicle standing either in the 1-2, 1-3 or 1-4 posi- 
 tion to the nitrogen. The further substitutions will show 
 still more numerous instances of isomerism. 
 
 Additive Compounds. As with benzene and naphthalene 
 the latent valencies of these closed chains may be de- 
 veloped, and a series of derivatives obtained in which the 
 original hydrogen is not disturbed. 
 
 Piperidin, Pyridin hydrid, C 5 H U N, is closely related 
 to conine, as the annexed formulas show. 
 
 Conine is a substitution of propyl (trityl), C 3 H 7 , for the 
 additive hydrogen atoms in piperidin nearest to the 
 nitrogen, and is therefore, 1-2 propylpiperidin. The 
 
HETEROCYCLIC COMPOUNDS. 
 
 159 
 
 introduction of the alkyl radicle makes the carbon atom 
 to which it is attached asymmetric. Conine is known to 
 exist in several forms, respectively, dextro- and levo- 
 rotatory, and inactive. The natural conine is dextro- 
 rotatory. 
 
 H H 
 
 C 3 H 7 
 
 Pyridin hydrid 
 (Piperidin) 
 
 Piperin. This substance is an abundant ingredient 
 of all forms of pepper. Its empirical formula is identical 
 with that of morphine, but it is not an alkaloid, and is 
 structurally wholly different from morphine as the an- 
 nexed formula shows. It contains a pyridin and a ben- 
 zene ring. Piperin must not be confounded with the 
 diamine, piper azin. 
 
 O CH 2 
 
 O 
 
 Piperin 
 
CYANOGEN AND DERIVATIVES. 
 
 Nitrogen and carbon do not combine by simple contact, 
 but if nitrogen be passed over a mixture of carbon and 
 potassium carbonate, potassium cyanide, KCN, is formed. 
 From this, other cyanides may be obtained. By heating 
 mercuric cyanide, Hg(CN) 2 , free cyanogen, C 2 N 2 , is formed. 
 This is a colorless, poisonous gas. 
 
 Cyanides may be formed from proteid matters. This may be 
 illustrated by placing a small piece of dried albumin and a little 
 sodium in the closed end of a glass tube, heating to redness for 
 about a minute and dipping the heated portion into a little water. 
 The tube will break and its contents partly dissolve. The solution 
 will react to the tests for cyanides, as given below. 
 
 Two forms of cyanogen compounds are known termed, 
 respectively, cyanides and isocyanides, as follows: 
 
 Potassium cyanide. Potassium isocyanide. 
 
 K C=N C=N K 
 
 In the former nitrogen is triad, in the latter, pentad. 
 Potassium Cyanide, KCN. This body, prepared usually 
 by decomposing some more complex cyanides, is a snow- 
 white mass, very soluble in water, and easily decomposed 
 even by the carbonic acid of the air, hydrogen cyanide 
 being formed. Potassium cyanide dissolves many silver 
 compounds that are insoluble in water. It is used in 
 making solutions for silver-plating and in photography, 
 also in very small doses as a medicine. It is an active 
 poison. Oxidising agents convert it into potassium cya- 
 nate. Commercial potassium cyanide generally contains 
 cyanate and sodium cyanide. 
 
 1 60 
 
CYANOGEN AND DERIVATIVES. l6l 
 
 Hydrogen Cyanide, HCN. This is generally called 
 hydrocyanic or prussic acid. When pure, it is a colorless 
 liquid, easily decomposed and intensely poisonous, As 
 sold for medical purposes (Acidum hydrocyanicum dilu- 
 timi), it is very dilute, consisting of two parts of acid to 
 ninety-eight of water. It has, even when much diluted, 
 a strong odor suggesting bruised peach kernels ; in fact, 
 hydrogen cyanide is formed from these substances by the 
 decomposition of nitrogenous principles when the seeds 
 are crushed with cold water. This occurs under the in- 
 fluence of enzyms, for if these are first coagulated by 
 boiling alcohol, no decomposition occurs. The reaction 
 by which hydrogen cyanide is formed when bitter almonds 
 are macerated with water consists in the hydrolysis of a 
 crystalline principle called amygdalin, under the in- 
 fluence of an enzym called synaptase: 
 
 Benzal- Hydrogen 
 Amygdalin. dehyde. cyanide. Glucose. 
 
 C 20 H 27 NO U + 2 H 2 = C 7 H 6 + HCN + 2C 6 H 12 O 6 
 
 Hydrogen cyanide may also be made by decomposing other 
 cyanides by strong acids, thus: 
 
 2 KCN + H 2 SO 4 = K 2 SO 4 + 2HCN 
 AgCN + HC1 = AgCl + HCN 
 
 The latter reaction is utilised in the pharmaceutical 
 preparation of the dilute acid. 
 
 Complex Cyanides. The potassium group cyanides 
 show a great tendency to combine with other cyanides, 
 especially those of the iron group, to form complex cya- 
 nides, in which some properties of the simpler cyanides, 
 especially the poisonous qualities, are much diminished. 
 The iron series is the most important. Two well-marked 
 compounds are known. 
 
162 ORGANIC CHEMISTRY. 
 
 Potassium ferrocyanide, K 4 C 6 N 6 Fe, often called yellow 
 prussiate of potash, is made by heating a mixture of nitrog- 
 enous organic matter, iron scraps, and potassium car- 
 bonate, treating the mass with water and allowing it to 
 crystallise. Large lemon-yellow crystals are formed, 
 which are not actively poisonous. Oxidising agents 
 convert it into: 
 
 Potassium ferricyanide K 3 C 6 N 6 Fe, commonly called 
 red prussiate of potash. It forms large ruby-red crystals, 
 soluble in water. The reactions with some substances 
 are so distinct as to constitute very delicate tests. With 
 ferrous compounds, for instance, the ferricyanides give a 
 dark-blue precipitate; ferric salts give, with ferrocyanides, 
 a similar blue precipitate Prussian blue. The two 
 precipitates are nearly identical in composition. An 
 intermediate compound is known as soluble Prussian blue, 
 being soluble in pure water, but insoluble in water con- 
 taining ordinary mineral salts. 
 
 Nitroprussic acid. By the action of nitric acid upon 
 potassium ferrocyanide, an acid-like body is formed, the 
 structure of which is not understood. It is provisionally 
 termed nitroprussic acid. Its importance lies in the fact 
 that its sodium salt, Na 2 Fe(CN) 5 NO, generally called so- 
 dium nitroprussid, is a test for sulphur and for formaldehyde. 
 
 Tests for Cyanides. The recognition of cyanogen is a 
 matter of importance in toxicology. The tests can be 
 directly applied only to the simple cyanides; the double 
 cyanides usually give the reactions after being decom- 
 posed by acids. 
 
 Silver nitrate gives a white precipitate of silver cyanide, 
 which is soluble in boiling nitric acid. 
 
 A mixture of ferrous sulphate and sodium hydroxide, 
 
CYANOGEN AND DERIVATIVES. 163 
 
 when agitated with a cyanide and then treated with acid, 
 will produce a blue precipitate. 
 
 When hydrogen cyanide is brought into contact with 
 ammonium sulphide, a compound called ammonium 
 thiocyanate is formed, which gives, with ferric chloride a 
 blood-red color. 
 
 Experiment 55. Dissolve about 0.5 gram of potassium cyanide 
 in 20 c.c. of water. Put a few drops of this solution in a watch- 
 glass, add a drop of dilute sulphuric acid, and invert over the 
 mixture another watch-glass containing a drop of silver nitrate 
 solution. Hydrogen cyanide will be formed and some of it will pass 
 off as vapor and form silver cyanide on the upper glass. 
 
 Experiment 56. Repeat Experiment 55, substituting a drop 
 of ammonium sulphide for the silver nitrate. The vapor of hydro- 
 gen cyanide will form ammonium thiocyanate. After about five 
 minutes, touch the spot in the upper glass with a rod dipped in 
 ferric chloride. A bright red stain of ferric thiocyanate will appear. 
 
 Experiment 57. To 5 c.c. of the potassium cyanide solution, 
 in a testtube, add a few drops of ferrous sulphate solution and 
 then a little sodium hydroxide. A precipitate consisting prin- 
 cipally of ferrous hydroxide forms. Pour the mass from one 
 testtube to another ^for a short time, then add, cautiously, hydro- 
 chloric acid in slight excess. A precipitate of ferric ferrocyanide 
 (Prussian blue) will be obtained. This is destroyed by excess of 
 alkali but re-formed by acid. 
 
 Experiment 58. Heat in a small glass tube, sealed at one end, 
 a small amount of mercuric cyanide. Cyanogen is liberated and 
 will burn at the mouth of the tube with a characteristic peach- 
 blossom flame. At the upper part of the tube a brown deposit 
 of a polymeric form, termed paracyanogen will collect. 
 
 Cyanogen hydroxides, Cyanic acids. Cyanogen unites 
 with hydroxyl to form several compounds that have the 
 same percentage composition, but some are stereo-isomers, 
 others polymers. Both forms of cyanogen form these 
 compounds. Three important forms are: 
 
 : N=C O H H N=C=O C=N O H 
 Cyanic acid Isocyanic acid Fulminic acid 
 
164 ORGANIC CHEMISTRY. 
 
 Cyanuric acid, H 3 C 3 N 3 O 3 , is of more complex structure. 
 Fulminuric acid has the same empirical formula as cyanuric 
 acid, but is a nitro-derivative and, therefore, of entirely 
 different type. 
 
 The important derivatives of these acids are the cyanates 
 and fulminates. 
 
 Potassium cyanate. The common cyanate is isocyanate, 
 KNCO. It exists in considerable amount in commercial 
 potassium cyanide and can be obtained by heating cyanides 
 with lead oxides. 
 
 Ammonium cyanate, NH 4 NCO, is of interest because it 
 may be transformed by heating into urea, (NH 2 ) 2 CO. 
 This transformation was the first instance of organic 
 synthesis and its accomplishment broke down the lines 
 between organic and inorganic chemistry. The change 
 is a rearrangement as follows: 
 
 H O H 
 
 I H I 
 H 4 N N = C=O H N C N H 
 
 Ammonium cyanate Urea 
 
 Fulminates. As the name indicates, many of these 
 are explosive. Mercuric Culminate, Hg(CNO) 2 , is prepared 
 by heating a mixture of alcohol, nitric acid and mercuric 
 nitrate. It crystallises in needles. It explodes violently 
 on percussion, and is the material used in percussion caps 
 for firearms. 
 
 Silver Culminate, AgCNO, is more explosive than the 
 mercuric salt. 
 
 Thiocyanates . These compounds, often called sulpho- 
 cyanates, are analogous to the cyanates and are obtained 
 in a similar manner, that is, by direct addition of sulphur, 
 
CYANOGEN AND DERIVATIVES. 165 
 
 but the molecular arrangement is not identical in the two 
 actions. 
 
 The common cyanate is isocyanate, as already noted 
 (See formula of potassium cyanate.) Oxygen attaches itself 
 in preference to the carbon and nitrogen atoms, but sulphur 
 attaches itself to the other positive element, hydrogen or 
 metal. The contrast is shown in the structural formulas: 
 
 K N= C=O N=C S K 
 
 Common potassium cyanate Common potassium thiocyanate 
 (Isocyanate) 
 
 The soluble thiocyanates produce with ferric com- 
 pounds a bright red solution of ferric thiocyanate. This 
 reaction is a delicate test for ferric compounds. No color 
 is produced with ferrous compounds. 
 
 The known esters of thiocyanic acid are of the iso- 
 thiocyanic type. They are sometimes termed " mustard 
 oils," as the volatile oil of black mustard is allyl iso- 
 thiocyanate, (C 3 H 5 )NCS. As noted elsewhere, it does 
 not exist in the seed, but is produced by a decomposition 
 under the influence of a special enzym. 
 
 H 2 Cn:C CH 2 
 
 H N 
 
 II 
 s=c 
 
 Allyl isothiocyanate 
 (Mustard oil) 
 
 Azoimide, Hydr azoic acid. An interesting connecting 
 link between inorganic and organic chemistry is furnished 
 by this substance. It has the empirical formula N 3 H. 
 The structural formula is considered to be : 
 
l66 ORGANIC CHEMISTRY. 
 
 N=N N=N 
 
 V V 
 
 NH N NH 4 
 
 Azoimide Ammonium hydrazoate 
 
 (Hydrazoic acid) 
 
 It was first prepared from an amine derivative of benzene, 
 benzoyl nitride, by treatment with sodium ethylate, the 
 following reaction occurring: 
 
 Sodium ethylate. Benzoyl nitride. Sodium hydrazoate Ethyl benzoate. 
 
 NaC 2 H 5 O + C 6 H 5 CON 3 = NaN 3 + C 6 H 5 CO 2 C 2 H 5 
 
 Hydrazoates may be prepared by several other methods 
 some of which are not strictly organic. From the salt 
 the hydrogen compound may be obtained. It is a color- 
 less mobile liquid of very disagreeable odor, and highly 
 explosive. It resembles the halogen acids in many 
 properties. Its ammonium salt, NH 4 N 3 , has the em- 
 pirical formula H 4 N 4 . 
 
 AMMONIUM DERIVATIVES. 
 
 Amines and Amides. Amine, NH 3 , ammonia, is al- 
 ways found, either free or combined, among the products of 
 decomposition of nitrogenous matter. One of the most 
 striking properties of free amine is its power to neutralise 
 acids. When certain organic bodies containing nitrogen 
 were found to have a similar property, a similar con- 
 stitution was assigned to them. Morphine and quinine, 
 which, like amine are decidedly alkaline, and contain 
 considerable nitrogen, have been regarded as ammoniacal 
 in character. Although efforts to produce these bodies 
 synthetically have succeeded only to a limited extent, 
 
AMMONIUM DERIVATIVES. 167 
 
 yet many substances resembling them in composition have 
 been obtained, and no doubt need now exist as to the es- 
 sential nature of these products, or as to the possibility of 
 ultimately producing them. Many of the synthetic bases 
 now known are produced by the substitution of the hy- 
 drogen or nitrogen in amine, NH 3 , or ammonium, NH 4 , by 
 different elements or radicles. The number of compounds 
 so produced is greatly increased by the fact that these 
 molecules are capable of polymerism, so that one set of 
 compounds may be formed on the type NH 3 , and another 
 on that of N 2 H 6 , and so on. A very complete and syste- 
 matic nomenclature has been adopted for these compounds. 
 In the first place, the character of the replaceable radicles, 
 and, to a certain extent, therefore, the character of the 
 compound itself, is indicated by the termination. When 
 the radicle is positive, and especially when it does not 
 contain oxygen, "ine" is used; when negative and con- 
 taining oxygen, " l ide" is used. When the nitrogen is 
 replaced by some member of its group (B, P, As, Sb and 
 Bi), some distinct syllables of these names are added. 
 The names of all the radicles entering into the compound 
 are attached. If the molecule is duplicated, the syllables 
 "di," ll tri," etc., are used to indicate the degree of dupli- 
 cation. If the compound is derived from the type NH 4 
 it has the termination "onium." The following list will 
 show all these points: 
 
 NH 3 , amine; N 2 H 6 , diamine; N 3 H 9 , triamine; N 4 H 12 , tctramine. 
 
 PH 3 , phosphine; P 2 H 6 , diphosphine. 
 
 AsH 3 , arsine. 
 
 SbH 3 , stibine. 
 
 NH 4 , ammonium; N 2 H 8 , diammomum; N :J H 12 , triammonium. 
 
 PH 4 , phosphonium. 
 
 AsH 4 , arsonium. 
 
 SbH 4 , stibonium. 
 
l68 ORGANIC CHEMISTRY. 
 
 The polymerisation of the molecules takes place by 
 introduction of radicles of dyad or higher valency. The 
 methods of producing these substitution compounds are 
 various; one of the simplest is by heating solutions of 
 amine with bromides or iodides of the radicles to be sub- 
 stituted. Thus, an alcoholic solution of amine and ethyl 
 iodide heated for some hours in a sealed tube, gives the 
 reaction : 
 
 NH 3 + (C 2 H 5 )I = (C 2 H 5 )H 3 NI 
 
 As NH 4 I is ammonium iodide so the above compound is 
 called ethylammonium iodide. By further action the 
 whole of the hydrogen may be replaced by ethyl, and we 
 get (C 2 H 5 ) 4 NI, tetrethylammonium iodide. Each of the 
 hydrogen atoms may be replaced by a different radicle, 
 by which great complexity in structure and nature arises. 
 Thus: 
 
 (C 2 H 5 ) 2 (C 5 H 11 )HNI diethylpentylammonium iodide. 
 
 (C 2 H 5 ) 3 (C 5 H 11 )NI triethylpentylatnmonium iodide. 
 
 (CH 3 )(C 2 H 5 )(C 3 H 7 )(C 4 H 9 )NI . . . methylethylpropylbutylammonium 
 
 iodide. 
 
 From NH 3 we may derive: 
 
 (C 2 H 5 )H 2 N ethylamine. 
 
 (C 2 H 5 ) 2 HN diethylamine. 
 
 (C 2 H 5 ) 3 N triethylamine. 
 
 When but one-third of the hydrogen is substituted, the 
 body is said to be primary; when two-thirds are substi- 
 tuted, it is secondary; when all is substituted, the body 
 is tertiary. Ethylamine for instance, is a primary mon- 
 amine. The following structural formulas show some of 
 these bodies : 
 
AMMONIUM DERIVATIVES. 169 
 
 H 
 
 H C H 
 
 CH 3 H 3 C CH 3 
 
 I I v 
 
 H N H H 8 C N CH 8 H 3 C N CH 3 
 
 Methylamine Trimethylamine Tetramethylammonium 
 
 chloride 
 
 Diamines and diammoniums. These always contain N 2 : 
 
 (C 2 H 4 )H 4 N 2 ethenediamine (ethylenediamine) . 
 
 (C 2 H 4 )H 6 N 2 (HO) 2 ethenediammonium hydroxide. 
 
 Triamines, and triammoniums , tetr amines and tetr am- 
 moniums, are formed on the same principle. 
 
 The following formulas show some of the compounds 
 obtained by these elaborate substitutions and when the 
 nitrogen is replaced by other members of its group : 
 
 Ethyl phosphine. Diethyl phosphine. Triethyl phosphine. 
 
 (C 2 H 5 )H 2 P (C 2 H 5 ) 2 HP (C 2 H 5 ) 3 P 
 
 Trimethyl arsine. Tripentyl stibine. Triethyl bismine. 
 
 (CH 3 ) 3 As (C 4 H n ),Sb (C 2 H 5 ) 3 Bi 
 
 Triethyl borine. 
 
 (C 2 H 5 ) 3 B 
 
 Tetrethylphosphonium hydroxide. Tetrethylstibonium iodide. 
 
 P(C 2 H 5 ) 4 HO Sb(C 2 H 5 ) 4 I 
 
 By a combination of radicles of different valencies we 
 may get such a body as: 
 
 (CH 3 ) 3 (C 2 H 5 ) 3 (C 2 H 4 )H 4 P 3 I 3 , trimethyltriethylethenetriphosphon- 
 ium iodide. 
 
 Several complex amines are used in medicine. Among 
 these are : 
 
I 70 ORGANIC CHEMISTRY. 
 
 Hexmethenetetramine, (CH 2 ) 6 N 4 , which is made by adding 
 ammonium hydroxide to formaldehyde. The reaction 
 is a dehydrolysis : 
 
 6CH 2 + 4 NH 4 HO .. (CH 2 ) 6 N 4 + ioH 2 O 
 
 The product is a colorless, almost inodorless, crystalline 
 mass, soluble in water. It is now sold under proprietary 
 names e. g., formin, cystogen, urotropin for the treat- 
 ment of purulent affections of the kidneys and bladder. 
 When taken internally it is decomposed into formaldehyde 
 and ammonium hydroxide. The former is largely excreted 
 by the kidneys and thus exercises its antiseptic action 
 over the mucous membranes of the genito-urinary tract. 
 
 Experiment 59. To 10 c.c. of commercial formaldehyde solu- 
 tion add small amounts of ammonium hydroxide, testing between 
 each addition by a drop of the solution on red litmus paper, until 
 the reaction becomes alkaline. Allow the mixture to stand for 
 some hours and then evaporate it at a low temperature. The 
 tetramine will separate as a white crystalline mass. 
 
 Piper azin is ethenediamine (ethylenediamine). It forms 
 yellowish crystals, soluble in water. It is strongly basic, 
 and has been used in the treatment of diseases supposed 
 to be associated with excessive excretion of uric acid, as 
 piperazin urate is very soluble in water. Piperazin must 
 not be confounded with piperin. 
 
 H H 
 
 H C C H 
 H N N H 
 H C C H 
 
 H H 
 
 Piperazin 
 
AMMONIUM DERIVATIVES. 171 
 
 Amides.^ All primary monamines may be expressed as 
 substitutions of amidogen, NH 2 , for other monads. When 
 the amidogen is associated with a substantially positive 
 group, the compound is basic and is called an amine, but 
 when associated with negative groups it may form either 
 acid or neutral bodies which are called amides. Thus, 
 amidogen may be substituted for the hydrogen of benzene, 
 giving rise to C 6 H 5 NH 2 , amidobenzene, which is basic, and 
 is therefore an amine. Substituted for the hydrogen 
 of acetic acid it gives amidoacetic acid, in which some of 
 the acid properties are retained; but substituted for the 
 hydroxyl of acetic acid it entirely removes the acid func- 
 tion, forming a body called acet amide. These facts are 
 shown by structural formulas: 
 
 HO HO 
 
 H | || | || H 
 
 > N C C O H H C C N < 
 
 H| I H 
 
 H H 
 
 Amidoacetic acid Acetamide 
 
 Urea, carbonyl diamide, (NH 2 ) 2 CO, is the most abun- 
 dant solid ingredient of normal human urine. It is a color- 
 less solid, crystallising readily and is freely soluble in water 
 and alcohol. Most of its salts are also soluble, but the 
 nitrate and oxalate are but sparingly so, hence the ad- 
 dition of nitric or oxalic acid to urines rich in urea will 
 produce a precipitate. Urea is strictly a diamide, that 
 is, formed by the substitution of an acid radicle the 
 group CO but this overcomes only one of the amidogen 
 groups, hence urea forms salts with one equivalent of 
 acid, not as do the diamines with two equivalents. As 
 with all other compounds of these types, the whole mole- 
 
172 ORGANIC CHEMISTRY. 
 
 cule of the acid acts; urea hydrochloride is CH 4 N 2 O,HC1. 
 The following structural formulas will show the relation of 
 urea to carbonic acid through the intermediate body, 
 carbamic acid: 
 
 o 
 
 H-0 || 
 
 H O >C=0 C 
 
 >C=O H N A 
 
 H O I H N N H 
 
 H I | 
 
 H H 
 
 Carbonic acid Carbamic acid Urea 
 
 Urea is not liable to decomposition when in pure solu- 
 tion, but in presence of proteid matters and exposed to the 
 air it soon hydrolyses to ammonium carbonate. This 
 is the ordinary reaction by which urine becomes alkaline 
 on standing: 
 
 CH 4 N 2 + 2 H 2 O = (NH 4 ) 2 CO 3 
 
 This change is due to enzyms formed by microbes. 
 
 Urea is decomposed by hypochlorites and hypobromites 
 with evolution of carbon dioxide and nitrogen. This 
 reaction is utilised in the quantitative determination of 
 urea in urine. Urea can be prepared synthetically by 
 heating ammonium cyanate. This was the first discov- 
 ered instance of synthesis. The change is merely a re- 
 arrangement. (See under Cyanates.) 
 
 Experiment 60. Melt in a sand crucible of about 50 c.c. capac- 
 ity, 10 grams of commercial potassium cyanide and stir in, grad- 
 ually and slowly, 40 grams of lead monoxide (litharge). When 
 the entire amount has been added pour the mass out upon an 
 iron plate, and allow to cool. Separate as far as possible the 
 reduced lead from the potassium cyanate that has been formed; 
 powder the latter and dissolve in 50 c.c. of cold water, filtering 
 
AMMONIUM DERIVATIVES. 173 
 
 if necessary. Add a cold saturated solution of 12 grams of am- 
 monium sulphate, heat the mixture slowly on the water-bath to 
 a temperature of 60 and maintain it at that point for an hour. 
 The ammonium cyanate which is the first product of the reaction 
 is changed to urea. This may be obtained by evaporating the 
 solution to dryness in shallow basins on the water-bath and ex- 
 tracting the residue with boiling alcohol. The urea crystallises 
 from the cold alcohol. It is not quite pure but will show the 
 characteristic properties. 
 
 Many complex bodies of these types are found in the 
 fluids of living tissues and among products of putrefaction. 
 Some of these are described in the section on Purins, 
 others in the section on Ptomaines and Leucomaines. 
 Some others of considerable importance are here described. 
 
 Taurin, amidothylsulphonic acid, C 2 H 4 (NH 2 )HSO 3 , is ob- 
 tained by hydrolysis of taurocholic acid of bile, especially 
 ox bile, by hydrochloric acid, forming taurin and cholic 
 acid. Taurin forms colorless crystals very soluble in 
 water. As it contains NH 2 and HSO 3 it has both acid 
 and basic properties. 
 
 Amidoacetic acid, glycocoll, glycin, HC 2 H 2 (NH 2 )O 2 . 
 This may be obtained by several methods, among which 
 are boiling glue with sulphuric acid, warming monochlor- 
 acetic acid with dry ammonium carbonate, and decom- 
 position of glycocholic acid (of bile) by potassium hydrox- 
 ide. Amidoacetic acid is a crystalline solid, soluble in 
 water; the solution has a sweetish taste. It is both an 
 acid and a base. It easily forms salts with ordinary posi- 
 tives and also combines with common acids forming, 
 for example, the following compounds: CuC 2 H 4 NO 2 and 
 C 2 H 5 NO 2 HC1, both of which are crystalline bodies. 
 
 Amidoacetic acid forms esters with the alkyl radicles 
 and also amine derivatives of which the following will 
 serve as examples: 
 
174 ORGANIC CHEMISTRY. 
 
 Ethyl amidoacetate , C 2 H 5 C 2 H 4 NO 2 . This is a volatile 
 liquid with an odor resembling that of cacao. 
 
 Methylamidoacetic acid, HC 2 H 2 NH(CH 3 )O 2 , methyl glyco- 
 coll, sarkosin, was first obtained as a decomposition pro- 
 duct of kreatin. 
 
 HHO HH HHO 
 
 I I II V I I II 
 
 N C C O C N C C O H 
 
 H H H H C H 
 
 Methyl amidoacetate Methylamidoacetic acid 
 
 (Sarkosin) 
 
 Hippuric acid, benzoyl glycocoll. The structural formula 
 of this shows that it contains residues of both amidoacetic 
 acid and benzoic acid; in fact, its empirical formula may 
 be obtained by adding the formulas of these acids and 
 deducting H 2 O. By hydrolysis and also by the action of 
 acids or alkalies, hippuric acid may be decomposed into 
 benzoic acid and amidoacetic acid. As hippuric acid 
 occurs in considerable proportion in the urine of herbiv- 
 orous animals, it has been a commercial source of ben- 
 zoic acid. 
 
 O=C O H 
 
 Hippuric acid. 
 
AMMONIUM DERIVATIVES. 175 
 
 Trimethyl glycocoll is betaine, a ptomaine described in 
 another section. 
 
 Amido-derivatives of the higher acids exhibit numerous 
 instances of isomerism. Among these are: 
 
 Leucins. Under the name leucins several analogous 
 substances with the empirical formula, C 6 H 13 NO 2 , have 
 been included. They are found among the products of 
 digestion of proteids, especially under the influence of 
 trypsin, and are often associated with tyrosin. 
 
 One form of leucin, probably an amidocaproic acid, is 
 derived from casein and has also been prepared synthet- 
 ically; another form is a derivative of butylacetic acid. 
 Some of these forms contain asymmetric carbon and are, 
 therefore, optically active. 
 
 Tyrosin, 1-4 phenolamidopropionic acid. This is pro- 
 duced in many transformations of proteid matters, such as 
 boiling horn, hair or albumin with sulphuric acid, digesting 
 proteids for some time with pancreatic secretion and by 
 putrefactive actions. It has been prepared synthetically. 
 
 HO 
 
 H C H 
 i 
 
 ,H 
 
 H C 
 
 I 
 O=C O H 
 
 Tyrosin 
 
 Cystin, C 6 H 12 N 2 O 4 S 2 , probably an amidothiolactic acid 
 derivative occurs as a crystalline sediment in human 
 urine and sometimes forms a calculus. 
 
 Asparagin is an example of the presence of amidogen 
 
176 ORGANIC CHEMISTRY. 
 
 in two positions in a molecule. It is succinic acid with one 
 hydroxyl group replaced by amidogen, and another amido- 
 gen group replacing a hydrogen atom attached to carbon 
 so that both the amine and amide structures are exhibited. 
 Asparagin has asymmetric carbon. It is found in the seeds 
 of many plants and in the sprouts of asparagus and vetch. 
 The asparagin in asparagus is levorotatory; that in vetch 
 is mostly the same, but the dextrorotatory form also is 
 found. The natural occurrence of a levorotatory body 
 in predominating quantity is unusual, since most natural 
 bodies that are optically active are dextrorotatory. 
 
 H H 
 
 v 
 
 O N H O H 
 
 II I I II I 
 C C C C N 
 
 O H H 
 
 H 
 
 Amido-succinamic acid 
 (Asparagin) 
 
 Purins, Alkaloids, Ptomaines, Leucomaines . These are 
 groups of nitrogenous compounds many of which are 
 amines or amides. The important bodies of each type 
 are described in connection with the group named. 
 
 Azo-, DIAZO- AND HYDRAZO-COMPOUNDS. 
 
 When two atoms of nitrogen are joined by two bonds, 
 and the remaining bonds are joined to similar radicles, 
 a group is formed called an azo-compound. When the 
 
AZO-, DIAZO- AND HYDRAZO-COMPOUNDS. 177 
 
 radicles are dissimilar, a diazo-cornpound (diazonium) 
 is formed. When an atom of oxygen is inserted between 
 the nitrogen atoms, an azoxy-compound is formed. When 
 one bond of each nitrogen atom is united to an atom of 
 hydrogen, the body is called a hydrazo-compound. These 
 points are exemplified in the following formula: 
 
 = N N= _N=zN 9 
 
 N-N 
 
 Hydrazo- group Azo- group Azoxy- group 
 
 HN NH 2 HN - NH 
 
 Diazobenzene Phenylhydrazin Hydrazobenzene 
 
 (diazonium) sulphate 
 
 Hydrazins. The hydrazins agree with the diazo- 
 compounds in containing dissimilar radicles, but differ 
 in the fact that the union between the nitrogen is by one 
 bond only. 
 
 The difference is shown in the following formulas : 
 
 Diazo-benzene nitrate. Phenylhydrazin nitrate. 
 
 C 6 H 5 N = N (NO,) C 6 H 5 N N(N0 3 ) 
 
 H H 3 
 
 Azo-compounds are now of considerable practical 
 importance. Many of them are brilliant in color and less 
 liable to fade than some of the other forms of synthetic 
 colors. Some of them have the valuable property of dyeing 
 cotton without a mordant. A few are quite insoluble 
 in water but soluble in oil. 
 
178 ORGANIC CHEMISTRY. 
 
 Azo- derivatives are usually produced through the 
 intermediate development of diazo-compounds, by reac- 
 tion of amine derivatives with nitrous acid. This method 
 called "diazotising," was discovered by Griess. It is 
 regularly used in manufacturing operations, the nitrous 
 acid being obtained by the action of a strong acid, acetic, 
 sulphuric or hydrochloric, on sodium nitrite. 
 
 A few of the azo- colors are insoluble in water but soluble 
 in alcohol and in oils. They are used for coloring fatty 
 foods, especially butter and butter-substitutes. Several 
 of them have been designated by the fanciful term Soudan, 
 and distinguished by appended letters, as noted in the 
 general description of synthetic colors. 
 
 Soudan I istoetanaphtholazobenzene, C 6 H 5 N= NC 10 H 6 OH. 
 
 These derivatives are capable of "sulphonation," that 
 is, conversion into sulphonic acids by treatment with 
 sulphuric acid. By this means many of them are ren- 
 dered more soluble and, apparently, in a few instances, less 
 toxic. From the sulphonic acids salts may be formed with 
 any of the metals, and thus derivatives analogous to the 
 mineral salts are obtained. 
 
 Methyl orange, helianthin, Porrier's tropeolin D, Orange 
 III, gold orange, mandarin orange. Sodium dimethyl 14 
 amido-azobenzenesulphonate. This series of commercial 
 synonyms is given merely as an instance of the nomen- 
 clature of these bodies. Methyl orange is the ordinary 
 name. Its composition is seen from the structural for- 
 mula, but obviously other positive elements can replace 
 sodium, giving derivatives of the same type but slightly 
 different in properties. Methyl orange dyes bright orange. 
 It is used in coloring textiles and sometimes in foods, 
 and has a special use as an indicator in acidimetry and 
 alkalimetry. It is an orange-yellow powder, freely soluble 
 
AZO-, DIAZO- AND HYDRAZO-COMPOUNDS. 179 
 
 in water, producing a yellow solution which becomes red- 
 orange by addition of any mineral acid. 
 
 N= =N 
 
 NaSO 3 N(CH 3 ) 2 
 Methyl orange 
 
 Bismarck brown is the hydrochloride of a complex azo- 
 derivative. It is used for coloring imitation wines, fruit 
 juices and in confectionery, as well as in dyeing textiles. 
 
 Congo Red. This color belongs to a group termed 
 " tetrazo-compounds " because they contain the azo- 
 group twice. The term diazo is appropriated to a special 
 form of azo-compounds. The tetrazo-compounds are 
 chiefly interesting to dyers, but Congo red, the structural 
 formula of which is here shown, is used in the laboratory 
 as an indicator, having the striking property of assuming 
 colors the reverse of litmus and other common vegetable 
 colors. Congo ' red is blue in acid solution and red in 
 alkaline. It is not a very delicate indicator, but is much 
 used in testing stomach-contents for free hydrochloric 
 acid. It dissolves in water. It is used generally in the 
 form of test-papers. 
 
 NH, NaSO 3 
 
 =N< \/ \N=N 
 
 NaSO, " ' NH, 
 
 Congo red 
 
 The addition of a strong acid liberates the free sulphonic 
 acid which is blue, but its salts are red. 
 
l8o ORGANIC CHEMISTRY. 
 
 DIAZO-COMPOUNDS. As previously noted, this term is 
 applied when the nitrogen atoms are united by more than 
 one bond and the residual bonds are not in union with the 
 same type of radicle. The exact nature of the molecular 
 structure has been disputed among chemists. Present 
 opinion tends to regard them as more closely analogous 
 to ammonium than to amine, and hence they are often 
 termed "diazonium" compounds. The difference between 
 these views is shown in the formulas for diazobenzene 
 chloride : 
 
 Amine type. Ammonium type. 
 
 C 6 H 5 N = N Cl C 6 H 5 N Cl 
 
 N 
 
 These compounds are generally unstable. Many of them 
 are explosive and some highly poisonous. It has been 
 thought that some are formed in the putrefaction of pro- 
 teids, especially milk-proteids, and that this accounts for 
 the violently poisonous properties of some spoiled foods. 
 They do not appear to be present in advanced states of 
 putrefaction, but when the food is merely stale. As they 
 are mostly easily decomposed by heat, cooking of such 
 food often takes away the poisonous action. In the com- 
 mon cases of cheese and ice-cream poisoning, diazo-ben- 
 zene (diazonium) salts have been supposed to be present, 
 and one, provisionally termed " tyrotoxicon " (Gr. cheese- 
 poison), may be diazobenzene butyrate (diazonium buty- 
 
 O N=N 
 
 C 3 H 7 
 
 Diazobenzene butyrate 
 (Tyrotoxicon) 
 
AZO-, DIAZO- AND HYDRAZO-COMPOUNDS. l8l 
 
 rate), the structural formula of which is annexed, but the 
 products will differ with different conditions. The small 
 amounts in which the bodies are produced and the ease 
 with which they are decomposed, makes identification of 
 them uncertain. 
 
 The hydroxides of the group are unstable but they form 
 derivatives analogous to sodium ethylate which are not so 
 easily decomposed. For example, a potassium compound 
 of the empirical formula, C 6 H 5 N 2 OK, is known. Esters have 
 also been prepared. These bodies have as yet little 
 practical importance, but it is not improbable that use- 
 ful high explosives may be prepared from some members 
 of the group. 
 
 Experiment 61. Prepare the following solutions. The pro- 
 portions given are suggestive only; it is not necessary to adhere 
 strictly to them: 
 
 0.05 gram phloroglucol in 5 c.c. alcohol; 
 
 0.05 gram vanillin in 5 c.c. alcohol; 
 
 o.i gram sulphanilic acid in 10 c.c. of water and 5 c.c. hydro- 
 chloric acid; 
 
 o.i gram alphaamidonaphthalene in 10 c.c. of water and 5 c.c. 
 hydrochloric acid; 
 
 o.i gram sodium nitrite in 10 c.c. of water; 
 
 o.i gram betamidonaphthalene in 10 c.c. of water and 5 c.c. 
 of hydrochloric acid. 
 
 The solution of sulphanilic acid and amidonaphthalenes may 
 be slow. It will not be necessary to wait until all the material is 
 dissolved. Care should be taken not to get the alphaamidonaph- 
 thalene on the hands, as it has a persistent, disgusting odor. 
 The sodium nitrite solution should be fresh. The others keep 
 well. 
 
 Experiment 62. To 10 c.c. of water add i drop of the sodium 
 nitrite solution and then about i c.c. each of the solutions of 
 sulphanilic acid and alphaamidonaphthalene. A pink tint will 
 soon appear and deepen in about ten minutes. 
 
 Experiment 63. Repeat Experiment 62, using no sodium 
 nitrite. No color will appear. 
 
182 ORGANIC CHEMISTRY. 
 
 The changes that occur in Experiment 62 are as follows: 
 NH, 
 
 + HNO 2 = 
 HS0 3 S0 3 
 
 1-4 amidobenzenesul- Diazobenzenesulphonic 
 
 phonic acid anhydride 
 
 (Sulphanilic acid) 
 
 The diazo-compound reacts with the amidonaphthalene 
 to produce the azo-derivative as follows: 
 
 C 6 H 4 N=NS0 3 + C 10 H 7 NH 2 = C 10 H 6 (NH 2 )N =NC 6 H 4 HSO 3 
 
 Alpha-azo-amidonaphthaleneparazo- 
 benzenesulphonic acid 
 
 The above reactions are analogous to those occurring 
 in a urine test now much used under the name "Ehrlich's 
 diazo-reaction." This depends on the formation of a red 
 azo-derivative by the reaction of the diazo-compound 
 produced in the above manner with bodies not yet iso- 
 lated, occurring in urine in some diseases. The test is 
 made by adding to the urine solutions of sodium nitrite 
 and sulphanilic acid when, if the pathologic condition 
 exists, a red color is produced. 
 
 The reaction is also used for the detection of nitrites 
 in water. In this case the sulphanilic acid and amido- 
 naphthalene are added in acid solution to a sample of the 
 water. If nitrite is present the color is soon produced. 
 No reaction occurs with nitrates. The test is very deli- 
 cate; i part of nitrogen as nitrite in 1,000,000,000 parts of 
 water can be easily detected, using only about 5 c.c. of 
 the sample. 
 
 Experiment 64. Repeat Experiment 62, substituting betamido- 
 naphthalene for the alpha-form. A pale yellow color will be 
 
AZO-, DIAZO-" AND ~HYDRAZO-COMPOUNDS. 183 
 
 developed. By the comparison of these experiments it will be 
 seen that a slight difference in arrangement of atoms may produce 
 great difference in properties. The two amidonaphthalenes are 
 close stereo-isomers, yet they give markedly different azo-deriva- 
 tives. 
 
 Experiment 65. Repeat Experiment 62, substituting for the 
 naphthalene derivative, weak solutions of the following sub- 
 stances: phenol, aniline, vanillin, coumarin, alphanaphthol, beta- 
 naphthol, each as a separate test. 
 
 Experiment 66. Add a few drops of hydrochloric acid to 
 i c.c. of the phloroglucol solution and with this mixture make 
 tests of the following substances, but touching them with rods 
 dipped in the mixture: cotton, linen, fine writing paper, common 
 printing paper (newspaper). If any of these materials contain 
 raw wood fiber, a bright red color will be quickly developed at the 
 point at which the liquid is applied. Common newspaper contains 
 about 80 per cent, ground wood and shows the color strongly. 
 Cotton, linen and high-class writing paper being pure cellulose do 
 not give any color. 
 
 If ground olive stones, almond shells or other materials contain- 
 ing the so-called "stone-cells" be tested with this solution the 
 color will also be obtained, and by examining the powder under 
 a power of about 100 the stained cells will show clearly. 
 
 HYDRAZINS. In these the nitrogen atoms are united 
 by a single bond. They are therefore structurally more 
 like the diamines than are the azo-derivatives. The 
 important member is phenylhydrazin, C 6 H 5 HN NH 2 on 
 account of its reactions with ketones and aldehydes. 
 
 Phenylhydrazin hydrochloride. This substance is now 
 largely used as a test for sugar. It is a fawn-colored, 
 crystalline powder with an odor recalling that of the 
 geranium. It irritates the skin, producing in some persons 
 an annoying eruption. It is liable to decomposition, 
 becoming dark and pasty and of offensive odor. It 
 should not be used in experiments or tests unless it 
 is in good condition. Phenylhydrazin hydrochloride 
 
184 ORGANIC CHEMISTRY. 
 
 forms with ketonic and aldehydic bodies characteristic 
 compounds, insoluble in water, termed "osazones" The 
 osazones are obtained in several ways. A common 
 method is to heat the carbohydrate, phenylhydrazin 
 compound and sodium acetate for some time in boiling 
 water when the osazone separates. 
 
 Dextrose and levulose yield the same osazone, as mole- 
 cules of the hydrazin group attach themselves to the two 
 terminal carbon atoms breaking up, therefore, the alde- 
 hydic and ketonic structures which are, respectively, 
 characteristic of the two bodies. 
 
 Lactose and maltose yield osazones; sucrose does not. 
 
 Experiment 67. Dissolve 0.5 gram ordinary glucose in 10 c.c. of 
 water in a testtube, add i gram of sodium acetate and 0.5 gram 
 of phenylhydrazin hydrochloride. The proportions need not be 
 followed strictly but should be approximately as given. The 
 phenylhydrazin should not be allowed to come in contact with the 
 skin as it may irritate it severely. Immerse the mixture in boiling 
 water for fifteen or twenty minutes. A yellow crystalline deposit 
 of phenylglucosazone will form. This should be examined under 
 a power of about 40 or 50 when the stellate crystals will be seen. 
 
 Experiment 68. Repeat the above experiment using the sub- 
 stances separately and note the differences: 0.5 gram sucrose; 
 0.5 gram lactose; 0.5 gram starch. Only lactose forms a pre- 
 cipitate, but commercial sucrose may contain impurities, and 
 yield a slight deposit of the glucosazone. 
 
 Experiment 69. Test a portion of the furfural distillate, ob- 
 tained in Experiment 54, by heating it with a few drops of acetic 
 acid and a small amount of phenylhydrazin hydrochloride. Fur- 
 furosazone will be formed. 
 
 If a small quantity of phenylhydrazin hydrochloride be added to 
 a weak solution of formaldehyde, then a few drops of a fresh solu- 
 tion of sodium nitroprusside, and then a little sodium hydroxide 
 solution, a deep blue liquid is formed. This is a delicate and use- 
 ful test for formaldehyde. With milk, the color is greenish. 
 
ALKALOIDS. 
 
 The natural bases or alkaloids are so called because they 
 possess the power of neutralising acids, with which they 
 form distinct and cry stallis able compounds. They may 
 be divided into two classes: (T) Non-volatile alkaloids 
 consisting of C, H, N and O. These are solids, usually 
 crystallisable, sometimes possessing a definite melting 
 point and often capable of sublimation, though generally 
 with partial decomposition. (2) Volatile alkaloids, con- 
 sisting of C, H and N. These are liquids capable of partial 
 vaporisation at ordinary temperatures, and usually having 
 very high boiling points. The salts of the volatile alka- 
 loids are non-volatile, crystallisable solids. 
 
 The alkaloids bear a close resemblance to the sub- 
 stitution amines, but they are more complex in constitu- 
 tion, especially as regards the presence of oxygen, which is 
 not contained in the common substitution amines. 
 
 As regards the general properties of the non-volatile 
 alkaloids, they are solids, almost insoluble in water to 
 which they impart an alkaline reaction. They are usually 
 soluble in alcohol, from which they "may be readily crystal- 
 lised. They are mostly soluble in one or more of the 
 immiscible solvents, such as chloroform, ether, petroleum 
 spirit, benzene and amyl alcohol, in which solvents, how- 
 ever, their salts are insoluble; the salts are almost in- 
 variably soluble in water. This difference in the solubili- 
 ties of the alkaloids and their salts is utilised for their 
 separation and purification. Separation by immiscible 
 
 185 
 
186 
 
 ORGANIC CHEMISTRY. 
 
ALKALOIDS. 
 
 187 
 
 owerfully toxic. 
 
 r sed as an antiseptic, 
 powerful oxytoxic. 
 
 3 
 
 1 
 
 G 
 
 _ 3 IT 
 
 .2 
 
 'ed 
 
 22 G 
 
 ^ S ~* 
 o o c 
 >">- 
 <; 
 
 C/2 i- 
 
 .d 
 
 OJ 
 
 bX) 
 O 
 
 5 *-! 
 
 1 ^ 
 
 phoretic. 
 tenicide. 
 
 powerful myotic. 
 
 
 
 
 
 ft 
 
 P < 
 
 > 
 
 <! & Q 
 
 <^ hJ 
 
 ^ 
 
 <; 
 
 < 
 
 
 
 
 
 t * 
 
 H 5 
 
 K^ 3^ 
 ^ ^ 
 
 5 f 
 
 55 On 
 ^ ^ 
 
 Vi 
 
 1 s 
 
 2- s 
 
 oj 
 (j * cti 
 
 o -I i '* 
 
 X * 
 
 & Sri 
 v * 
 
 V *&'9m*~*j. ^ 
 
 Golden Seal {Hydrastis canadensis). 
 Hydrastine. 
 
 rt 
 
 G 
 oj 
 >_i 
 OS 
 3 
 bJO 
 
 of 
 
 "o 
 
 ^ 
 oJ 
 
 iS 
 
 
 
 g 
 
 of 
 
 
 
 Coca {Erythroxylon Coca). 
 Cacao {Theobroma Cacao). 
 With Theobromine. 
 
 Aconite (Aconitum Napellus). 
 Sabadilla (Asagrcea officinalis^). 
 
 Colchicum ( Colchicum autumnale). 
 Jaborandi (Pilocarpus Jabor- 
 
 ^^^// ) . 
 Pomegranate (Punica Granatuni). 
 
 Calabar bean (Physostigma ven- 
 enosum ) . 
 
 Yellow Jasmine ( Gelsemium sem- 
 
 pervirens) . 
 
 Ipecac ( Cephaelis Ipecacuanha) . 
 Bloodroot {Sanguinaria canaden- 
 
 ^J"). 
 
 Hydrastis canadensis. 
 
 00 
 
 ^^ 
 
 00 
 
 cT 
 
 if - ' 
 
 <So 
 
 ?: 
 
 
 ^ M 
 
 *I 
 
 cr 
 
 
 ik 
 
 o* 
 
 ^^i 
 
 ^H^H 
 
 ffi 
 
 ^tCC DC 
 
 ^0^ 
 
 **"jf**x 
 
 W 
 
 a 
 
 ^ 
 
 
 ^0^0 
 
 s 
 
 UCJ 
 
 CJ CJ 
 
 u 
 
 CJOCJ 
 
 CJCJ 
 
 CJU 
 
 CJ 
 
 CJ 
 
 CJ 
 
 
 CJCJ 
 
 CJ 
 
 
 
 
 
 
 
 
 qj 
 
 
 
 
 
 
 <u 
 
 
 ' 1) (L) 
 
 
 
 
 G 
 
 
 
 <u 
 
 
 <D " 
 G 
 
 .S 
 
 G G 
 
 ^ 
 
 ' fl.3 
 
 <U D 
 
 s. 
 
 <u 
 
 G 
 
 's9 
 
 bJO.S 
 
 CD 
 
 r; 
 
 
 . G 
 
 "C 
 
 .^ ctf 
 
 <D 
 
 G <L> 
 X! S 
 
 4J J~ fl) 
 
 S 3.S 
 
 '5 
 
 J 'i! 
 
 % -S 
 
 
 IM 
 
 .22 
 
 c^ <U 
 
 1 
 
 
 o ;.; 
 
 G .2 
 
 G 
 
 |M 
 
 11 
 
 4_> >-i 
 
 in W 
 
 "S^sS 
 >* x^3 
 
 WKu 
 
 t- 
 
 'e5 o o 
 
 CJ <U OJ 
 
 CJHH 
 
 o ^ 
 
 CJ D 
 
 S 
 
 o rz 
 
 U P^H 
 
 JH 
 
 ? 
 
 PH 
 
 C/3 M 
 
 >^. V-X 
 
 
 
 <D 
 c^ 
 
 13 
 
 
 
 4-> ^ 
 
 u bo 
 
 II 
 
 <D 
 
 ^ 
 
 fS 
 
l88 ORGANIC CHEMISTRY. 
 
 solvents is the basis of most of the drug-assay processes of 
 the Pharmacopoeia. 
 
 Many alkaloids are bitter, acrid or pungent; most of 
 them have decided physiological properties and are the 
 proximate principles upon which the medicinal activities 
 of the plants containing them depend. A synopsis of 
 the formulas, sources and characteristics of the principal 
 alkaloids is given on pages 186, 187. 
 
 The alkaloids are distinguished from all other plant 
 principles by the fact that the aqueous solutions of their 
 salts are precipitated by the following reagents : potassium- 
 mercuric iodide, iodine, platinic chloride, auric chloride, 
 picric acid and tannin. They often produce characteris- 
 tic color-reactions with the inorganic acids and may be 
 identified by the concurrence of several of these tests which, 
 singly, are of little value. 
 
 The alkaloids differ from inorganic bases in forming 
 salts by direct union with the acid, not by substituting 
 the hydrogen. Thus, morphine forms with hydrochloric 
 acid the compound C 17 H 19 NO 3 HC1; it is, therefore, called 
 morphine hydrochlorate (sometimes hydrochloride), not 
 morphine chloride. This is due to the fact that the alka- 
 loids are analogous to NH 3 rather than to NH 4 , and the 
 reaction between morphine and hydrochloric acid is 
 similar to the reaction NH 3 + HC1= NH 4 C1, in which the 
 hydrogen is not replaced; in fact, the hydrogen of the 
 acid may be regarded as combining with the morphine to 
 form a new molecule, C 17 H 19 NO 3 H, analogous to ammo- 
 nium and called morphium] the compound formed would 
 be morphium chloride. 
 
 Heroine, C 17 H 17 (C 2 H 3 O 2 )NO 3 , is a diacetyl ester of mor- 
 phine obtained by synthesis. It is used as a substitute 
 for morphine. 
 
ALKALOIDS. 189 
 
 Daturine, from stramonium (Datura Stramonium), is a 
 mixture of atropine and hyoscyamine. 
 
 The classification of the alkaloids in a group based on 
 the property of forming definite salts with acids brings 
 together compounds of very different structure. More- 
 over, the basic power differs considerably in, different 
 members of the group. Strychnine, morphine and quinine, 
 for instance, form stable and definite compounds. Caf- 
 feine is a weak base, many of its salts being easily decom- 
 posed. 
 
 Several essentially different types of molecular structure 
 are exemplified in the alkaloids. 
 
 Amine type. Betaine is an example of this structure. 
 Its sources and composition are described under Pto- 
 maines. 
 
 Pyridin type. Many alkaloids are of this type, con- 
 taining either the simple pyridin ring or the duplicated 
 (quinolin) ring. When either of these is present, the 
 molecular structure is stable and the substance resists the 
 action of many reagents. 
 
 Purin type. This is exemplified in caffeine and theo- 
 bromine. The former is the characteristic alkaloid of tea, 
 coffee and mat6, and is present in small amount in cacao; 
 the latter is the principal alkaloid of cacao. Their struc- 
 tural formulas are given in connection with the descrip- 
 tions of the Purins. 
 
 Hydroxyl and hydrocarbon groups are often present. 
 The latter can often be oxidised by mild oxidising agents 
 to carboxyl groups, thus converting the alkaloids into 
 acids. Several alkaloids, e. g., theophyllin and conine, 
 have been obtained synthetically. Isomers of quinine 
 have also been obtained synthetically, but they have not 
 the medicinal properties of the natural alkaloid. 
 
190 
 
 ORGANIC CHEMISTRY. 
 
 The annexed structural formulas are in some respects 
 provisional but they represent atomic arrangements 
 suggested by the reactions and transformations of the 
 substances. It will be seen that morphine contains the 
 phenanthrene ring and no pyridin. It is more easily de- 
 composed than some other alkaloids. Cocaine and ber- 
 berine contain the benzene ring; the former contains 
 asymmetric carbon. 
 
 H 
 H 
 V3H 
 
 H 
 
 HO 
 
 H 2 C 
 H 2 C N 
 
 Basic nitrogenous bodies occur in, and are produced by, 
 the decomposition of animal tissues. These are called 
 ptomaines and leucomaines and are sometimes referred to, 
 respectively, as the cadaveric or animal alkaloids. They 
 are described below. 
 
ALKALOIDS. igi 
 
 Many artificial alkaloids or allied compounds have 
 attained prominence in therapeutics during recent years. 
 Some of these possess the specific power of reducing the 
 animal temperature, and are collectively known as 
 antipyretics. They are sometimes called the "coal-tar 
 synthetics" in recognition of their origin. They are 
 generally known by trade-names which may be either 
 abbreviations of their systematic names or purely arbi- 
 trary. The following are the more important of these: 
 
 Acetanilid, antifebrin, C 6 H 5 NH(C 2 H 3 O). This is ob- 
 tained by the reaction of aniline with acetic anhydride. 
 It forms colorless and odorless crystals, soluble in 200 parts 
 of cold water, much more freely in boiling water, alcohol, 
 ether and chloroform. It is used as an antiseptic dressing 
 and internally as an antipyretic. It is the basis of several 
 proprietary antipyretics and is usually present in so- 
 called "headache powders." 
 
 Antipyrin, phenazone, phenyldimethylpyrazolon, C U H 12 - 
 N 2 O. This is prepared by the action of phenylhydrazin 
 on ethyl acetoacetate. It forms colorless crystals, freely 
 soluble in water, alcohol and chloroform. 
 
 Phenacetin, acetphenetidin, C 6 H 4 (NHCH 3 CO)OC 6 H 5 . 
 This is prepared by the action of glacial acetic acid on 
 paraphenetidin. It forms colorless crystals slightly sol- 
 uble in cold water, alcohol, ether and chloroform. 
 
ORGANIC CHEMISTRY. 
 
 O 
 
 C CH 3 
 I 
 CH, 
 
 Methyl acetanilid Phenacetin 
 
 (Exalgin) 
 
 Experiment 70. Dissolve o.i gram of quinine sulphate in 10 
 c.c. of water. Add two drops of bromine water and afterward an 
 excess of ammonium hydroxide. The liquid will assume a bright 
 emerald-green color. This is known as the thalleioquin reaction 
 and will also be given by quinidine or its salts. 
 
 Experiment 71. Dissolve .02 gram of morphine sulphate in 
 2 c.c. of water and add several drops of solution of ferric chloride. 
 A blue color will be produced which is destroyed by heating. 
 
 Experiment 72. Add a small quantity of morphine or one of 
 its salts to a drop of nitric acid upon a porcelain surface. An 
 orange-red color will be produced which rapidly fades. 
 
 Experiment 73. Dissolve .01 gram of strychnine in about 5 c.c. 
 of water and transfer the solution to a small separatory funnel. 
 Add about 2 c.c. of chloroform and then render the aqueous liquid 
 alkaline with sodium carbonate. Upon shaking the separatory 
 funnel the liberated alkaloid enters into solution in the chloroform, 
 which may be drawn off, evaporated, and the residue tested as 
 under Experiment 74. 
 
 Experiment 74. Dissolve a minute quantity of strychnine, or 
 one of its salts, in a few drops of concentrated sulphuric acid on 
 a white porcelain or glass surface, and add a small crystal of potas- 
 sium dichromate. Upon stirring the crystal of dichromate around 
 with a glass rod a blue color will be at first produced, which changes 
 to purplish blue and gradually fades through red to yellow. Ceroso- 
 ceric oxide, manganese dioxide or similar oxidising agents will 
 produce the same effect as potassium dichromate. 
 
 Experiment 75. Rub together 4 parts of hydrastine and i part 
 of morphine and treat a minute quantity as in Experiment 74. A 
 
PTOMAINES AND LEUCOMAINES. 193 
 
 color similar to the strychnine will be produced, which does not 
 fade out as rapidly but is more permanent. Tests with morphine 
 and hydrastine separately will fail to show any color. 
 
 Experiment 76. Heat a small quantity of atropine with several 
 c.c. of sulphuric acid. A peculiar aromatic odor is evolved re- 
 calling a mixture of rose and orange flower. Add a small frag- 
 ment of potassium dichromate and the odor will change to that of 
 bitter almond oil. 
 
 Experiment 77. Add a small amount of colchicine to a drop of 
 nitric acid on a white porcelain or glass surface. A blue color will 
 be produced which fades in a short time. 
 
 Experiment 78. Rub a small quantity of veratrine with a few 
 drops of sulphuric acid on a white porcelain or glass surface and 
 observe the intense red color which is produced, which does not 
 fade even after several hours. 
 
 Experiment 79. Dissolve a small quantity of caffeine in a few 
 drops of hydrochloric acid, add a few small crystals of potassium 
 chlorate and heat over a water bath until a dry residue remains. 
 Expose the residue to the vapor of ammonium hydroxide and 
 observe the characteristic rich purple color which it assumes. 
 This is known as the murexid test. Uric acid will give the same 
 reaction, being closely analogous in structure to caffeine. 
 
 PTOMAINES AND LEUCOMAINES. 
 
 The chemical changes classed under the terms fermen- 
 tation and putrefaction are caused by living organisms, 
 mostly very minute, and included under the general title 
 "microbes." It seems probable that all such transfor- 
 mations are due to enzyms. The principal action is the 
 breaking down of complex nitrogenous ingredients of the 
 living tissues, often by hydrolysis, but also by other types 
 of action, especially oxidation when the action occurs in the 
 presence of air. It follows, therefore, that if air be ex- 
 cluded, the chemical changes will be somewhat different, 
 and hence a distinction is made between the usual (aerobic) 
 decompositions and those that occur out of contact with 
 13 
 
194 ORGANIC CHEMISTRY. 
 
 free oxygen (anaerobic). The latter class has not been as 
 yet extensively studied. 
 
 The products of aerobic fermentation and putrefaction 
 have been of late studied with great zeal. Many of them 
 are distinctly basic resembling the alkaloids. Further- 
 more, the normal pathologic processes of animals give rise 
 to basic bodies. It is hardly necessary to distinguish 
 these different classes, but such distinction has been made. 
 The basic bodies produced by microbes are called "pto- 
 maines," those produced in animals, "leucomaines" 
 The latter term is not much used. Care must be taken 
 not to confuse the products of animal tissues (leucomaines) 
 with the products of microbes inhabiting the tissues, 
 fluids or cavities of animals. The latter are ptomaines, 
 for they are the result of fermentation or putrefaction 
 apart from the vital action of the animal. As such result- 
 ing bodies cause disease by absorption into the fluids of the 
 animal they are sometimes termed ''toxins." By special 
 methods, bodies (antitoxins) antagonistic in physiologic 
 effect can be obtained and used in the treatment of diseases 
 caused by toxins. 
 
 Microorganisms either directly or by intermediate action 
 of enzyms, may produce alcohols, acids, neutral substances, 
 cyclic compounds and nitrogenous derivatives; in fact, 
 representatives of any class of organic compounds. The 
 term ptomaine is derived from a Greek word meaning a 
 dead body, and following out the analogy we might apply 
 the same term to all the products of the decomposition of 
 organic bodies under the influence of microorganisms, 
 distinguishing the different classes by the proper ter- 
 minations. Thus ptomols would be alcohols, produced 
 by such action. Lactic and butyric acids are ordinarily 
 produced by the action of microbes and are therefore 
 ptomic acids. 
 
PTOMAINES AND LEUCOMAINES. 195 
 
 It is to be noted, therefore, that the ptomaines are 
 not peculiar as a class among basic organic bodies, nor 
 are they the only products of decompositions. 
 
 All ptomaines contain nitrogen, but the relation of 
 this to the other atoms is dependent on the nature of the 
 original molecule and the microbes or enzyms which 
 bring about the transformation. Of the different types 
 of combination that nitrogen may exhibit, amido-, azo- and 
 diazo-groups are the most common. Pyridin compounds 
 are not usual among the products of ordinary putrefaction ; 
 nitro- and nitroso-groupings are never observed. 
 
 The amines observed range in complexity from true 
 basic monamines to tetramides with acid function. 
 
 Of the simpler type are some common ptomaines, such 
 as putrescine, N 2 H 4 (CH 2 ) 4 , tetramethene diamine, and 
 cadaverine, (NH 2 )(CH 2 ) 5 , pentamethenedia'mine. A syn- 
 thetic product used in medicine is also of analogous struc- 
 ture, piperazin, diethenediamine, N 2 H 4 (C 2 H 4 ) 2 . Similar 
 but more complicated bodies are indicated in the annexed 
 structural formulas. They are of the general type of the 
 true bases and it will be seen that alcoholic and acid 
 groupings are also represented. 
 
 H 3 C H H H 3 C H H 
 
 N 
 
 Li I I I -n-s I 
 
 O H H O 
 
 i.;: : : i 
 
 Choline Neurine 
 
 Choline. Salts of this base occur in many animal and 
 vegetable tissues. It was originally extracted from bile 
 
196 ORGANIC CHEMISTRY. 
 
 to which the name refers. Its glycerophosphate exists in 
 lecithins. As will be seen from the structural formula 
 it is a complex derivative of ammonium hydroxide. It is 
 strongly alkaline, absorbing water and carbon dioxide 
 from the air. It forms a crystalline chloroplatinate. 
 
 Neurine. This is obtained by boiling choline with 
 barium hydroxide and is produced in some putrefactions. 
 
 Muscarine occurs associated with choline in poisonous 
 mushrooms. 
 
 Betaine occurs in the sugar beet and is also produced 
 by the cautious oxidation of choline. 
 
 H 3 C H H H 3 C 
 
 C C O H | 
 
 I Ais^- 
 
 * H A H 
 
 H H 
 
 Muscarine Betaine 
 
 PURINS. Alloocuric bodies, Xanthin bases. Under these 
 terms, the first being now much in vogue, is included a 
 number of bodies of complex structure which it has been 
 proposed to regard as derived from a hypothetical radicle 
 termed the "purin nucleus." From this, by association 
 with other radicles, such as amidogen, imidogen, hydroxyl 
 and carbonyl, formulas of the members of the series may 
 be obtained. The following formulas show the relations 
 of some of the members of the series to the purin nucleus 
 and to purin itself: 
 
 N=C N=CH 
 
 C C N HC C-NH 
 
 II II \ II \ 
 
 N_C-N=C N-C N=C 
 
 Purin nucleus Purin 
 
PTOMAINES AND LEUCOMAINES. IQ7 
 
 It will be seen that purin is, in a measure, a duplicated 
 urea, the oxygen being absent and part of the hydrogen 
 replaced by carbon. The purin bodies are at present 
 attracting much attention owing to their supposed relation 
 to animal nutrition and metabolism. They exist in 
 many foods and abundantly in tea, coffee, mate and cacao. 
 
 The following table gives the empirical formulas of 
 some members of this group, and a few structural for- 
 mulas are annexed: 
 
 Uric acid C 5 H 4 N 4 O 3 
 
 Xanthin C 5 H 4 N 4 O 2 
 
 Hypoxanthin C 5 H 4 N 4 O 
 
 Paraxanthin C 7 H 8 N 4 O 2 
 
 Theobromine C 7 H 8 N 4 O 2 
 
 Caffeine C 8 H 10 N 4 O 2 
 
 Adenine Q>H 5 N 5 
 
 H N C H H 3 C N C H 
 
 I II I II 
 
 = C C N H = C C N CH 3 
 
 I I \ I I \ 
 
 H N C=N C H N C=N C 
 
 II II 
 
 o o 
 
 Xanthin Theobromine 
 
 H N C=O H 3 C N C H 
 
 II I II 
 
 = C C N H O=C C N CH 3 
 
 I II \ I I \ 
 
 H N C N C=0 H 3 C N C=N C=O 
 
 A 
 
 Uric acid Caffeine 
 
IQ8 ORGANIC CHEMISTRY. 
 
 Of these bodies caffeine and theobromine are described 
 in connection with the group of alkaloids in which they 
 are usually classified, but they possess only feebly basic 
 properties, and their formulas are structurally very 
 different from those in the majority of that group. 
 
 Uric acid, trioxypurin, C 5 H 4 N 4 O 3 . This occurs in small 
 amount in the urine of mammals and abundantly in that 
 of birds and reptiles. It can be obtained by strongly 
 acidulating urine with hydrochloric acid and allowing the 
 mixture to stand for some hours. Uric acid separates 
 as a crystalline precipitate, usually brownish, from ad- 
 herent coloring matter. When pure it is in colorless 
 crystals, almost insoluble in cold water and only slightly 
 soluble in boiling water. It forms several derivatives with 
 sodium, potassium and ammonium, usually called ' ' urates, ' ' 
 which are more soluble in water than the acid itself. 
 Uric acid does not contain the carboxyl radicle, but the 
 group HNCO, which occurs thrice in the molecule, confers 
 nominal acidity. 
 
 Xanthin, dioxypurin, C 5 H 4 N 4 O 2 . This occurs in small 
 amount in urine, but is more abundant in flesh juice, hence 
 is found in commercial meat-extract. It is colorless, 
 crystalline and nearly insoluble in cold water. It is 
 dissolved by alkaline solutions. 
 
 Hypoxanthin, oxypurin, C 5 H 4 N 4 O 2 . This is found as- 
 sociated with xanthin. It is crystalline and but slightly 
 soluble in cold water. 
 
 Paraxanthin, dimethylxanthin, C 7 H 8 N 4 O 2 , is isomeric 
 with theobromine. 
 
 Adenine, amidopurin, C 5 H 5 N 5 . This occurs in several 
 animal fluids, but is most abundant in tea-leaves. It 
 contains no oxygen. 
 
 Purin bodies are without nutritive value to the higher 
 
PTOMAINES AND LEUCOMAINES. IQQ 
 
 animals, hence any that are present in the food are passed 
 off as promptly as possible by the excretions. The or- 
 dinary waste of tissue (destructive metabolism) in the 
 animal produces purins, hence the excretions will contain 
 both those in the food and those formed in the body. The 
 former are termed ''exogenous purins," the latter "en- 
 dogenous purins." 
 
 Many analyses of food stuffs have been made in order- 
 to determine the amount of purins, so that the diet may be 
 regulated to secure the minimum amount of exogenous 
 purins when these are especially objectionable. Meats, 
 some wines and cereals contain considerable amounts of 
 purins; milk, eggs and cheese small amounts. Compara- 
 tively few natural purins have been isolated, but over one 
 hundred derivatives have been prepared synthetically. 
 
 The endogenous purins are regarded as derived largely 
 from the nucleoproteids by successive dissociation, with 
 probably both hydrolysis and oxidation under the influ- 
 ence of enzyms. If these processes be carried to a con- 
 siderable extent, as occurs when the functions of nutrition 
 and excretion are well balanced, the purin derivatives are 
 mostly converted into a simple diamido-compound urea, 
 which constitutes the principal result of the waste of 
 nitrogenous tissues in the higher animals and is the most 
 abundant solid ingredient of normal human urine. 
 
 Urea and some closely related excretory substances are 
 described elsewhere. 
 
PROTEIDS OR ALBUMINOIDS. 
 
 Proteids or albuminoids are complex bodies that form 
 the essential portions of living tissues. They all contain 
 hydrogen, oxygen and nitrogen; most of them contain 
 also sulphur; a few contain phosphorus, and a few con- 
 tain iron. Even copper has been found in some, and it is 
 not unlikely that elements, not usually existing in natural 
 organic bodies, are present in proteids having highly 
 specialised function or developed under exceptional con- 
 ditions. 
 
 Little is known as to the structural formulas of proteids, 
 except that they are all very complex, containing open and 
 closed carbon chains. The nitrogen is probably in a 
 pyridin ring and partly in a cyanogen or amine form. 
 Some authorities distinguish between proteids and al- 
 buminoids, limiting the latter term to gelatin and closely 
 analogous bodies. Other authorities limit the term 
 proteid to substances that yield monamido-acids on de- 
 composition by certain processes. These distinctions, 
 however, can not be regarded as final, and it is sufficient 
 for present study to classify a considerable number of 
 bodies under the general terms here used, even though 
 appreciable differences in properties are noted. The 
 proper classification will be made when the rational 
 formulas become known. 
 
 Proteids are generally colorless or faintly yellow amor- 
 phous solids, soluble in water, but some require for this 
 purpose the coincident presence of certain salts. Some 
 proteids dissolve in alcohol. Water solutions putrefy 
 
PROTEIDS OR ALBUMINOIDS. 2OI 
 
 promptly, under ordinary conditions, but this is merely 
 the result of the action of microbes. In the presence 
 of antiseptics or in sterile solution proteids are practically 
 permanent. They are ordinarily eminently colloid, hence 
 have very low diffusive power, but one proteid .has been 
 obtained in a distinctly crystalline form, and there is no 
 reason to doubt that all of them are capable of crystal- 
 lising under certain conditions. Solutions of proteids have 
 marked levorotatory power, 
 
 A satisfactory classification of proteids is impossible 
 in the present imperfect state of knowledge. In many 
 cases several bodies are probably included under one name ; 
 in other cases a supposed natural proteid is a product 
 of the methods employed in obtaining it. The classi- 
 fications usually followed take but little account of vege- 
 table proteids, although these are quite numerous. The 
 following classification is that of Hammarsten; it is merely 
 an incomplete index to the animal proteids. 
 
 Simple proteids or albumins: 
 
 Albumins proper: Ovalbumin, seralbumin, lactalbumin. 
 
 Globulins: Fibrinogen, vitellin, myosin, crystallin. 
 
 Nucleoalbumin : Casein. 
 
 Albuminates : Acid albuminate, alkali albuminate. 
 
 Albumoses. 
 
 Peptones. 
 
 Coagulated proteids: Fibrin, coagulated albumins. 
 
 Compound proteids : 
 
 Hemoglobins. 
 
 Glyco-proteids : Mucins, hyalogens, amyloid. 
 Nucleoproteids : Nucleohiston, cytoglobin. 
 Albuminoids: Keratin, elastin, collagen. 
 
 Many proteids are precipitated from their solution in 
 water, in forms that are not capable of re-solution without 
 chemical change. This, which is termed "coagulation," 
 
202 ORGANIC CHEMISTRY. 
 
 is brought about by heat in some cases, by different chem- 
 ical agents in others; each proteid requiring particular 
 methods. When quite dry, proteids show little tendency 
 to change. By strong heating they are converted in a 
 mixture of substances, among which pyridin and some 
 of its derivatives are especially noticeable. 
 
 Coagulated Proteids. Under this term are included 
 proteids rendered insoluble in their normal solvents, pure 
 water or saline solutions, as the case may be. In some 
 cases they may be identical with the original body, but 
 in most cases they are probably modified either by hydroly- 
 sis or. oxidation with or without division into two or more 
 new substances. Most of them can be converted into 
 proteoses and finally into peptones by the action of some 
 enzyms, and on this fact depends the digestibility of many 
 articles that are prepared by cooking, by which the pro- 
 teids are coagulated. 
 
 ALBUMINS PROPER. This group, includes ovalbumin 
 (egg albumin), ser albumin (blood albumin) and lactalbumin 
 (milk albumin). Care must be taken not to confuse 
 ''albumin" with "albumen." The latter term refers to 
 the nutritive material surrounding an embryo. It con- 
 tains one or more proteids which may or may not be 
 albumins. White of egg is the "albumen" of the egg. 
 It contains ovalbumin, water and other bodies. The 
 seeds of many plants contain a large amount of material 
 around the embryo. This is called the "albumen" of the 
 seed. In the common cereals this albumen contains 
 several proteids, with much starch and some fatty matter 
 and salts. 
 
 The albumins are soluble in water and in weak saline 
 solutions. In strong saline solution they are coagulated 
 at a temperature of about 60. Alkalies and very small 
 amounts of acids do not precipitate them, but larger 
 
PROTEIDS OR ALBUMINOIDS. 203 
 
 amounts do, as also many neutral salts, among which are 
 ammonium sulphate and mercuric chloride. 
 
 GLOBULINS. Globulins are insoluble in water, but 
 soluble in dilute solutions of sodium chloride. They are 
 precipitated unchanged from these solutions by dilution 
 with pure water. 
 
 Vitellin is obtained from egg-yolk; it resembles some- 
 what the nucleoalbumins. It has not been obtained free 
 from lecithin. 
 
 Crystallin is obtained from the crystalline lens. 
 
 Fibrinogen. This exists in blood plasma. When blood 
 clots, the fibrinogen is converted into fibrin, which forms 
 the clot and encloses the blood corpuscles. This coagu- 
 lation occurs under the influence of another substance, 
 termed "fibrin-ferment," or "thrombin" which also 
 exists in the blood plasma. The nature of thrombin is 
 not known, but it is probably an enzym. 
 
 Myosin is obtained from muscles. According to some 
 authorities, the fluids in living muscles contain a proteid 
 termed myosinogen which is converted after the death of 
 the tissue, when the stiffening (rigor mortis) sets in, into 
 myosin. 
 
 NUCLEOALBUMINS. These are distinguished from most 
 other proteids by containing notable amounts of phospho- 
 rus. The most important is casein, the principal portion 
 of the fresh curd of cow's milk. Some authorities apply 
 the term " caseinogen" to the material as it exists in milk, 
 and the term "casein" to the separated proteid. In fresh 
 milk the casein (caseinogen) exists in association with some 
 calcium phosphate and is probably partly in a jelly-like 
 condition, not in true solution. Most acids, many mineral 
 salts, and several enzyms coagulate milk, but much pro- 
 teid remains in solution, and it is probable that hydrolysis 
 
204 ORGANIC CHEMISTRY. 
 
 occurs, and the original proteids are split into several 
 substances some of which precipitate and others remain 
 dissolved. A solution of mercuric nitrate in excess of 
 nitric acid precipitates all the proteids of cows' milk. 
 
 Cheese is proteid matter obtained from milk either by 
 the action of acids or by rennet, a preparation of enzyms 
 from the stomach of the calf. The acid usually employed 
 is lactic, the result of the natural souring of milk by fer- 
 mentation of milk sugar. Cheese, even when fresh, does 
 not contain the same proteids as milk, and in ripe cheese 
 further changes have occurred through the action of 
 microbes and enzyms, by which amine bodies have been 
 produced. Ammonium compounds are present in well- 
 ripened cheese. Sometimes ptomaines, either amine 
 derivatives or azo-compounds are present, thus making 
 the cheese poisonous. 
 
 ACID-ALBUMINATES AND ALKALI-ALBUMINATES. Many 
 
 proteids combine to a limited extent with acids or with 
 alkalies, producing compounds that have characteristic 
 properties. The exact nature of the combination is not 
 known. By the action of somewhat strong solutions of 
 alkali on natural proteids, chemical changes are produced 
 in the latter, among which are the elimination of nitrogen 
 and sulphur. By dissolving proteids in hydrochloric acid, 
 acid-albuminates may be obtained. Both these products 
 have certain properties in common. * They are nearly 
 insoluble in water and dilute solution of sodium chloride, 
 but are dissolved by water on the addition of a little acid 
 or alkali. The solution is not coagulated by heat, but can 
 be precipitated without heat by neutralising the solvent 
 substance, that is, adding acid to the alkali-albumin and 
 alkali to the acid-albumin. Strong mineral acids pre- 
 cipitate both classes of albuminates. 
 
PROTEIDS OR ALBUMINOIDS. 205 
 
 Syntonin is an acid-albuminate obtained by the action 
 of acids on myosin. 
 
 Albumoses and Peptones. The action of hydrolysing 
 enzyms, such as those in the gastric juice and pancreatic 
 secretions on proteids, results finally in the formation of a 
 substance or mixture of substances, similar to the common 
 proteids in many ways but much more diffusible and much 
 less coagulable. This is called peptone. In the course of 
 its formation from the original proteid, several inter- 
 mediate transformations occur, the products of which are, 
 collectively, called proteases or albumoses. These products 
 differ with the conditions of action and the proteid and 
 enzym, and much remains to be determined in regard to 
 them. At present it is the custom to consider all the 
 proteid matter that is not precipitated by saturated solu- 
 tion of ammonium sulphate, as peptone; that which is so 
 precipitated as either unaltered proteid or some form of 
 proteose. 
 
 HEMOGLOBIN. This is the coloring matter of blood-cor- 
 puscles. It is distinguished from many other proteids by 
 containing iron, which is part of the molecule and not, as 
 with some proteids, merely due to adherent mineral 
 matter. Chlorophyl, the green coloring matter of plants 
 also contains iron, and its functions are analogous to those 
 of hemoglobin. In some animals the iron in hemoglobin is 
 partly or wholly replaced by copper. 
 
 Hemoglobin is very soluble in water, producing a red 
 solution that shows characteristic absorption bands. ' It 
 can be obtained in a crystalline form. Its principal 
 property is the power to take up oxygen and to give this 
 up again under the influence of different substances. The 
 oxygen compound differs slightly in composition according 
 to the pressure of the gas from which the absorption takes 
 
206 ORGANIC CHEMISTRY. 
 
 place. As a rule, hemoglobin absorbs only free oxygen. 
 It has affinity for other bodies, such as nitrous oxide, nitric 
 oxide, hydrogen sulphide, carbon monoxide, carbon dioxide 
 and acetylene. The affinity for carbon monoxide and nitric 
 oxide is stronger than the affinity for most of the other 
 substances. All these derivatives of hemoglobin give 
 characteristic absorption bands. By exposing oxyhemo- 
 globin for some time to the action of free oxygen or to mild 
 oxidising agents, a substance known as methemoglobin is 
 formed. It is believed that in this the oxygen is more 
 strongly combined than is the case with oxy hemoglobin. 
 The associated oxygen of oxyhemoglobin can be driven 
 out by reducing the pressure or by passing through a 
 current of nitrogen or any of the bodies mentioned above 
 as forming compounds with it. 
 
 Hematin is obtained by the action of alkalies or acids 
 on hemoglobin. Its composition approximates the for- 
 mula C 32 H 32 N 4 FeO 4 . Hematin heated to about 80 with 
 glacial acetic acid and a little sodium chloride, yields 
 a chlorine derivative termed hemin. It is regarded as a 
 hydrochloric ester of hematin. It forms characteristic 
 crystals, sometimes termed Teichmann's crystals. The 
 reaction is one of the standard tests for blood. 
 
 Oxyhemoglobin gives with a mixture of guaiacum tinc- 
 ture and hydrogen dioxide a blue solution, the production 
 of which is also a test for blood. 
 
 MUCIN. Under this term several proteids are included. 
 They are found in the secretion of mucous membranes, in 
 connective tissue, tendons and the submaxillary gland. 
 Proteid matter that coagulates with nitric acid, frequently 
 appears in urine. It is also termed mucin, but many 
 authorities regard it as essentially different from true 
 mucin, and properly a nucleoalbumin. True mucin may, 
 
PROTEIDS OR ALBUMINOIDS. 207 
 
 however, be present in urine containing a large amount of 
 mucus. By the action of acids, mucin can be hydrolysed 
 and a reducing carbohydrate formed. 
 
 NUCLEINS. These are a series of bodies containing 
 notable amounts of phosphorus. They are widely dis- 
 tributed in the vegetable and animal kingdom, and have 
 been classified in two groups: Nucleins proper, which 
 yield proteids, phosphoric acid and xanthin bases; and 
 pseudonucleins that yield no xanthin bases. The true 
 nucleins are obtained as insoluble residues in the digestion 
 of nucleoproteids by gastric juice. By the action of 
 alkalies, nucleates are formed, from which nucleic acids may 
 be obtained. All nucleins, by boiling with dilute acids, 
 yield a series of nitrogenous bodies termed the xanthin or 
 nuclein bases. They have close structural relations to 
 some alkaloids, leucomaines and uric acid. It has been 
 suggested that they are all derived from a body having 
 the formula C 5 H 4 N 4 to which the name purin has been 
 applied. Hence the group is often called the " purin 
 bases." (See Purins.) 
 
 KERATIN is the chief proteid constituent of horny struc- 
 tures, hair and nails. Some of its reactions are similar 
 to those of the proteids proper, but it is not digested by 
 gastric or pancreatic secretions. 
 
 ELASTIN occurs in connective tissue, especially the cer- 
 vical ligament. It is insoluble in water, and dissolves 
 only slowly in alkalies and acids. 
 
 COLLAGEN is the material in connective tissue and bone 
 from which gelatin is obtained. GELATIN is prepared by 
 boiling the tissue with water. The process is very slow 
 at ordinary pressure, but in a closed vessel, the tempera- 
 ture can be raised considerably and the gelatin rapidly 
 produced. The change is doubtless a hydrolysis. 
 
208 ORGANIC CHEMISTRY. 
 
 The food material called isinglass is probably a collagen 
 that is easily converted into gelatin. Ordinary gelatin 
 dissolves in hot water, and the solution on cooling sets to a 
 jelly if considerable of the gelatin is present. Solutions 
 of gelatin are promptly precipitated by tannins, common 
 tannins. The tanning of skins is dependent on the reac- 
 tion by which the albuminoids are rendered insoluble and 
 non-putrescent. This was originally carried out by the 
 use of tannins, but several other methods are now in use. 
 Formaldehyde converts gelatin into a mass insoluble in 
 water. 
 
 VEGETABLE PROTEIDS. As a purely vegetable diet will 
 support life satisfactorily for a long period, it is reasonable 
 to suppose that the vegetable proteids are of the same 
 general character as the animal proteids, but the isolation 
 and classification of the former are as yet very incomplete. 
 Recently, careful investigations have been made into the 
 proteids of important cereals. The principal proteids of 
 wheat flour are gliadin and glutenin. The former, which 
 constitutes nearly half the proteid matter of the grain, 
 is soluble in pure water and in dilute alcohol, but almost 
 insoluble in water containing the mineral matters of the 
 wheat -grain. Glutenin is insoluble in water, dilute saline 
 solutions and dilute alcohol. The glutinous property of 
 wheat flour is due to both the proteids, the gliadin giving 
 the adhesiveness and glutenin the solidity. 
 
 LECITHINS. These are complex bodies that occur in the 
 protoplasm of many forms of cells, either alone or in com- 
 bination, or close association, with proteids. A lecithin is 
 an ester derived from glycerophosphoric acid by sub- 
 stitution of two of the hydrogen atoms of the latter by two 
 molecules of radicles of the fatty-acids and the other 
 hydrogen atom by a base " choline." Since the substitut- 
 
PROTEIDS OR ALBUMINOIDS. 
 
 209 
 
 ing radicles may differ, a considerable number of bodies 
 of the same type may be produced. The annexed struc- 
 tural formulas show glycerophosphoric acid and one of the 
 common lecithins. 
 
 H 
 
 4 
 
 H H 
 
 -U-H 
 
 (CH 3 ) 3 N 
 
 OHO 
 
 O= 
 
 H 
 
 A 
 
 ' O-H 
 
 H O=P O H 
 
 H (C 18 H 35 0) 
 
 | \ 
 
 O O O O O 
 
 (C 16 H 81 0) 
 
 H-C C C-H H C C C H 
 
 H H H 
 
 Glycerophosphoric acid 
 
 H H H 
 
 Lecithin 
 
 Experiment 80. Beat a raw egg to a foam, allow the mass to 
 stand until most of the insoluble matter has subsided, dilute with 
 about five times the bulk of water and filter through a plaited 
 filter. This solution does not keep, and hence must be made 
 fresh as needed. Portions of about 10 c.c., unless otherwise 
 directed, should be used for the following experiments. 
 
 Experiment 81. Heat a portion of the solution to boiling. It 
 will not coagulate, add a few drops of acetic acid and boil again, 
 if coagulation does not occur, add more acetic acid and boil, and 
 proceed in this way, adding small quantities of the acid and boiling 
 for a few seconds, until coagulation is obtained. 
 
 Experiment 82. Test separate portions of about 5 c.c. of the 
 liquid with a few drops each of sulphuric acid, hydrochloric acid 
 and nitric acid. 
 14 
 
. 210 ORGANIC CHEMISTRY. 
 
 Experiment 83. Add 5 c.c. of the albumin solution to 20 c.c. 
 of water; divide the solution into two equal portions and test one 
 with a few drops of syrupy phosphoric acid (orthophosphoric acid) 
 and the other with metaphosphoric acid. The former will not 
 coagulate, the latter will produce immediate coagulation. If o.i 
 gram metaphosphoric acid be dissolved in water and the solution 
 kept boiling for half an hour the coagulating property will be lost, 
 as the acid hydrolyses to orthophosphoric. 
 
 Experiment 84. Place about i c.c. of strong nitric acid in a 
 narrow testtube and overlay it with a few c.c. of solution of albu- 
 min. It is best to use a somewhat diluted solution for this. The 
 overlaying can be done by inclining the tube very much and 
 pouring the albumin solution down the side. The coagulated 
 albumin forms a ring at the point of contact between the two 
 liquids. This is known as Heller's test. 
 
 Experiment 85. Portion of the albumin solution may also be 
 tested by the following: saturated solution of picric acid; solution 
 of copper sulphate; solution of mercuric chloride. 
 
 Experiment 86. Prepare Millon's reagent by adding 0.5 c.c. 
 of mercury to 5 c.c. of strong nitric acid. It may be necessary to 
 complete the action by gentle warming, but the liquid should not 
 be boiled. When the mercury is dissolved, the liquid is diluted 
 with twice its volume of water, allowed to stand for some hours 
 and decanted from any deposit that may have formed. It does 
 not keep long. 
 
 Experiment 87. Treat a solution of albumin with some of this 
 reagent. A white precipitate is formed which turns brick-red on 
 boiling. Other proteids give similar effects 
 
 Experiment 88. Treat a solid proteid, such as a little dried 
 white of egg or a piece of wool or silk with strong nitric acid. A 
 yellow color will appear. If ammonium hydroxide be added to 
 the mass, the color will change to orange. This is termed the 
 xanthoproteic reaction. 
 
 Experiment 89. Prepare a stiff jelly from gelatin and water, 
 observing that it can be liquefied by the application of heat. Add 
 a few drops of formaldehyde solution to a small portion of the 
 jelly and allow it to cool. The formaldehyde combines with the 
 gelatin to form an insoluble compound which will char without 
 melting. 
 
ENZYMS. 
 
 Enzyms are nitrogenous bodies analogous in composition 
 and general properties to ordinary proteids, but are distin- 
 guished by power to bring about transformations without 
 being themselves permanently affected. Nothing is known 
 as to their empirical formulas; in fact, they have not been 
 prepared in a perfectly pure condition. They are usually 
 amorphous, colorless or slightly yellow, soluble in water, 
 but not appreciably in other solvents. The solution in 
 water soon putrefies. Some enzyms are affected in- 
 juriously by light, and all of them lose their characteristic 
 functions when heated, resisting, however, this treatment 
 better when dry than in solution. Many substances re- 
 strain the action of enzyms; some of these, such as sali- 
 cylic acid, boric acid and benzoic acid are largely used 
 for controlling or preventing their action. Enzyms are 
 often termed "non-organised ferments," ordinary microbes 
 being designated "organised ferments." 
 
 Each enzym has its peculiar ''optimum" condition, 
 that is, that under which it is most active. Conditions 
 that favor one enzym often restrain or interrupt the 
 action of others. Thus, pepsin (pepsase), the principal 
 enzym of gastric juice, is favored by the presence of a 
 small amount of hydrochloric acid, % but restrained by a 
 larger amount. Trypsin (trypsase), the corresponding 
 enzym of the pancreatic secretion is favored by the 
 presence of a feebly alkaline body. 
 
 The manner of action of enzyms is not known. It has 
 been suggested that they combine temporarily with the 
 substances involved in the reaction and are set free un- 
 changed when new molecules are formed. Thus, the 
 hydrolysis of sucrose by invertase would consist in, first, 
 
212 ORGANIC* CHEMISTRY. 
 
 a combination of sucrose molecules and water, one to one, 
 with a molecule of the enzym; then, an intermingling 
 of the water molecule and sucrose molecule to the ex- 
 clusion of the enzym, which is thus liberated. The 
 molecule formed by the intermingling of the water and 
 carbohydrate is immediately broken into dextrose and 
 levulose. The enzym is free to repeat its action. In 
 theory, therefore, it is inexhaustible; in practice, the 
 accumulation of products and the constantly increasing 
 dilution interfere with and ultimately suspend the action. 
 It has been found experimentally that invertase can 
 hydrolyse 100,000 times its weight of sucrose and still be 
 active. 
 
 Enzyms may be regarded as the connecting link be- 
 tween living and non-living matter. They have some of 
 the characteristics of each class, but they have, as far as 
 known, no power of reproduction. 
 
 The following are some important enzyms, with their 
 source and characteristic actions : 
 
 Diastase. From malt. Converts starch into maltose 
 and dextrin by hydrolysis. Favored by mild alkalinity 
 of solution and restrained by acidity and by salicylic acid. 
 
 Takadiastase (Japanese, taka, strong). From a fungus 
 that grows on bran. Similar to diastase in its action. 
 
 Amylopsin (amylopsase). From pancreatic secretion, 
 similar to diastase. 
 
 Invertase. From yeast, hydrolyses sucrose to a mixture 
 of equal parts of dextrose and levulose (invert-sugar). 
 Favored by very slight acidity. 
 
 Synaptase. From tissues, especially seeds, of plants of 
 the order Rosaceae. It converts amygdalin by hydrolysis 
 into benzaldehyde, dextrose and hydrogen cyanide. 
 
 Myrosin (myrosase). Exists in white and black mus- 
 
ENZYMS. 213 
 
 tard. It hydrolyses sinalbin in the former and sinigrin 
 in the latter, producing the irritating materials upon which 
 the local action of mustard depends. 
 
 Pepsin (pepsase). The principal enzym of gastric 
 juice. It hydrolyses proteids to proteoses and finally to 
 peptones, but the peptonising action is slow and often 
 incomplete. Pepsin is most active in the presence of a 
 small amount of hydrochloric acid. 
 
 Trypsin (trypsase). One of the enzyms of the pan- 
 creatic secretion. It hydrolyses proteids to proteoses and 
 then to peptones, being more rapid than pepsin. It acts 
 best in feebly alkaline solution. By prolonged action pep- 
 tones are hydrolysed to leucin and tyrosin. 
 
 Ptyalin (ptyalase). This is the characteristic enzym 
 of saliva. It hydrolyses starch to maltose and dextrin, 
 and sucrose to dextrose and levulose. 
 
 Steapsin (steapsase). An enzym of the pancreatic se- 
 cretion. It hydrolyses fats to glycerol and free acids. 
 
 A similar enzym exists in the castor bean. 
 
 The juice of the papaw (Carica papaya) contains en- 
 zyms capable of digesting proteids and starch. The juice 
 of the pineapple contains an enzym that digests proteids. 
 
 Catalase. An oxidising enzym obtained from fresh 
 leaf-tobacco, but probably widely distributed. It de- 
 composes hydrogen dioxide. 
 
 Rennin (rennase) is found in gastric juice, especially 
 in that of the fourth stomach of the calf. It is some- 
 times called chymogen. Its characteristic action is the 
 coagulation of milk which is due to a hydrolytic change 
 in the caseinogen, by which this is split into several pro- 
 teids some of which precipitate and others remain in 
 solution. The precipitate and liquid are termed, re- 
 spectively, " curds" and "whey." Rennase in solution is 
 
214 ORGANIC CHEMISTRY. 
 
 rendered inactive by exposure to a temperature of 60 to 
 70 which is somewhat lower than that required for most 
 enzyms. 
 
 Milk contains several enzyms that have digestive and 
 limited oxidising powers, but they have not been satis- 
 factorily isolated. 
 
 The terms proteolytic (proteid-hydrolysing) and amy- 
 lolytic (starch-hydrolysing) are used in connection with 
 enzyms. 
 
 Experiment 90. Make a fresh solution of a small amount of 
 i2 diamidobenzene (paraphenylene diamine, C 6 H 4 (NH 2 ) 2 ) in water, 
 and add portions of it to boiled and unboiled milk in separate 
 testtubes. Add a few drops of hydrogen dioxide to each tube. 
 A deep blue color is produced with the unboiled milk at once, but 
 no appreciable color with the boiled milk until a considerable 
 time has elapsed. The color is due probably to the action of en- 
 zyms in the milk which are injured by the heating. 
 
 If two samples of milk be heated, respectively, to 75 and 82, 
 it will be found that the portion heated to the lower temperature 
 will, when cold, give the above reaction, while that heated to the 
 higher temperature will not give it. At some point between these 
 temperatures is the "death point" of the enzym. The so-called 
 "pasteurising" temperature lies below this death point. It is 
 possible, therefore, to distinguish between pasteurised and boiled 
 (sterilised) milk by this test. 
 
 Experiment 91. Repeat the procedures indicated in Experi- 
 ment 31 with the variation that, before adding the enzyms, about 
 o.i gram of salicylic acid is added to each starch solution. It 
 will be found that the action of the enzym will be suspended, very 
 little if any transformation of the starch taking place. It is pos- 
 sible that this is an inhibitory rather than an enzymocide action. 
 
 Experiment 92. Add i c.c. of strong, pure hydrochloric acid 
 to 150 c.c. of distilled water, and dissolve, without heat, in this 
 solution 0.009 gram of good pepsin. Mix well and divide the liquid 
 into three equal parts. It contains about 0.2 per cent, absolute 
 hydrochloric acid and 0.003 per cent, pepsin, being approximately 
 equivalent to normal gastric juice. 
 
ENZYMS. 215 
 
 To one of the portions of solution add o.i gram of boric acid; 
 to another portion add about 0.3 gram of sodium sulphite. To all 
 three solutions add i gram each of finely-chopped raw meat, and 
 keep them at a temperature of from 38 to 40 for six hours. It 
 *will be found that the sulphite solution has a marked restraining 
 action on the pepsin and the boric acid very little, if any. The 
 actions are probably inhibitory rather than enzymocidal. 
 
INDEX. 
 
 ABIETENE, 53 
 Abietic acid, 153 
 
 anhydride, 153 
 Abrastol, 141 
 Absolute alcohol, 63 
 Acet amide, 171 
 Acetates, 76, 77 
 Acetic acid, 59, 60, 74, 76, 
 80 
 
 , formation 
 
 25 
 , glacial, 76 
 
 78, 
 of, 
 
 aldehyde, 71 
 
 - anhydride, 78 
 
 Aceto-acetic acid, 77 
 Acetone, 73, 74 
 Acetphenetidine, 191 
 Acetylene, 96 
 Acetyl chloride, 80 
 Acid albuminate, 201, 204 
 Acids, 60, 82 
 Aconite, 187 
 Aconitic acid, 89 
 Aconitine, 187 
 Active principles, u 
 Activity, optical, 37 
 Acrolein, 95 
 Acrylic acid, 92 
 Additive, 115, 118 
 
 compounds, 28 
 Adenine, 197, 198 
 Adipic acid, 85 
 Adjacent, 122 
 Aerobic, 26, 193 
 Agar-agar, no 
 Al, 47 
 
 Albumen, 202 
 Albuminates, 201, 204 
 Albuminoids, 200, 202 
 Albumins, 201, 202 
 
 Albumins, coagulated, 201 
 Albumoses, 201, 205 
 Alcohol, 6 1, 63 
 
 , absolute, 63 
 
 , amyl; 59, 60, 66 
 
 - butyl, 60, 61 
 
 , primary, 65 
 
 , secondary, 65 
 
 -, tertiary ,"65 
 
 , caproic, 61 
 , cetyl, 6 1 
 , diatomic, 81 
 
 ethyl, 59, 60, 61, 63 
 
 grain, 63 
 
 hexyl, 6 1 
 -, heptyl, 6 1 
 
 methyl, 59, 60, 61 
 , monatomic, 61 
 , myricyl, 61 
 , nonyl, 61 
 , octyl, 6 1 
 , aenanthic, 61 
 , pentyl, 61, 66 
 , propyl, 60, 6 1 
 -, triakontyl, 61 
 Alcohols, 59, 60, 82 
 , primary, 65 
 -, secondary, 65 
 , sulphur, 70 
 
 , tertiary, 65 
 
 Aldehyde, 59, 71 
 
 , acetic, 71 
 
 , amyl, 60 
 
 , butyl, 60 
 
 , ethyl, 60, 71 
 
 , formation of, 25 
 
 , group, 41 
 
 , methyl, 60, 62, 73 
 
 , propyl, 60 
 Aldehydes, 60, 71 
 
 217 
 
2l8 
 
 INDEX. 
 
 Aldose, ioo 
 Ale, 63 
 Aliphatic, 46 
 
 hydrocarbons, 49 
 Alizarin, 135, 142, 144, 145 
 Alkali albuminate, 201, 204 
 Alkaloids, 176 
 
 , animal, 190 
 
 , cadaveric, 190 
 , types of, 189 
 Alkyls, 51, 58 
 Allo-isomerism, 39 
 Alloxuric bodies, 196 
 Allyl, 94 
 aldehyde, 91 
 
 guaiacol, 132, 152 
 
 isothiocyanate , 165 
 
 sulphide, 94 
 
 thiocarb amide ,114 
 
 thiocyanate, 114 
 Allylene, 97 
 
 Almond shells, 183 
 Alpha-derivatives, 141 
 
 substitutions, 141 
 
 Alphaamidonaphthalene , 1 8 1 
 Alphabet anaphthol, 142 
 Alphanaphthalenesulphonic 
 
 acid, 141 
 
 Alphanaphthol , 141, 142, 183 
 Amber, 153 
 Amid, 41, 48 
 Amides, 166, 171 
 Amidoacetic acid, 171, 173 
 Amidobenzene , 126 
 Amidoethylsulphonic acid, 173 
 Amidobenzenesulphonic acid, 
 
 182 
 
 Amidogen, 41 
 Amidonaphthalene, 142 
 Amidopurin, 198 
 Amidosuccinamic acid, 176 
 Amin, 41, 48 
 Amine, n, 166 
 Amines, 166 
 Ammonia, n 
 Ammoniac, 154 
 Ammonium acetate, 76 
 
 cyanate, 164 
 
 derivatives, 166 
 
 oxalate, 86 
 
 Ammonium valcrate, 79 
 Amygdalin, 112, 161 
 Amyl, 60 
 
 acetate, 58, 69 
 
 alcohol, 59, 60, 66 
 
 aldehyde, 60 
 
 chloride, 58 
 
 ether, 60 
 
 nitrite, 60, 69 
 
 Amyloid, 202 
 Amylolytic, 214 
 Amylopsase, 212 
 Amylopsin, 212 
 Anaerobic, 26, 194 
 Analysis, proximate, n 
 
 , ultimate, n 
 Anchoic acid, 85 
 Ane, 47 
 Anethol, 152 
 Aniline, 126, 183 
 
 colors, 126 
 
 oil, 126 
 
 , preparation of, 138 
 
 red, 146 
 
 , test for, 138, 139 
 Animal oil, Dippel's, 156 
 Anise, oil of, 152 
 Anthracene, 135, 142 
 Anthranilic acid, 137 
 Antifebrin, 191 
 Anthroquinone, 142 
 Antigalline, 114 
 Antipyretics, 191 
 Antipyrin, 191 
 Antitoxins, 194 
 Antiseptics, 26 
 Antizymotic, 25 
 Apomorphine, 186 
 Arabic, gum, no 
 Arachidic acid, 78 
 Argol, 88 
 Arsine, 167 
 Arsonium, 167 
 Asafetida, 154 
 
 resin, 128 
 
 Asaprol, 141 
 Ase, 47 
 
 Asparagin, 175 
 Asymmetric atoms, 37 
 
 carbon, 37 
 
INDEX. 
 
 219 
 
 Atropine, 186 
 Auramin, 145 
 Axial symmetric, 40 
 Azo, 48 
 
 - -colors, 145 
 
 - -compounds, 176, 177 
 Azoimide, 165 
 Azoxy-group, 177 
 
 BEER, 63 
 
 Behenic acid, 78 
 
 Belladonna, 186 
 
 Benzaldehyde, 124, 127 
 
 Benzene, 116, 118 
 
 , production of, 137 
 , structure of, 119 
 
 Benzenes, 115 
 
 Benzidin, 143 
 
 Benzin, 53 
 
 Benzine, 53 
 
 Benzoic acid, 123, 127 
 
 , extraction of , 1 3 9 
 , test for, 139 
 sulphimide, 134 
 
 Benzol, 118 
 
 Benzolene, 53 
 
 Benzoquinone, 133 
 
 Benzoyl glycocoll, 174 
 
 Berberine, 187, 190 
 
 Beta-derivatives, 141 
 
 - -substitutions, 141 
 
 Betaine, 175 
 
 , y, 189, 196 
 
 Betamidonaphthalene , 1 8 1 
 
 Betanaphthalenesulphonic acid, 
 141 
 
 Betanaphthol, 141, 142, 183 
 
 Betanaphtholazobenzene ,178 
 
 Benzyl alcohol, 124, 125, 127 
 
 Baking powders, 88 
 
 Balance, Westphal, 14 
 
 Balsam, Peru, 154 
 
 , tolu, 154 
 
 Bases, xanthin, 196 
 
 Birch, oil of, 68, 131, 152 
 
 Birotation, 106 
 
 Bismarck brown, 145, 179 
 
 Bitter almond oil, 124, 127 
 
 Blood- albumin, 202 
 
 Bloodroot, 187 
 Brandy, 63 
 British gum, no 
 Bromine, action of, 28 
 Bromo, 48 
 Bromethane, 69 
 Bromoform, 56 
 Broom, 186 
 Brucine, 187 
 Brown, Bismarck, 179 
 Boiling point, 17 
 Borneol, 150 
 Burgundy pitch, 153 
 Butane, 45, 50, 52, 54 
 
 , normal, 44 
 
 Butine, 97 
 
 Butter, nature of, 94 
 Butyl, 60 
 
 Butylacetic acid, 175 
 Butyl alcohol, 60, 6 1 
 
 , primary, 65 
 
 , secondary, 65 
 
 , 'tertiary, 66 
 
 aldehyde, 60 
 
 ether, 60 
 
 nitrate, 60 
 
 Butyric acid, 45, 60, 78, 94 
 
 , formation of, 25 
 
 Butyrin, 92 
 
 CACAO, 189 
 Cadaverine, 195 
 Caffeine, 187, 189, 197 
 Calabar bean, 189 
 Calcium oxalate, 83, 86 
 Calculus, mulberry, 86 
 Camphene, 148, 149 
 Camphor, 116, 150 
 
 , artificial, 147 
 , Borneo, 150 
 
 , coal-tar, 140 
 
 , Japan, 150 
 
 , monobromated, 150 
 
 Camphors, 149 
 Cane-sugar, 105 
 Caoutchouc, 149 
 Capric acid, 78 
 Caproic acid, 78, 94 
 alcohol, 6 1 
 
220 
 
 INDEX. 
 
 Caprylic acid, 78 
 Carbamic acid, 172 
 Carbazol, 144 
 Carbides, 97 
 Carbinol, 62 
 Carbohydrates, 73, 99 
 Carbolic acid, 126 
 Carbon chains, 42 
 
 skeletons, 43 
 
 tetrachloride, 55, 56 
 
 Carboxy benzene, 123, 127 
 Carboxyl, 40 
 Carron oil, 80 
 Carvacrol, 130 
 Carvene, 149 
 Casein, 201, 203 
 Casein ogen, 203 
 Castile soap, 79 
 Catalase, 213 
 Citrene, 149 
 Celluloid, 1 08 
 Cellulose, 107 
 Cerptic acid, 78 
 Cerium oxalate', 86 
 Cetyl alcohol, 61 
 Chains, closed, 43 
 
 , open, 43 
 
 Changes, natural, 25 
 Cheese, 204 
 Cheese-poison, 180 
 Chloral, 71, 72 
 
 hydrate, 72 
 
 Chlorine, action of, 28 
 Chloro, 48 
 Chlorbenzenes, 118 
 Chloroform, 55 
 Chlorophyll, 205 
 Choline, 195, 208 
 Chrysophanic acid, 145 
 Cinchona, 186 
 Cinchonidine, 186 
 Cinchonine, 186 
 Cinnamic aldehyde, 152 
 Cinnamon oil, 151, 152 
 Citral, 150, 152 
 Citric acid, 89 
 Citronellal, 150 
 Cis- form, 40 
 Claret, 63 
 Classification, 44 
 
 I Cloves, oil of, 152 
 
 | Coagulated albumins, 201 
 
 , proteids, 201 
 Coagulation, 201 
 Coal-gas, 52 
 
 - -oil, 53 
 
 tar, 117 
 
 camphor, 140 
 
 colors, 126, 144 
 
 kreasote, 126 
 
 Coca, 187 
 Cocaine, 187, 190 
 Codeine, 186 
 Coffee, 187 
 Colchicine, 187 
 Colchicum, 187 
 Collagen, 202, 207 
 Collidin, 158 
 Collodion, 108 
 Colophene, 149 
 Colophony, 153 
 Colors, aniline, 144 
 
 , coal-tar, 144 
 Combining weight, 33 
 Compound ethers, 58, 60 
 
 spirit of ether, 68 
 
 Conine, 158, 186, 189 
 Congo red, 145, 179 
 Consecutive, 122 
 Constants, 12 
 Constituents, active, n 
 , essential, n 
 
 , proximate, n 
 
 , ultimate, n 
 Copaiba, 153 
 Copal, 153 
 Copper acetate, 77 
 
 in organic bodies, 10 
 
 Cosmoline, 53 
 Cotton, gun, 108 
 
 , negative, 108 
 
 , soluble, 1 08 
 Coumarin, 155, 183 
 Cream of tartar, 88 
 Cresols, 127, 132 
 Cresylic acids, 132 
 Crystallin, 201, 203 
 Crystals, Teichman's, 206 
 Cryoscopy, 18 
 Cumene, 124 
 
INDEX. 
 
 221 
 
 Curds, 213 
 Cyanic acids, 163 
 Cyanides, 160 
 
 , complex, 161 
 Cyanogen, 160 
 
 hydroxide, 163 
 Cyanuric acid, 164 
 Cyclic hydrocarbons, 115 
 Cyclo, 115 
 
 Cyclopropane, 115, 116 
 Cymene, 124 
 Cymogene, 52 
 Cystin, 175 
 Cytoglobin, 202 
 
 DAMMAR, 153 
 
 Daturine, 188 
 
 Decane, 54 
 
 Decay, 25, 26 
 
 Density, vapor, 17 
 
 Dehydrolysis, 27 
 
 Dehydrolysing agents, 27 
 
 Derivatives, 24 
 
 Desmotropic, 36 
 
 Destructive distillation, 24 
 
 Dextrin, 109 
 
 Dextrorotatory, 37 
 
 Dextrose, 101, 184 
 
 Di, 47 
 
 Diamidobenzene, 214 
 
 Diamidodiphenyl, 143 
 
 Diamines, 167 
 
 Diammoniums, 167 
 
 Diatomic alcohols, Si 
 
 Diastase, 212 
 
 Diazo, 48 
 
 - -compounds, 176, 180 
 reaction, Ehrlich's, 183 
 
 Diazobenzene butyrate, 180 
 
 nitrate, 177 
 
 sulphate, 177, 180 
 Diazonium compounds, 180 
 
 sulphate, 177 
 Diazotising, 178 
 Dicarboxybenzenes, 133 
 Dicarboxyl, 82, 83 
 Dichloracetic acid, 80 
 Dichlormethane, 55 
 Digallic acid, 113 
 
 Dihydroxy ethane, 82 
 Dinitroalphanaphthols ,141 
 Diose, 100 
 
 Disaccharids, 99, 105 
 Distillation, destructive, 24 
 
 , fractional, 29 
 
 Diethenediamine, 195 
 Diethylamine, 168 
 Di-isopropyl methane, 54 
 Dimethyl ketone, 74 
 Dimethylanilines, 126 
 Dimethylbenzenes, 124 
 Dimethylxanthin, 198 
 Dimyricyl, 54 
 Dipentene, 149 
 Diphenyl, 144 
 
 ketone, 142 
 
 Dippe!' s animal oil, 156 
 Diterpenes, 147 
 Docosane, 54 
 Dodecane, 54 
 Dotriacontane, 54 
 Drying oils, 91, 96 
 Dulcite, 105 
 Dulcitol, 105 
 Dutch liquid, Si 
 Dynamite, 91 
 
 EGG-ALBUMIN, 202 
 
 white of, 202 
 
 yolk, 203 
 
 Eicosane, 54 
 Elastin, 202, 207 
 Electricity, action of, 30 
 Eleoptenes, 149 
 Emetine, 189 
 Empirical formula, 35 
 Enanthylic acid, 78 
 Ene, 47 
 
 Enzyms, 24, 46, 211 
 Eosins, 136, 145 
 Erythrosin, 136 
 Eserine, 189 
 Essential oils, 147, 151 
 
 principles, n 
 
 Esters, 58, 60, 68, 91 
 Ethanal, 71 
 Ethane, 43, 50, 52 
 Ethene, 81 
 
INDEX. 
 
 Ethene, dichloride, 81 
 - glycol, 81, 82 
 
 oxide, 82, 154 
 lactic acid, 84 
 
 Ethenediamine, 169 
 Ether, 67 
 
 , amyl, 60 
 
 , butyl, 60 
 
 , compound, 68 
 - , compound spirit of, 68 
 
 , ethyl, 59, 60, 67 
 
 , methylethyl, 59, 68 
 
 , propyl, 60 
 
 , sulphuric, 67 
 Ethers, 66, 82 
 
 , mixed, 59 
 Ethereal oil, 68 
 Ethine, 96 
 Ethyl, 60 
 
 acetate, 69 
 
 alcohol, 59, 60, 61, 63 
 
 aldehyde, 59, 60, 71 
 bromide, 69 
 
 butyrate, 69, 79 
 
 ether, 58-60 
 nitrite, 60, 69, 70 
 
 oxide, 67 
 
 sulphide, 70 
 . Ethylene, Si 
 
 Eugenol, 130, 132, 152 
 Exalgin, 192 
 Extract, Goulard's, 77 
 
 FATS, 91 
 
 Fatty-acids, 74, 93 
 Fibrin, 201, 203 
 
 ferment, 203 
 
 Fibrinogen, 201, 203 
 
 Firedamp, 52 
 
 Fixed oils, 91 
 
 Fractional distillation, 24, 29 
 
 Freezing point of solution, 18, 
 
 3 2 
 
 Fructose, 102 
 Fruit sugar, 102 
 Fermentation, 25, 193 
 Ferments non-organised, 211 
 
 , organised, 211 
 
 Ferricyanides, 162 
 
 Ferrocyanides, 162 
 
 Fluorescein, 135, 145 
 
 Formaldehyde, 60, 62, 73 
 
 Formalin, 73 
 
 Formic acid, 60, 75, 76, 78 
 
 Formula, 30 
 
 empirical, 35 
 
 general, 36, 42 
 
 graphic, 35 
 molecular, 35 
 
 rational, 35 
 
 stereochemic, 36 
 
 structural, 35 
 Fuchsin, 145, 146 
 Fulminates, 164 
 Fulminic acid, 163 
 Fulminuric acid, 164 
 Fumaric acid, 40 
 Furfural, 155, 184 
 Furfurane, 155 
 Furfurosazone, 184 
 Fusel oil, 6 1, 64, 66 
 
 GALACTOSE, 106 
 
 Galbanum resin, 128 
 
 Gallic acid, 114, 115 
 
 Gallotannic acid, 113 
 
 Gamboge, 154 
 
 Garlic, oil of, 95 
 
 Gas, olefiant, 81 
 
 Gasolene, 52 
 
 Gaultheria oil, 152 
 
 Gelatin, 207 
 
 Gelsemine, 187 
 
 General formula, 36, 42 
 
 Geraniol, 150, 152 
 
 Glacial acetic acid, 76 
 
 Gliadin, 208 
 
 Globulins, 201, 203 
 
 Glucose, 10 1, 184 
 
 Glucosides, 112 
 
 Glutenin, 208 
 
 Glycerin, 90 
 
 Glycerol, 80, 90 
 
 formic ester, 75 
 
 Glycerophosphates, 93 
 
 Glycerophosphoric acid, 93, 209 
 ; Glycerose, 101 
 i Glycin, 173 
 
INDEX. 
 
 22 3 
 
 Glycocoll, 173 
 
 , benzoyl, 174 
 , trimethyl, 175 
 
 Glycogen, 108 
 
 Glyceryl, 90 
 
 Glycolic acid, 82, 83 
 
 Glyclos, 8 1 
 
 Glycoproteids, 202 
 
 Glycuronic acid, 104 
 
 Gold orange, 178 
 
 Golden seal, 189 
 
 Goulard's extract, 77 
 
 Grain alcohol, 63 
 
 Grape sugar, 101 
 
 Graphic formula, 35 
 
 Gravity, specific, 12 
 
 Green soap, 80 
 
 Guaiacol, 130, 153 
 , allyl, 132 
 
 carbonate, 130 
 Guaiac resin, 153 
 Guanine, 197 
 Guarana, 189 
 
 Gum arabic, no 
 
 , British, no 
 
 resins, 153, 154 
 - tragacanth, 110 
 
 Gun-cotton, 107 
 Gutta-percha, 149 
 
 HEAT, action of, 24 
 Heavy oil of wine, 68 
 Helianthin, 178 
 Hemin, 206 
 Hemiterpenes, 147 
 Hemoglobins, 202, 205 
 Henbane, 186 
 Heneicosane, 54 
 Hentriacontane, 54 
 Heptacosane, 54 
 Heptadecarie, 54 
 Heptane, 50, 52, 54 
 Heptyl alcohol, 61 
 Heroine, 188 
 Hesperidine, 159 
 Heterocyclic, 115 
 
 compounds, 154 
 
 Hexane, 50, 52, 54 
 Hexadecane, 54 
 
 Hexadecyl alcohol, 61 
 Hexane, 50, 52, 54 
 Hexine, 97 
 
 Hexmethenetetramine ,170 
 Hexose, 100, 101 
 
 alcohols, 104 
 Hexyl alcohol, 69 
 Hilum, 109 
 Hippuric acid, 174 
 Hock, 63 
 
 Hoffmann's anodyne, 68 
 Homatropine, 188 
 Homocyclic, 115 
 Homologous, 41 
 Hyalogens, 202 
 Hydrastine, 187 
 Hydrastinine, 187 
 Hydrazins, 177, 183 
 Hydrazo, 177 
 Hydrazoates, 166 
 Hydrazobenzene, 177 
 Hydrazo-group, 177 
 Hydrazoic acid, 165 
 Hydrocarbon radicles, 49 
 Hydrocarbons, aliphatic, 49 
 
 , cyclic, 115 
 
 Hydrocyanic acid, 161 
 Hydrogen cyanide, 161 
 Hydrolysis, 26 
 Hydrometers, 15 
 Hydroxides, 60, 82 
 Hydroxybenzene, 123, 126 
 Hydroxyl, 40 
 Hydroxymethane , 62 
 Hydroxymethylbenzene ,125 
 Hydroxynaphthalenes, 141 
 Hydroxy toluene, 125, 127, 132 
 Hyenic acid, 78 
 Hypoxanthin, 197, 198 
 Hyoscine, 186 
 Hyoscyamine, 186 
 
 IDE, 167 
 
 Imid, 41, 48 
 
 Imido-diphenyl, 144 
 
 Imidogen, 41 
 
 Imin, 41, 48 
 
 Immiscible solvent, 138, 185 
 
 In, 47 
 
224 
 
 INDEX. 
 
 Indican, 114, 136 
 
 Lactic acid, 82 
 
 Indigo, 136 
 
 
 , siercocnemic 
 
 
 
 uiue, i -i 4 
 Indigotin, 114, 136, 137 
 
 iormuid,s 01, 37 
 Lactic, anhydride, 84 
 
 Indin, 136 
 
 Lactide, 84 
 
 Indol, 136 
 
 Lactose, 106, 184 
 
 Indoxylcarboxylic acid, 137 
 
 Lager beer, 63 
 
 Ine, 46, 167 
 
 Laurie acid, 78 
 
 Inulin, 109 
 
 Lavender, oil of, 152 
 
 Invertase, 105, 212 
 
 Lead acetate, 77 
 
 Inversion, 105 
 
 oxyacetate, 77 
 
 Invert sugar, 105 
 Iodine, action of, 28 
 
 
 JJJLcLoLtpl, OO, 94 
 
 , subacetate, 77 
 
 
 
 , numoer, 95 
 
 , sugar 01, 77 
 
 lodo, 48 
 
 water, 77 
 
 lodoform, 56 
 
 Lecithins, 196, 208 
 
 Ipecac, 187 
 
 Lemon, salt of, 86 
 
 Isinglass, 208 
 
 
 on, i49> 5 > 5 
 
 Iso, 39 
 
 Leucic acid, 83 
 
 Isobutane, 44 
 
 Leucins, 175 
 
 Isocyanates, 165 
 
 Leucomaines, 176, 190, 193, 194 
 
 Isocyanic acid, 163 
 
 Levorotatory, 37 
 
 Isocyanides, 160 
 
 Levulose, 102, 109, 184 
 
 Isocyclic, 115 
 
 Light, action of, 30 
 
 Isomeric, 39 
 
 Ligroin, 52 
 
 Isomerism, 43 
 
 Limonene, 149, 152 
 
 Isonitrile, 139 
 
 Linalool, 150, 152 
 
 I so vanillin, 124 
 
 Liquid smoke, 76 
 
 
 Lutidine, 158 
 
 
 Lyddite, 131 
 
 JABORANDI, 187 
 
 Lysol, 132 
 
 KERATIN, 202, 207 
 
 MADEIRA wine, 63 
 
 Keroselain, 53 
 
 Magenta, 145, 146, 147 
 
 Kerosene, 53 
 
 Malachite green, 145 
 
 Ketones, 73, 74 
 
 Maleic acid, 40 
 
 Ketonic colors, 145 
 
 Malic acid, 87 
 
 - group, 41 
 
 Malonic acid, 82, 85 
 
 Ketose, 100 
 
 Malt, 212 
 
 Kjeldahl method, n 
 
 Maltose, io6~, 184 
 
 Kola, 187 
 
 Malt sugar, 106 
 
 Koumyss, 83 
 
 Manna, 105 
 
 Kreasote, 130 
 
 Margarin, 92 
 
 coal tar 1^6 
 
 Margaric acid, 78 
 
 , test for, 139 
 
 Marsh gas, 45, 51 
 
 
 Martius' yellow, 141 
 
 
 Mandarin orange, 178 
 
 LAC, 153 
 
 Mannitol, 104 
 
 Lactalbumin, 201, 202 
 
 Mannite, 104 
 
INDEX. 
 
 225 
 
 Mead, 63 
 Mellissic acid, 78 
 Mellitic acid, 123 
 Melting point, 15 
 Menthol, 150 
 Mercaptans, 70 
 Mercury fulminate, 164 
 Mesotartaric acid, 38 
 Mesotomy, 84 
 Meta, 121 
 
 Metadihydroxybenzene ,127 
 Metamerism, 38, 39 
 Methane, 43, 45, 50, 51 
 Methemoglobin , 206 
 Methene, 81 
 
 chloride, 55 
 
 glycol, 82 
 
 Methenyl, 91 
 
 chloride, 55 
 
 series, 90 
 
 Methine, 96 
 
 Methyl, 60 
 
 acetanilid, 192 
 
 acetate, 60, 68 
 
 alcohol, 59, 60, 61 
 aldehyde, 60, 62 
 
 amidoacetate, 174 
 amine, 169 
 
 anilines, 126, 146 
 
 chloride, 55, 58 
 
 glycocoll, 174 
 
 orange, 145, 178 
 
 phenols, 132 
 
 propane, 44 
 
 pyndins, 158 
 - violet, 146 
 
 salicylate, 68, 132, 152 
 
 Methylated spirit, 62 
 Methylbenzene, 124 
 Methylene series, 90 
 
 blue, 146 
 
 ether, 58-60 
 
 Methylethyl ether, 68 
 Millon's reagent, 210 
 Milk, 89 
 
 albumin, 202 
 
 , pasteurised, 214 
 , sterilised, 214 
 sugar, 83, 1 06 
 Mindererus, spirit of, 76 
 
 Mixed ethers, 59 
 Molecular formula, 35 
 Monatomic alcohols, 61 
 
 alcohol radicle series, 58 
 
 Mono, 47 
 
 Monobromated camphor, 150 
 
 Monochloracetic acid, 80 
 
 Monochlormethane, 55 
 
 Monosaccharids, 99, 100 
 
 Monose, 100 
 
 Morphine, 186, 188, 190 
 
 Morphium, 186 
 
 Mucic acid, 104 
 
 Mucins, 202, 206 
 
 Mulberry calculus, 86 
 
 Murexid test, 193 
 
 Muscarine, 196 
 
 Mustard, oil of, 95, 114, 151, 
 
 152, 165 
 
 Myosin, 201, 203 
 Myrbane, oil of, 126 
 Myricyl alcohol, 61 
 Myristic acid, 78 
 Myronate, potassium, 114 
 Myrosase, 212 
 Myrosin, 114, 212 
 Myrrh, 154 
 
 NAPHTHALENE, 140 
 
 ring, 140 
 
 Naphthol green, 145 
 
 yellow, 141, 145 
 
 yellow S, 141, 145 
 Naphthols, 141, 142 
 Narcotine, 186 
 Natural bases, 185 
 
 changes, 25 
 
 gas, 52 
 
 Negative cotton, 108 
 
 Neurine, 195, 196 
 
 Nicotine, 186 
 
 Nitre, sweet spirit of, 69 
 
 Nitric acid, action of, 27 
 
 Nitro, 48 
 
 Nitrobenzene, 123, 126, 127 
 
 , preparation of, 138 
 
 Nitro-colors, 145 
 
 compounds, 28 
 
226 
 
 INDEX. 
 
 Nitrogenated oils, 151 
 Nitroglycerin, 91 
 Nitrophenols, 130, 139 
 Nitroprussic acid, 162 
 Nitroso, 48 
 
 colors, 145 
 
 Nomenclature, 44 
 Nonadecane, 54 
 Nonane, 54 
 Non-drying oils, 92 
 
 organised ferments, 211 
 
 Nonyl alcohol, 61 
 Nucleates, 207 
 Nucleoalbumin, 201, 203 
 Nucleohiston , 202 
 Nucleoproteids, 202 
 Nucleus, purin, 196 
 Nux vomica, 187 
 
 OCTADECANE 54 
 
 Octane, 54 
 Octyl alcohol, 61 
 CEnanthic alcohol, 61 
 Oil, aniline, 126 
 
 , anise, 152 
 
 , birch, 68, 131 
 
 , bitter-almond, 124, 127 
 
 , car r on, 80 
 
 , cinnamon, 151, 152 
 
 , cloves, 152 
 
 , fusel, 61, 64, 66 
 
 , garlic, 95 
 
 , lavender, 152 
 
 , lemon, 149, 151, 152 
 
 , mustard, 95, 114, 151 
 
 , myrbane, 126 
 
 , orange peel, 149, 152 
 , orris, 152 
 
 , pennyroyal, 152 
 
 , peppermint, 152 
 
 , pimenta, 152 
 
 1 rose, 152 
 
 , sassafras, 152 
 
 , thyme, 130 
 
 , turpentine, 147, 151 
 
 , violets, 152 
 
 , wine, heavy, 68 
 
 , wintergreen 68, 151 
 
 Oils, drying, 91 
 
 Oils, essential, 151 
 
 ethereal, 68 
 
 fixed, 91 
 
 nitrogenated, 151 
 
 non-drying, 92 
 
 oxygenated, 151 
 
 sulphurated, 151 
 
 volatile, 151 
 
 Ol, 40, 47 
 Olefiant gas, 81 
 Olefins, 51, 8 1 
 Oleic acid, 92, 95 
 Olein, 92, 95 
 Oleoresins, 153 
 One, 47 
 Onium, 167 
 Open chain, 46 
 
 hydrocarbons, 49 
 
 Opium, 1 86 
 Optical activity, 37 
 Orange III, 178 
 
 flower water, 151 
 
 , gold, 178 
 
 , mandarin, 178 
 
 , methyl, 178 
 
 oil, 149 
 
 peel oil, 149, 152 
 Orris oil, 152 
 
 Ortho, 121 
 
 Osazones, 100, 103, 184 
 
 Ose, 47 
 
 Ovalbumin, 201, 202 
 
 Oxalic acid, 82, 83, 85 
 
 Oxides, 60, 82 
 
 Oxy, 1 20 
 
 Oxybenzoic acid, 124, 131 
 
 Oxybutyric acid, 82, 83 
 
 Oxygen, action of, 25 
 
 Oxygenated oils, 151 
 
 Oxyhemoglobin , 206 
 
 Oxypurin, 198 
 
 Oxy valeric acid, 83 
 
 PALMITIC acid, 78 
 Palmitin, 92 
 Para, 39, 121 
 Paraffin, 53 
 
 series, 51 
 
 Paraform aldehyde, 73 
 
INDEX. 
 
 227 
 
 Paralactic acid, 84 
 Paraldehyde, 71 
 Paraxanthin, 197, 198 
 Paper, 107 
 
 , parchment, 107 
 Parchment paper, 107 
 Pasteurised milk, 214 
 Pawpaw*, 213 
 Pelargonic acid, 78 
 Pellet ierine, 187 
 Pennyroyal, oil of, 152 
 Pentadecane, 54 
 Pentane, 50, 52, 54 
 Pentatriacontane, 54 
 Pen tine, 97 
 Pentose, 73, 100, 101 
 Pentyl alcohol, 61, 66 
 Pentylic acid, 79 
 Peppermint, oil of, 152 
 Pepsase, 211, 213 
 Pepsin, 211, 213 
 Peptones, 201, 205 
 Percentage composition, 30 
 Peru balsam, 154 
 Petrolatum, 53 
 Phellandrene, 149 
 Phenacetin, 191, 192 
 Phenates, 127 
 Phenazone, 191 
 Phenazine, 134 
 Phene, 118 
 Phenic acid, 126 
 Phenol, 123, 126, 183 
 Phenolamidopropionic acid, 175 
 Phenol disulphonic acid, 139 
 Phenolphthalein , 315, 145 
 Phenolsulphonic acid, 129 
 
 , preparation of, 
 
 J 39 
 
 Phenol, test for, 139 
 Phenyl, 120 
 
 acid sulphate, 129 
 Phenylamine, 126 
 Phenylates,. 127 
 Phenyl carbinol, 127 
 
 ether, 135 
 
 Phenylcarbamine, 139 
 Phenyl dimethylpyrazolon ,191 
 Phenylene, 120 
 Phenylhydrazin, 177, 183 
 
 Phenylhydrazin hydrochloride, 
 
 183, 184 
 
 Phenylic acid, 126 
 Phenylmethane derivatives, 145 
 Phenylsulphuric acid, 129 
 Phloridzin, 128 
 Phloroglucol, 128, 181 
 Phosphines, 167 
 Phosphonium, 167 
 Phthal amide, 137 
 Phthaleins, 135 
 Phthalic acids, 133, 134 
 Phthalins, 135 
 Physostigmine, 187 
 Picoline, 158 
 
 Picrates, preparation of, 139 
 Picric acid, 124, 130, 145 
 , preparation of, 
 
 I 39 
 
 Pilocarpine, 189 
 Pimelic acid, 85 
 Pimenta, oil of, 152 
 Pinene, 147, 148, 152 
 Piperazin, 170, 195 
 Piperidin, 158 
 Piperin, 158 
 Piperonal, 132 
 Pitch, Burgundy, 153 
 Plane, symmetric, 40 
 Plaster, lead, 80 
 Poison, cheese-, 180 
 Polarimeters, 20 
 Polarimetry, 19 
 Polymerism, 38, 39 
 Polynucleated compounds, 116 
 Polysaccharids, 99, 107 
 Polyterpenes, 147 
 Pomegranate, 189 
 Porter, 63 
 Port wine, 63 
 Potassium, action of, 28 
 cyanate, 164 
 
 cyanide, 160 
 
 isothiocyanate, 165 
 
 thiocyanate, 165 
 Primary alcohols, 65 
 
 amines, 168 
 
 Principles, active, n 
 
 , essential, n 
 
 , proximate, n 
 
228 
 
 INDEX. 
 
 Principles, ultimate, n 
 
 Proof spirit, 63 
 
 Propane, 43, 50, 52, 115 
 
 Propargyl alcohol, 98 
 
 Propenyl, 90, 94 
 
 Propine hydroxide, 98 
 
 Propionic acid, 60, 78 
 
 Propyl, 60 
 
 alcohol, 60, 6 1 
 
 aldehyde, 60 
 
 ether, 60 
 
 Propylene, 90 
 
 Proteids, 200 
 
 , coagulated, 201 
 , vegetable, 208 
 
 Proteolytic, 214 
 
 Proteoses, 205 
 
 Protocatechuic aldehyde, 134 
 
 acid, 153, 154 
 
 Prussian blue, 162 
 
 Prussiate of potash, red, 162 
 , yellow, 12 
 
 Prussic acid, 161 
 
 Proximate analysis, n 
 composition, 10 
 
 principles, n 
 
 Pseudonucleins, 207 
 
 Ptyalase, 213 
 
 Ptyalin, 213 
 
 Ptomaines, 176, 190, 193, 194 
 
 Pulegone, 152 
 
 Purin, 196, 207 
 
 nucleus, 196 
 
 Purins, 176 
 
 , endogenous, 199 
 
 , exogenous, 199 
 
 Putrefaction, 25, 26, 193 
 
 Putrescine, 195 
 
 Pyknometer, 12 
 
 Pyridin, 156 
 
 hydride, 158 
 
 Pyridins, methyl, 158 
 
 Pyro, 48 
 
 Pyrogallic acid, 128 
 
 Pyrogallol, 128 
 
 Pyroligneous acid, 76 
 
 Pyrotartaric acid, 25, 85 
 
 Pyroxylin, 107 
 
 Pyrrin, 156 
 
 Pyrrol, 155 
 
 }UINIDINE 186 
 Juinine, 186, 189 
 Jjuinolin, 156 
 Juinone, 133 
 juinones, 133 
 
 RACEMIC acid, 38, 88 
 Racemism, 38 
 Radicles, 49, 60, 82 
 
 , organic, 40 
 
 Raffinose, 106 
 Rancidity, 92 
 Rational formula, 35 
 Red oil, 95 
 
 , Congo, 179 
 
 Rennase, 213 
 Rennin, 213 
 Resin, guaiac, 153 
 
 soaps, 153 
 
 Resins, 152 
 
 , gum, 154 
 
 , oleo, 154 
 
 , true, 153 
 
 Resorcin, 124, 127, 154 
 Resorcinol, 124, 127, 154 
 
 , phthalein, 135 
 Rhigolene, 52 
 Rhodamin, 136, 145 
 Rhus glabra, 87 
 Ring symbols, 120 
 Rocellic acid, 85 
 Rochelle salt, 89 
 Root beer, 63 
 Rosaniline, 146 
 Rose oil, 152 
 
 water, 151 
 
 Rosin, 153 
 Rotatory power, 22 
 
 SABADILLA, 187 
 Saccharic acid, 104 
 Saccharin, 134 
 
 , test for, 139 
 
 Salicylic acid, 124, 131 
 
 , test for, 138 
 
 Salicin ,112 
 Saligenin, 112 
 Salt of lemon, 86 
 
INDEX. 
 
 229 
 
 Salt of sorrel, 86 
 Salt, Rochelle, 89 
 Sanguinarine, 187 
 Sapo mollis, 80, 93 
 Saponification , 91, 93 
 Sarkolactic acid, 84 
 Sarkosin, 174 
 Sassafras oil, 152 
 Sebacic acid, 85 
 Secondary alcohols, 65 
 
 amines, 168 
 
 Seralbumin, 201; 202 
 
 Sesquiterpenes, 147 
 
 Shellac, 153 
 
 Side-chain substitution, 125 
 
 Sinalblin, 114 
 
 Sinigrin, 114 
 
 Skatol, 136 
 
 Smoke, liquid, 76 
 
 Smokeless powder, 108 
 
 Soap, 79, 91, 92, 93 
 
 green, 80 
 
 resin, 153 
 
 Sodium, action of, 28 
 
 ethoxide, 64 
 ethylate, 64 
 
 phenate, 131 
 Soluble cotton, 108 
 
 tartar, 89 
 
 Solidifying point, 15 
 Solution, freezing of, 18 
 Sorbite, 105 
 Sorbitol, 105 
 
 Sorrel, salt of, 86 
 Soudan I, 178 
 Sparteine, 186 
 Specific gravity, 12 
 
 , bottle, 12 
 
 , rotatory power, 22 
 Spirit of ether, 68 
 
 , methylated, 62 
 
 of mindererus, 76 
 
 of nitre, sweet, 69 
 
 of wine, 63 
 
 proof, 63 
 
 , wood, 6 1 
 
 Spirits, 63 
 Sprengel tube, 12 
 Spruce-beer, 63 
 St. Ignatia bean, 189 
 
 Starch, 108, 184 
 
 solution , 1 1 o 
 
 Steapsase, 213 
 Steapsin, 213 
 Stearic acid, 78, 79 
 Stearin, 79, 92 
 Stearoptenes, 149 
 Stereochemic formula, 36 
 Sterilised milk, 214 
 Stibine, 167 
 Stibonium, 167 
 Structural formula, 35 
 Strychnine, 187 
 Storax, 154 
 Suberic acid, 85 
 Substitutive, 118 
 
 compounds, 28 
 
 Succinic acid, 82, 85, 86 
 Sucrose, 105, 184 
 Sugar, cane, 105 
 
 milk, 83, 1 06. 
 
 of lead, 77 
 
 Sulphanilic acid, 124, 181 
 Sulphethylic acid, 58 
 Sulpho, 48 
 Sulphocyanates, 164 
 Sulphonate, 48 
 Sulphonation, 178 
 Sulphonic, 48 
 Sulphovinic acid, 58 
 Sulphur alcohols, 70 
 Sulphurated oils, 151 
 Sulphuric ether, 67 
 Sulphuric acid, action of, 28 
 Sylvestrine, 149 
 Symmetric, 122 
 Synaptase, 112, 161, 212 
 Synthesis, 24 
 Synthetic compounds, 24 
 
 TAKADIASTASE, 212 
 
 Tannins, 113 
 
 Tar, beechwood, 130 
 
 , coal, 117 
 
 Tartar, 88 
 
 , cream of, 88 
 
 emetic, 89 
 
 , soluble, 89 
 
 Tartaric acid, 38,1:87 
 
230 
 
 INDEX. 
 
 Taurin, 173 
 Taurocholic acid, 173 
 Tautomeric, 36, 128, 133 
 Tea, 187 
 
 Teichmann's crystals, 206 
 Terebene, 149 
 Terpenes, 116, 147, 151 
 Terpinene, 148, 149 
 Terpin hydrate, 147 
 Terpinolene, 149 
 Tertiary alcohols, 65 
 
 amines, 168 
 
 Tetrabromfluorescein , 136 
 Tetracosane,54 
 Tetrachlormethane, 55 
 Tetradecane, 54 
 Tetraiodofluorescein , 136 
 Tetramethenediamine ,195 
 Tetr amethylatnrnoniuni , 169 
 Tetramethylbenzenes , 124 
 Tetramethyl methane , 5 4 
 Tetramines, 167 
 Tetrammoniums, 167 
 Tetrazo-compounds, 179 
 Tetrylic acid, 78 
 Tewfikose, 106 
 Thalleioquin reaction, 192 
 Theine, 189 
 
 Theobromine, 187, 189, 197 
 Theophyllin, 187 
 Thiacetic acid, 71 
 Thio, 48, 70 
 Thiocyanates, 163, 164 
 Thiophene, 155, 156 
 Thiosinamin, 114 
 Thrombin, 203 
 Thyme oil, 130 
 Thymol, 124, 129 
 Tobacco, 1 86 
 Tolu balsam, 154 
 Toluene, 124 
 Toluidines, 126, 146 
 Toxins, 194 
 Tragacanth, no 
 Trans- form, 40 
 Transformations, 24 
 Tri, 47 
 
 Triakontyl alcohol, 61 
 Triamines, 167 
 Triammoniums, 167 
 
 Tribromphenol, 139 
 Trichloracetic acid, 80 
 Trichloraldehyde, 72 
 Trichlorethene glycol, 73 
 Trichlormethane, 55 
 Tricosane, 54 
 Tridecane, 54 
 Triethylamine, 168 
 Trihydroxybenzene, 128 
 Triketohexamethene , 128 
 Trimethene, 115 
 Trimethylamine , 169 
 Trimethylbenzene, 124 
 Trimethylethyl methane, 54 
 Trimethyl methane, 54 
 Trinitrophenol , 124, 130 
 Triose, 100, 101 
 Trioxypurin, 198 
 Trisaccharids, 99, 106 
 Tritenyl, 90 
 
 Tropeolin, Porrier's, 178 
 Trypsase, 211, 213 
 Trypsin, 211, 213 
 Turpentine, 153 
 
 oil, 147, 151 
 Ty rosin, 175 
 Tyrotoxicon, 180 
 
 ULTIMATE analysis, n 
 
 composition, n 
 constituents, 10 
 
 Undecane, 54 
 Unsaturated, 95 
 
 fatty bodies, 95 
 Unsymmetric, 122 
 Urea, 164, 171 
 
 , synthesis of, 172 
 
 Uric acid, 197, 198 
 , test for, 193 
 
 VANILLIN, 124, 130, 181, 183 
 
 , synthetic, 132 
 
 Valerianic acid, 60, 78, 79 
 
 Valeric acid, 60, 78, 79 
 
 Vaseline, 53 
 
 Vinegar, 176 
 
 Vapor density, 17,31 
 
 Vegetable proteids, 208 
 
 Veratrine, 187 
 
INDEX. 
 
 2 3 T 
 
 Verdigris, 77 
 Vinic acids, 58 
 Violets, oil of, 152 
 Vitellin, 201, 203 
 Volatile oils, 151 
 
 WATER hemlock, 188 
 
 , lead, 77 
 
 Wax oil, 53 
 
 Weight, combining, 33 
 
 Westphal balance, 14 
 
 Whey, 213 
 
 Whiskey, 63 
 
 Wine, heavy oil of, 68 
 
 Wine, Madeira, 63 
 
 , Port, 63 
 
 , spirit of, 63 
 Wintergreen oil, 68, 131 
 Wood spirit, 61 
 
 XANTHIN, 197, 198 
 
 bases, 196, 207 
 
 Xylene, 124 
 Xylidines, 126 
 
 YELLOW jasmine, 189 
 , naphthol, 41 
 
I *>