Alkyne substituent effects in the methylenecyclopropane rearrangement as well as solvolysis studies of the structurally similar trifluoroacetates were determined. The results of these kinetic studies fell into a range that was expected. In the methylenecyclopropane rearrangement all studied systems are moderate radical stabilizers, rearranging more quickly than the parent system. Solvolytic studies showed that the sigma + values for the para-substituted trifluoroacetates are relatively similar, with the para-acetylene group the only system that showed rate retardation in reference to the parent para-hydrogen system. The studies also showed the gamma + value of the 1,2,3-triazole system is better at stabilizing a developing carbocation by a factor of 39 than a phenyl ring. This is due to further delocalization of the carbocation.