The Reactivity of 2-(4-Phenylsubstituted)-α,β-Unsaturated Carboxylic Acids with Diazodiphenylmethane

Abstract

In connection with a study of the transmission of polar effects through ring double bonds, double bonds in open chain systems and delocalized double bonds, the reactivity of 2-(4-phenylsubstituted)-α,β-unsaturated carboxylic acids with diazodiphenylmethane in ethanol was investigated. The rate data for 2-(4-phenylsubstituted)-cyclohex-1-ene carboxylic acids, 2-(4-phenylsubstituted)-benzene carboxylic acids, cis-3-and 4-substituted and trans-3- and 4-substituted cinnamic acids were correlated with a simple Hammett equation by means of the σp and σm constants and with an extended Hammett equation to detect the presence or absence of steric effects as well as the composition of the electrical effect. The transmission of polar effects through the different double bonds was discussed in terms of the polar susceptibility constant δ and steric interaction of the phenyl and carboxylic group.