Abstract
The acid catalysed formation of peracids from ω-phenyl and ω-phenoxy fatty acids (benzoic (I), phenylacetic (II), β-phenylpropionic (III), γ-phenylbutyric (IV), δ-phenylvaleric (V), phenoxyacetic (VI) and β-phenoxypropionic (VII) acids) has been studied kinetically in dioxane. The comparison of the second order rate constants indicated the rapid formation of the peracids from II, III, IV and VII. Plots of logarithms of the rate constants vs Taft's steric substituent constants show that the reaction is controlled by steric rather than polar effects. The activation parameters suggest the effect of benzene ring on the carboxyl group of II, which increases freedom of the transition state for the peracid formation.