Unimolecular and bimolecular mechanisms in the acid-catalysed hydrolysis of methyl esters of aliphatic monocarboxylic acids in aqueous sulphuric acid

Abstract

Methyl esters of aliphatic carboxylic acids are shown to hydrolyse by the A_Ac2 mechanism in 76·88% sulphuric acid and, with the exception of those containing halogens, by the A_Ac1 mechanism in 95·90% sulphuric acid. The Taft equation, log (k/k₀)=σ*ρ*+E_s, using E_s values obtained from kinetic data in dilute acid, gives linear plots in each case.