A relaxation study of the isomerisation of 2,2,3-trimethyl-levulinic acid

Abstract

Temperature-jump measurements on buffer solutions of 2,2,3-trimethyl-levulinic acid have been used to determine the rate of interconversion of its ring and chain isomers, and the results have been compared with those for similar systems. The consistency of the results confirms the validity of the method previously used for estimating the position of ring–chain equilibria in solutions of these compounds, based on a comparison of conventional pK values with acid–base catalytic power. Some qualitative information was obtained for the isomerisation of 2-acetylbenzoic acid, but no relaxation process could be detected for 2,2-dimethyl-levulinic acid, probably because the relevant enthalpy change is too small.