Oxidation Kinetics and Mechanistic Studies of Thioacids by Imidazolium Dichromate

Abstract

We have studied three thioacids(TA) namely; thio-glycollic(TGA), thio-lactic(TLA) and thio-malic(TMA) acid by imidazoliumdichromate (IDC) in dimethyl-sulphoxide (DMSO). Oxidation of these thio-acids leads to the formation of di-sulphide di-mmers. The reaction is having a unit order with the IDC. A fractional-order reaction was found w.r.t. TA. Test for free radical was not observed in this reaction. The influence of acidity was observed, which indicated the increase in the rate by the addition of acid. The study of oxidation of TLA was done in various nonaqueous media, and the influence of solvent media was examined by using some multi-parametric equation models. We postulate a mechanism in which a thio-eater is formed, which is decomposing in the rate-determining slow step.