Abstract
The oxidation of thioglycollic, thiolactic and thiomalic acids by butyltriphenylphosphonium dichromate (BTPPD) in dimethylsulfoxide (DMSO) yielded the corresponding disulfide as the product. The reaction is first order with respect to BTPPD, however, second-order dependences of the rate were found on the concentrations of both the thioacid and hydrogen ions. The rate of oxidation of thiolactic acid (TLA) was determined in nineteen organic solvents. An analysis of the solvent effect by multiparametric equations indicated the cation-solvating power of the solvents to be most significant. A mechanism has been proposed involving the formation of a thioester in a pre-equilibrium, followed by its decomposition in the slow step.
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