A kinetic and mechanistic study of oxidation of N-Acetyl-DL-Methionine by pyridinium chlorochromate in aqueous DMF medium

The Kinetics of Oxidative transformation of N-Acetyl-DL-Methionine by pyridinium chlorochromate in aqueous DMF medium, containing perchloric acid has been studied at 40 ℃. The rate of reaction was found to be of first order dependence on PCC, N-Acetyl-DL-Methionine, and H+ ion Concentration. Michaelis–Menten type kinetics is observed respect to substrate. The increase in the rate of reaction with increase in acidity indicates the involvement of a protonated chromium(VI) species in the rate-determining step. The product of oxidation has been identified as N-Acetyl-DL-Methionine sulfoxide. The rate of reaction increased with increase in dielectric constant of the reaction medium. The activation parameters have been evaluated. On the basis of the experimental findings, a suitable mechanism and rate law has been proposed.