KINETICS AND MECHANISM OF OXIDATION OF SUBSTITUTED PHENYL METHYL SULPHIDES BY N-BROMOACETAMIDE

Article abstract of DOI:10.1016/S0040-4020(01)82068-8

The kinetics of oxidation of several substituted phenyl methyl sulphides by N-bromoacetamide (NBA) in 80percentacetonitrile-20percentwater (v/v) mixture are presented.The reaction is first order with respect to both sulphide and NBA and second order in Hg(II).The rate of the reaction exhibits inverse dependence on both and .Electron-releasing substituents present in the phenyl ring of the sulphides accelerate the rate while electron-withdrawing ones retard it.The results are in accord with a mechanism involving the reaction between NBA-Hg(II) and sulphide-Hg(II) complexes in the slow rate-limiting step affording a sulphonium ion which hydrolyses in a subsequent fast step to the sulphoxide.