KINETICS AND CORRELATION ANALYSIS OF REACTIVITY IN OXIDATION OF ORGANIC SULPHIDES BY BENZIMIDAZOLIUM DICHROMATE

摘要

Kinetics and correlation analysis of reactivity in the oxidation of some monosubstituted aryl methyl sulphides by benzimidazolium dichromate were carried out in organic non-aqueous solvents. The reactions were of first order with respect to BIDC. However, the Michaelis-Menten type kinetics was observed with respect to sulphide. The reaction is catalysed by hydrogen ions and the order is less than one. An intermediate of composition sulphide-BIDC-H+ has envisaged. Based on kinetic data, analyses of the solvent effect and results of structure reactivity correlation along with some non-kinetic parameters, a mechanism involving rate-determining oxygen atom transfer in complex, formed by a nucleophilic attack of sulphide sulphur on BIDCH+ in a rapid pre-equilibrium, is suggested to give the corresponding sulphoxide via a cyclic transition state.