Selective oxidation of two dialkyl sulphides catalysed by ruthenium complexes

Abstract

Di-n-butyl and diethyl sulphide both undergo selective oxidation to the corresponding sulphoxide and sulphone on treatment with oxygen in ethanol in the presence of ruthenium(III) chloride. Some ruthenium complexes also catalyse the oxidation of di-n-butyl sulphide in benzene, but the extent and selectivity of the oxidation are much less than in ethanol. A non-radical mechanism seems to be the main pathway in both solvents, but no evidence for the involvement of a dioxygen complex has been obtained, and it is concluded that a redox mechanism is involved.