Metal catalysis in oxidation by peroxides. 30. Electrophilic oxygen transfer from anionic, coordinatively saturated molybdenum peroxo complexes

Abstract

Two anionic and coordinatively saturated oxodiperoxomolybdenum complexes, [MoO(O2)2L]-Bu4N+ (L = C6H4NCO-2 or C5H4N(O)CO-2), have been used as oxidants for a series of organic sulfides and sulfoxides in DCE. Quantitative yields of sulfoxides and sulfones, respectively, have been obtained. Spectroscopic (1H and 13C NMR) and kinetic evidence rule out any coordination process between the substrate and the oxidant requiring the formation of an unsaturated site on the metal. The data collected point to an oxidation mechanism involving a bimolecular reaction. This, at least for sulfide oxidations, appears to proceed through an electrophilic oxygen transfer from the peroxo complex to the substrate. © 1988, American Chemical Society. All rights reserved.