A general procedure for the selective oxidation of sulfides to sulfoxides by nitric acid: tetrabromoaurate(III) catalyst in a biphasic system

Abstract

Tetrabromoaurate(III) is an efficient catalyst for the oxidn. of sulfides to sulfoxides by nitric acid in a biphasic system (nitromethane/water). The system is selective and can be applied to the oxidn. of any type of dialkyl and alkyl aryl sulfides and also of diaryl sulfides activated by electron-releasing substituents. The nature of the active species has been investigated in relation to the mechanistic aspects.