Dinitrogen Tetroxide Impregnated Activated Charcoal (N2O4/Charcoal): ­Selective Oxidation of Sulfides to Sulfoxides and Disulfides to Thiosulfonates

Abstract

Dinitrogen tetroxide was easily impregnated on activated charcoal to give a stable heterogeneous reagent (N 2 O 4 /charcoal). The chemoselective oxidation of sulfides to sulfoxides in the presence of different sensitive functional groups was achieved using this reagent in CH 2 Cl 2 at room temperature. Dialkyl sulfides were also selectively converted to their corresponding sulfoxides in the presence of diaryl or alkyl-aryl sulfides. Oxidation of disulfides to thiosulfonates without any over oxidation was also performed at room temperature by this system.