Oxygenation of organic sulfides catalyzed by simple Fe(III) salts

Organic sulfide oxygenation by hydrogen peroxide (H2O2) was effectively accomplished by using iron(III) chloride or iron(III) bromide as the catalyst. The distribution of products between sulfoxide and sulfone is strongly solvent-dependent, and a 100% selectivity for sulfoxide was achieved with FeCl3 in a 1:1 methanol/water mixture.