Selective Oxidation of Sulfides to Sulfones by H2O2 Catalyzed by Fe-Substituted Sandwich Type Polyoxometalate

Abstract

Catalytic activity of the sandwich-type heteropolytungstates ([(XW9O39)M4](n−m)−, where X = P, Si, As and M = Mn, Fe, Co, Ni, Cu and Zn) in the selective oxidation of sulfides to corresponding sulfone with aqueous H2O2 have been studied in acetonitrile. In comparison, different sandwich type polyoxometalates with various transition metals substituted and heteroatoms, TBAPWFe was found to be more active to each other’s. This catalyst with 2.5 equivalent of hydrogen peroxide, converted various sulfides to the corresponding sulfone with 96.8–99 % selectivity at 94–97 % conversion. Furthermore, for oxidizing various sulfides to the corresponding sulfone, the sulfide function is highly reactive and other functional groups such as the double bond and hydroxyl group are tolerable. This catalyst indicated very good reusability in the oxidation reaction.