Evaluation of the Catalytic Activity of H3PW12O40 in the Selective Oxidation of Sulfides to the Corresponding Sulfoxides or Sulfones

H3PW12O40 in bulk form presents suitable properties to be used as catalyst in the selective oxidation of sulfides with 35% aqueous hydrogen peroxide, and sulfoxides or sulfones were obtained as products in high to excellent yields and selectivity. We found that sulfides were oxidized to the corresponding sulfoxides, with near stoichiometric 35% w/V aqueous hydrogen peroxide, at room temperature (20°C) and with a catalytic amount of bulk H3PW12O40. Similarly, sulfides were transformed to the corresponding sulfones using excess of 35% w/V aqueous hydrogen peroxide and a temperature of 70°C. In both cases acetonitrile was used as reaction solvent.