SELECTIVE OXIDATION OF SULFIDES TO SULFOXIDES WITH MOLECULAR-OXYGEN CATALYZED BY N-HYDROXYPHTHALIMIDE (NHPI) IN THE PRESENCE OF ALCOHOLS

Aerobic oxidation of various sulfides using N-hydroxyphthalimide (NHPI ) in the presence of alcohols was examined. For instance, the oxidatio n of diphenyl sulfide in the presence of cyclohexanol and a catalytic amount of NHPI in benzonitrile gave diphenyl sulfoxide in 88 % yield a long with a small amount of diphenyl sulfone (7 %). The actual oxidant in this oxidation is considered to be an a-hydroxy hydroperoxide gene rated by the autoxidation of alcohol assisted by the NHPI which serves as the radical catalyst. (C) 1998 Elsevier Science Ltd. All rights re served.