A New Reaction of 2-(Phenylsulfonyl)-3-phenyloxaziridine (Davis Reagent):  Oxidation of Thiolates to Sulfinates. Application to the Synthesis of Sulfones

The first efficient and general method for the generation of sulfinate anions by oxidation of the corresponding thiolates is described. The oxidizing agent employed is the classical 2-(phenylsulfonyl)-3-phenyloxaziridine, commonly known as the Davis reagent. Subsequent S-alkylation of the sulfinates under phase-transfer catalysis affords sulfones 6 in 71−91% isolated yields (10 examples).