Microwave assisted, Cu-catalyzed synthesis of sulfonamides using sodium sulfinates and amines

An efficient procedure has been developed under microwave irradiation for the monosulfonylation of amines in acetonitrile:water. In this reaction, equimolar quantities of amines and sodium sulfinates were reacted in presence of CuBr₂ and omitted the use of oxidants, ligands, additives, and bases. The developed methodology converts a wide array of sterically and electronically diverse sulfinate and amines into the corresponding sulfonamides in excellent yields within a short reaction time. The use of microwave and aqueous media makes this protocol potentially useful in the development of a green strategy for the synthesis of sulfonamides.