Reagent-controlled selective synthesis of sulfinamides and sulfoximines from tert-butanesulfinamide

The preparation of optically pure sulfinamides from tert-butanesulfinamide previously required multi-step sequences, involving both the incorporation of desired chemical fragments and the subsequent removal of the tert-butyl group from the sulfur center. Herein, we disclose a step-economic method that achieves these transformations in a single reaction. The formal tBu-to-Ar exchange reaction of tert-butanesulfinamide is accomplished using aryldiazonium reagents and a copper catalyst. Both the catalyst and additives are crucial for the success of this method. A slight modification of the reaction conditions results in the formation of tert-butanesulfoximines, which are likely the transient precursors of the tBu-to-Ar exchange, undergoing in situ debutylation to give sulfinamides.