Synthesis of Sulfoximines by Cu‐Catalyzed <i>S</i> ‐Arylation of Sulfinamides with Triarylboroxines

Abstract S ‐Arylation and S ‐alkenylation reactions of sulfinamides to synthesize sulfoximines have been developed. Previous S ‐arylation reactions require less accessible arylating agents, expensive catalysts, and potentially explosive oxidants under heating conditions. On the other hand, the present reaction can be performed with readily available triaryl and trialkenylboroxines, an inexpensive copper catalyst, and less hazardous air or oxygen as oxidant. In addition, the reaction proceeds under mild conditions at room temperature. This stereospecific reaction can convert optically pure sulfinamides to sulfoximines without racemization.