Direct N[sbnd]H heteroarylation of NH-sulfoximines under electrochemical conditions

Abstract

Given the pivotal importance of sulfoximines in the field of medicine, they have garnered considerable attention in synthetic chemistry, and the development of novel catalytic methods to achieve their functionalization is highly valuable. Herein, a direct and practical electrochemical strategy for the synthesis of heteroaromatic-substituted products was developed using NH-sulfoximines and quinoxalin-2(1H)-ones as starting materials. The direct construction of the NC(sp2) bonds of NH-sulfoximines is achieved through the cleavage of the C3H bonds of quinoxalin-2(1H)-ones. This protocol features good functional group tolerance, simplicity in operation, and easy to scalability. By utilizing this electrochemical strategy, the structural modification of biomolecular derivatives has been successfully carried out, which is unattainable with other traditional oxidants. The mechanistic investigation demonstrates that quinoxalin-2(1H)-ones serve dual roles as both substrates and redox mediators, thereby avoiding the addition of extra hydrogen atom transfer (HAT) reagents.