Pd-catalyzed α-arylation of thioamides

Thioamides are unique and versatile synthetic building blocks with S, N, and α-C three adjacent nucleophile centers, however, they are rarely used as carbon nucleophiles for transition-metal-catalyzed C–C coupling reactions. This Letter describes the first Pd-catalyzed α-arylation of thioamides and demonstrated the feasibility of the application of thioamides in coupling chemistry. By the coupling process, a variety of α-arylated thioamides were prepared in moderate to good yields under mild reaction conditions, which provides an alternative way to access functionalized thioamides as well as a new synthetic transformation for thioamides. High chemoselectivity for thioamide over amide was observed in the reaction.