Cp*Rh(III)-Catalyzed Regioselective C(sp2)–H Mono- and Dialkynylation of Thioamides by Sulfur Coordination

An efficient Cp*Rh(III)-catalyzed regioselective C(sp2)–H mono- and dialkynylation of thioamides was described. This reaction was performed under mild conditions in high yields (up to 98%) with a broad substrate scope. Significantly, the versatility of this method was further demonstrated by controlled mono- and dialkynylation. Application of this protocol in the late stage functionalization of two drug molecules (Adapalene and Amoxapine) was also demonstrated.