Cp*Co(III)-Catalyzed ortho-C-H Alkynylation of Pivalanilides with Bromoalkynes

A straightforward and efficient Cp*Co(III)-catalyzed ortho-C-H alkynylation of anilides with diverse readily available bromoalkynes was developed in which the weakly coordinating amide carbonyl group served as the directing group. This strategy provides a practical route for the synthesis of ortho-alkynylanilines, featuring good functional group tolerance and a broad substrate scope. Aryl-, alkyl-, and silyl-substituted bromoalkynes are compatible substrates in this catalytic system. Furthermore, subsequent synthetic transformations of the products demonstrate the synthetic utility of this methodology.