Rh(III)-Catalyzed C-H Cyanation of 2-Indazole with -Cyano--phenyl--toluenesulfonamide.

A Rh(III)-catalyzed direct cyanation of 2-indazoles with -cyano--phenyl--toluenesulfonamide has been realized via a chelation-assisted strategy. The methodology enables regioselective access to various ortho-cyanated phenylindazoles in good yields with a broad substrate scope and good functional group compatibility. The obtained cyanated indazoles could further be converted into other value-added chemicals. Importantly, the current protocol is featured with several characteristics, including a novel cyanating agent, good regioselectivity, and operational convenience.