Rhodium-catalyzed direct C-H amidation of azobenzenes with sulfonyl azides: a synthetic route to sterically hindered ortho-substituted aromatic azo compounds.

A rhodium(III)-catalyzed direct ortho-amidation of azobenzenes with sulfonyl azides as the amino source is disclosed. This reaction exhibits a broad substrate scope, high functional group tolerance, and regioselectivity, providing a variety of sterically hindered ortho-substituted azobenzene derivatives in good to excellent yield.