Formation of the Tertiary Sulfonamide C(sp3)–N Bond Using Alkyl Boronic Ester via Intramolecular and Intermolecular Copper-Catalyzed Oxidative Cross-Coupling

A synthetic strategy for the formation of C­(sp3)–N bonds, particularly through a copper-catalyzed oxidative cross-coupling, is rare. Herein, we report a novel synthetic approach for the preparation of tertiary sulfonamides via copper-catalyzed intra- and intermolecular oxidative C­(sp3)–N cross-coupling reactions. This method allows the utilization of the readily available C­(sp3)-based pinacol boronate as a substrate and the tolerance of a wide range of functional groups under mild reaction conditions. The success of this strategy relies on the unprecedented additive effects of silanol and NaIO4.