Engaging Sulfonamides: Intramolecular Cross-Electrophile Coupling Reaction of Sulfonamides with Alkyl Chlorides.

The application of amine derivatives as coupling partners is rare due to the inherent strength of the C-N bond. Herein, we report the first cross-electrophile coupling reaction of unstrained benzylic sulfonamides. Nickel-catalyzed intramolecular cross-electrophile coupling reactions of acyclic and cyclic benzylic sulfonamides with pendant alkyl chlorides generate cyclopropane products. Mechanistic experiments and DFT calculations are consistent with initiation of the reaction by magnesium iodide accelerated oxidative addition of the benzylic sulfonamide. This work establishes neutral and unstrained amine derivatives as XEC partners, furnishes structural rearrangement of benzylic sulfonamides, and provides valuable information regarding catalyst design for the development of new cross-electrophile coupling reactions of carbon-heteroatom bonds.