Pd‐Catalyzed ortho‐C−H Olefination of Benzenesulfonamides Directed by 7‐Azaindole

Demonstrated herein is a Pd-catalyzed ortho-C-H olefination of benzenesulfonamides using 7-azaindole as the directing group. This reaction proceeds with exclusive ortho selectivity, high efficiency and broad substrate scope. This method also provides access to sulfonic acids and ortho-alkylated sulfonamides. Control experiments provides some insightful evidences to the mechanism and the plausible catalytic cycle is proposed to go through a unique seven-membered palladacycle species.