meta‐C−H Arylation and Alkylation of Benzylsulfonamide Enabled by a Palladium(II)/Isoquinoline Catalyst

Palladium(II)‐catalyzed meta ‐C−H arylation and alkylation of benzylsulfonamide using 2‐carbomethoxynorbornene (NBE‐CO₂Me) as a transient mediator are realized by using a newly developed electron‐deficient directing group and isoquinoline as a ligand. This protocol features broad substrate scope and excellent functional‐group tolerance. The meta ‐substituted benyzlsulfonamides can be readily transformed into sodium sulfonates, sulfonate esters, and sulfonamides, as well as styrenes by Julia‐type olefination. The unique impact of the isoquinoline ligand underscores the importance of subtle matching between ligands and the directing groups.