Merging Cobalt-Catalyzed C-H Activation with the Mannich Reaction: A Modular Approach to α-Substituted N-Sulfonyl Amines.

A three-component synthesis of α-substituted N-sulfonyl amines from aryl aldehydes, primary sulfonamides, and (hetero)arenes is described. This transformation enables a straightforward and modular synthesis of highly substituted sulfonamide scaffolds in good yields. The direct functionalization of C(sp2)-H bonds via cobalt-catalyzed C-H-activation offers an appealing and atom-economical alternative to classical methods for the synthesis of α-arylated amines such as the Petasis or Mannich-type reactions.