Ligand-Promoted Rhodium(III)-Catalyzed ortho-C-H Amination with Free Amines.

Ligand development for rhodium(III)-catalyzed C-H activation reactions has largely been limited to cyclopentadienyl (Cp) based scaffolds. 2-Methylquinoline has now been identified as a feasible ligand that can coordinate to the metal center of Cp*RhCl to accelerate the cleavage of the C-H bond of N-pentafluorophenylbenzamides, providing a new structural lead for ligand design. The compatibility of this reaction with secondary free amines and anilines also overcomes the limitations of palladium(II)-catalyzed C-H amination reactions.