Chiral Biaryl N-Heterocyclic Carbene-Palladium Catalysts with Anagostic C-H<middle dot><middle dot><middle dot>Pd Interaction for Enantioselective Desymmetric C-N Cross-Coupling

Novel chiral biaryl imidazo[1,5-a]pyridine carbene-palladium complexes (ImPy-Pd) featuring an anagostic C-H<middle dot><middle dot><middle dot>Pd interaction and a C5-aryl substituent have been developed and successfully applied to the Pd-catalyzed enantioselective desymmetric C-N cross-coupling of malonamide derivatives, providing chiral 3,4-dihydroquinoline-2-ones with quaternary stereocenters in high yields (<= 99%) and enantioselectivities (<= 97:3 er). The chiral catalyst exerts stereocontrol by restricting the rotation of substituents around the metal center through anagostic interactions with sterically bulky substituents.