Chiral bipyridine/phenanthroline ligands have been applied as a class of unique ligands due to their rich coordination chemistry in the catalysis. Herein, we synthesize 13 new C2-symmetric chiral phenanthroline-bipyrroloimidazolone ligands (Phen-BPI) and 5 new C2-symmetric chiral bipyridine-bipyrroloimidazolone ligands (BPy-BPI). These Bpy/Phen-BPI pincer ligands performed successfully in nickel-catalyzed asymmetric Friedel-Crafts alkylation of indoles with 2-enoylpyridine-1-oxides, affording the chiral products with up to 93% yield and 99% ee. Control experiment and metal complex L1-Ni crystal supported the dual activation manner, in which the tridentate Bpy/Phen-BPI ligand contained two nitrogen atoms of pyridine unit and one tertiary amine group of the pyrroloimidazolone moiety coordinating with Ni(II) to activate the 2-enoylpyridine-1-oxides, and the tertiary amine group of the additional pyrroloimidazolone moiety as the H-bond acceptor activated the indoles through a NH-bonding interaction, resulting in the asymmetric transformation. This represented the first example showing that Bpy/Phen ligand contained three nitrogen atoms coordinating with the metal, and the additional nitrogen atom acted as the H-bond acceptor.

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