Nickel-Catalyzed Reductive Arylation of N -Acyl Hemiaminals

N -Benzyl amides are important structural motifs in pharmaceuticals and natural products. The nucleophilic substitution reactions between aromatic nucleophiles and N -acyliminium ion precursors ( N -acyl hemiaminal derivatives) represent one of the most common and powerful approaches. However, these protocols are typically limited by the scope of aromatic substrates or the requirement for air-sensitive reagents. Herein, we report a nickel-catalyzed reductive arylation reaction between N -acyl hemiaminals and readily available aryl halides, which enables the synthesis of a series of structurally diverse N- benzyl amide derivatives under mild conditions through simple operations. Mechanistic studies support a nickel-catalyzed cross-coupling pathway mediated by an N -acyliminium ion intermediate and exclude the participation of an N -acyl α-aminoalkyl radical.