Asymmetric Mannich Reactions Catalyzed by a Dinuclear Nickel Complex

Significance

The authors report an anti-selective asymmetric Mannich reaction catalyzed by a dinuclear zinc Schiff base complex. N-Nosyl imines ­react with α-ketoanilides to give the Mannich products in excellent yields and diastereoselectivities. The products can be subjected to a stereo­selective reduction to afford anti-anti α-hydroxy β-alkyl γ-amino acids, which can then undergo a ­Mitsunobu reaction to form chiral azetidine-2-amides.