Asymmetric Mannich Reactions Catalyzed by a Dinuclear Nickel Complex
Y. Xu, G. Lu, S. Matsunaga*, M. Shibasaki*
The University of Tokyo, Japan
22. Juni 2009 (online)
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.