Copper-Catalyzed Asymmetric Nitro-Mannich Reactions
J. C. Anderson*, G. P. Howell, R. M. Lawrence, C. S. Wilson
University of Nottingham, UK
23 September 2005 (online)
This Cu(II)-catalyzed nitro-Mannich reaction afforded anti-β-nitroamines from p-methoxybenzylimines and TMS-nitropropanate. The products were obtained with generally good to excellent enantio- and diastereoselectivity and in good yields by using Cu(OTf)2 and a tert-Bu-BOX ligand. A range of aryl, heteroaryl and alkyl aldimines worked well under these conditions. The product can be readily converted into synthetically useful 1,2-diamines through a SmI2 reduction in good yield.