Rimkus Audrius, Sewald Norbert
Faculty of Chemistry, University of Bielefeld, PO Box 10 01 31, D-33501 Bielefeld, Germany.
Org Lett. 2003 Jan 9;5(1):79-80. doi: 10.1021/ol027252k.
The enantioselective conjugate addition of diethylzinc to the activated nitroolefin methyl 3-nitropropenoate is efficiently catalyzed by copper(I) complexes with BINOL-based enantiopure phosphoramidite ligands. The nitroolefin moiety acts as the predominant Michael acceptor, giving rise to the unambiguous formation of 2-alkyl-3-nitro-propanoates. Moderate to excellent enantioselectivities and high chemical yields are obtained. The product can easily be transformed into a beta(2)-homoamino acid. [reaction--see text]