Catalytic enantioselective Strecker reaction of ketoimines
Shuji Masumoto1, Hiroyuki Usuda, Masato Suzuki
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan.
Abstract:
A new method for the catalytic enantioselective Strecker reaction (cyanation) of N-diphenylphosphinoyl ketoimines is described. The asymmetric catalyst is a chiral gadolinium complex prepared from Gd(OiPr)3 and the d-glucose-derived ligand 3 in a 1:2 ratio. The reaction has a broad substrate generality, giving high enantioselectivity from aromatic, ethyl, primary alkyl, and alpha,beta-unsaturated ketoimines. The products could be easily converted to disubstituted alpha-amino acids and their derivatives.
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