Highly enantioselective amination of alpha-substituted alpha-cyanoacetates with chiral catalysts accessible from both quinine and quinidine.
[Reaction: see text] The catalytic construction of nitrogen-substituted quaternary stereocenters is an important and challenging task in asymmetric synthesis. In this paper, we describe the use of 6'-OH-modified cinchona alkaloids that are accessible from either quinine or quinidine for the development of a highly enantioselective amination of alpha,alpha-disubstituted carbonyl compounds that is suitable for the creation of nitrogen-substituted quaternary stereocenters in either the R or S configuration.
Liu
Xiaofeng
X
Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, USA.
Li
Hongming
H
Deng
Li
L