Formal Asymmetric Biocatalytic Reductive Animation

摘要

Asymmetric methods to prepare optically active a-chiral primary amines are highly demanded in asymmetric synthesis owing to the biological/pharmacological activity of many amines.Various techniques have been reported,such as asymmetric 1,2-addition to imines and asymmetric amination of a,a-disubstituted aldehydes,transformation of allylic alcohols into amines,(dynamic)kinetic resolution,and cyclic deracemization employing racemic amines as substrates.Asymmetric reductive amination of ketones has been investigated with transition-metal catalysts and organo-catalysts,as well as via sulfinyl imine intermediates.Although tremendous progress in organo/metal catalysis has been achieved for the asymmetric reductive amination of ketones to access alpha-chiral amines,improved protocols are still required that are simple,green,and economically viable and that lead to high enantiomeric excesses.