Enantioselective Synthesis of Chiral 2‐Nitroallylic Amines via Cooperative Cation‐Binding Catalysis

Abstract

AbstractChiral allylic amines are valuable building blocks for biologically important compounds and natural products. In this study, we present the use of cooperative cation‐binding catalysis as an efficient method for synthesizing chiral allylic amines. By utilizing a chiral oligoEG and potassium fluoride as a cation‐binding catalyst and base, respectively, a wide range of biologically relevant chiral 2‐nitroallylic amines are obtained with excellent enantioselectivities (up to >99 % ee) through the organocatalytic asymmetric aza‐Henry‐like reaction of β‐monosubstituted and β,β‐disubstituted nitroalkenes with α‐amidosulfones as imine precursors. Extensive experimental studies are presented to illustrate plausible mechanisms. Preliminary use of a chiral 2‐nitroallylic amine as a Michael acceptor demonstrated its potential application for diversity‐oriented synthesis of bioactive compounds.