N-Protecting group tuning of the enantioselectivity in Strecker reactions of trifluoromethyl ketimines to synthesize quaternary α-trifluoromethyl amino nitriles by ion pair catalysis†
Abstract
An enantioselective Strecker reaction to construct trifluoromethylated quaternary stereocenters with N-PMP and unexplored N-Boc trifluoromethyl ketimines catalyzed using an organophosphine dual-reagent catalyst has been developed. The enantioselectivities of the corresponding products with the same catalyst could be switched by using different N-protecting groups (N-PMP or N-Boc). The trifluoromethyl amino nitriles were obtained in high yield and high enantioselectivity in a short time and could be easily converted to a variety of useful trifluoromethyl-containing compounds.