Electroreductive generation of (S)-(+)-N,N-dimethyl-2-(hydroxymethyl)-pyrrolidinium mercury compound for enantioselective synthesis of 2-amino-1-alkyl/aryl ethanols

摘要

(S)-(+)-N,N - Dimethyl-2-(hydroxymethyl)-pyrrolidinium (DMHP~+)-mercury compound mediated enantioselective reduction of aminomethyl alkyl/aryl ketones in dimethyl-formamide-2-propanol (9:1) has been carried out using tetra-butylammonium tetrafluoroborate as a supporting electrolyte.The products viz.2-amino-1-alkyl/aryl ethanols have been obtained in good yield (68-92%) with 35-91% optical purity and have been assigned (S)-configuration.The pinacol (racemic/meso) derivatives are also isolated as minor products (yield 5-20% ) via dimerization of radical anion followed by protonation.