Dynamic kinetic resolution utilizing 2-oxoimidazolidine-4-carboxylate as a chiral auxiliary: Stereoselective synthesis of α-amino acids by Gabriel reaction
摘要:
A Highly stereoselective Gabriel reaction via dynamic kinetic resolution utilizing 2-oxoimidazolidine-4-carboxylate as a chiral auxiliary was exploited. The reaction of tert-butyl (4S)-1-methyl-3-(2-bromopropionyl)-2-oxoimidazolidine-4- carboxylate (2a) with potassium phthalimide at room temperature predominantly afforded tert-butyl (4S)-1-methyl-3-((2S)-2-(phthaloylamino)propionyl)-2- oxoimidazolidine-4-carboxylate ((S,S)-5a) in a good yield which was derived to L-alanine derivative (7) by removal of the chiral auxiliary. Copyright (C) 1996 Elsevier Science Ltd.