Synthesis of β-lactams from β-amino acids using organophosphorous reagents

Abstract

β-Lactam formation via the dehydration of β-amino acids has been developed using organophosphosphorous condensing reagents, benzotriazolyloxytris [dimethylamino] phosphonium hexafluorophosphate (BOP) and triphenylphosphine/N-bromosuccinimide ($Ph_3P$/NBS) system. BOP reagent has been found to be exceedingly effective for the preparation of various β-lactams from β-amino acids. Especially, N-substituted β-amino acids give good yields and high dilution and high temperature are more favorable. Also, $Ph_3P$/NBS method include a successful application of a triphenylphosphine as a condensing agent for the formation of β-lactams from β-amino acids, easy separation of β-lactams from the reaction mixture, mild conditions and high yields in short time for N-substituted β-amino acids under low dilution.