Asymmetric Synthesis of α-Amino Phosphonic Acids by Diastereoselective Addition of Trimethyl Phosphite onto Chiral Oxazolidines

摘要

A simple and general asymmetric synthesis of α-amino phosphonic acids is described. The method involves the highly selective addition of trialkyl phosphite onto various chiral oxazolidines. Oxazaphosphorinanes thus obtained with an excellent diastereoselectivity furnish the corresponding (S)-α-substituted amino phosphonic acids in good overall yields and high ee (77→97%) after simple deprotection.