A New Method for the Synthesis of β-Amino Acid Derivatives and β-Lactams. Reaction of N-Alkoxycarbonyl-1-methoxyamines with Esters
摘要:
The reaction of N-alkoxycarbonyl-1-methoxyamines with esters is an alternative to the reaction of imines with esters for the synthesis of beta-amino acid derivatives. In this reaction, N-alkoxycarbony-1-methoxyamines corresponding to unstable imines can also be employed. Although anti adducts were obtained preferentially in the absence of Ti complexes, the diastereoselectivity of this reaction was reversed by the addition of Ti(OPr-i)(4). The obtained adducts were transformed to the corresponding beta-lactams.
Asymmetric Synthesis of <i>anti</i>-α,β-Disubstituted β-Amino Acid Derivatives by Reaction of <i>N</i>-Alkoxycarbonyl-1-methoxyamines with Optically Active 2-Oxazolidinones
作者:Naoki Kise、Nasuo Ueda
DOI:10.1021/ol991053s
日期:1999.12.1
[GRAPHICS]The reaction of N-alkoxycarbonyl-1-methoxyamines and (4S)-3-butyryl-4-isopropyl-2-oxazolidinone afforded the corresponding adducts with anti selectively (60% de). Both anti- and syn-alpha,beta-disubstituted beta amino acid methyl eaters were obtained in 98% ee from the adducts. The enantiomerically pure precursor for the synthesis of carbapenem antibiotic PS-5 was prepared by this method.