A simple procedure for the preparation of enantiopure ethyl α-hydroxyalkyl ketones
作者:Ricardo Martín、Oscar Pascual、Pedro Romea、Roser Rovira、Fèlix Urpí、Jaume Vilarrasa
DOI:10.1016/s0040-4039(97)00107-x
日期:1997.3
Amides derived from pyrrolidine and methyl (S)-lactate, methyl (S)-2-hydroxy-3-phenylpropanoate, or methyl (S)-2-hydroxy-3-methylbutanoate, after O-benzylation and O-silylation have been treated with EtLi or EtMgCl under suitable conditions, to give excellent overall yields of enantiopure ethyl ketones. The chelating ability of alpha-OBn amides (and even of alpha-O-TBS amides, which has been demonstrated by NMR to be better than that of N-OMe amides) accounts for the performance of the approach. (C) 1997 Elsevier Science Ltd.