Addition of tert-butylcuprate to (2S)-N-acyl-Δ5-dehydroprolinates as a diastereoselective synthetic procedure for obtaining (2S,5S)-5-tert-butylproline
作者:E WALLEN、J CHRISTIAANS、J GYNTHER、J VEPSALAINEN
DOI:10.1016/s0040-4039(03)00169-2
日期:2003.3.3
The synthesis of (2S,5S)-Boc-5-tert-butylproline ethyl ester via the addition of tert-butylcuprate to (2S)-N-Boc-Delta(5)-dehydroproline ethyl ester, formed from (2S)-N-Boc-5-methoxyproline ethyl ester, gives an excellent yield of 94% and a high diastereoselectivity (2S,5S):(2S,5R) 78:22. This synthesis opens up a new synthetic route to (2S,5S)-5-tert-butylproline, which is a useful, conformationally rigid, analogue of L-proline. (C) 2003 Elsevier Science Ltd. All rights reserved.