期刊
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
卷 2006, 期 14, 页码 3235-3241出版社
WILEY-V C H VERLAG GMBH
DOI: 10.1002/ejoc.200600104
关键词
amino acids; cycloaddition; diastereoselectivity; nitrogen heterocycles
The diastereoselective synthesis of trans- and cis-4-hydroxypipecolic acids has been achieved with geometry-controlled nitrone cycloaddition chemistry. The cycloaddition of 3-butenol to enantiopure C-aminocarbonyl and C-alkoxycarbonyl nitrones having a definite (Z) and (E) configuration, respectively, occurs with complete regio- and exo selectivity. The acyclic (Z)-nitrone 12 affords two cycloadducts in a 1:1 ratio, which can be separated and converted into (2R,4R)- and (2S,4S)-4-hydroxypiperolic acids, respectively, in four steps, The cyclic (E)-nitrone 17 reacts with complete diastereofacial selectivity and the elaboration of its sole adduct gives the methyl ester of (2R,4S)-4- hydroxypip e colic acid, albeit in low yield. (c) Wiley-VCH Verlag GmbH & Co.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据