期刊
TETRAHEDRON
卷 63, 期 30, 页码 7178-7186出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.tet.2007.04.092
关键词
asymmetric synthesis; 3,4-dihydroisocoumarin; oxazoline; lateral lithiation; diastereomer-selective lactonization; silica gel
Reaction of the laterally lithiated (S)-4-isopropyl-2-(2-methoxy-6-methylphenyl) oxazoline with p-tolualdehyde gave an inseparable mixture of the addition products in low diastereoselectivity. However, the (S, S)-product cyclized to the corresponding 3,4-dihydroisocoumarin faster than the (S, R)-product on silica gel, which allowed to be produced both enantiomers of 8-methoxy-3-(p-tolyl)-3,4-dihydroisocoumarin in moderate to good optical purity [S-enantiomer: 75% ee; R-enantiomer: 96% ee]. This procedure was applied to the short-step synthesis of optically active 3,4-dihydroisocoumarin natural products such as (R)-8-hydroxy-3-(1-tridecyl)-3,4-dihydroisocoumarin and (R)-phyllodulcin. (C) 2007 Elsevier Ltd. All rights reserved.
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