Magnesium bromide diethyl etherate mediated highly diastereoselective aldol reaction between an aldehyde and a silyl enol ether

被引：21

作者：

Fujisawa, H ^{[1
]}

Sasaki, Y ^{[1
]}

Mukaiyama, T ^{[1
]}

机构：

[1] Sci Univ Tokyo, Fac Sci, Dept Appl Chem, Shinjyuku Ku, Tokyo 1628601, Japan

来源：

CHEMISTRY LETTERS | 2001年 / 03期

关键词：

D O I：

10.1246/cl.2001.190

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

High yield and excellent diastereoselectivity in the formation of methyl (2R,3R,5R,6S)-2,6-dibenzyloxy-7-(t-butyldimethylsiloxy)-3-hydroxy-5-(4-methoxybenzyloxy)-4,4-dimethylheptanoate 3 and methyl (2R,3R,4S)-2,4-dibenzyloxy-3-hydroxypentanoate 7 are achieved by aldol reaction between (Z)-2-benzyloxy-1-methoxy-1-(trimethylsiloxy)ethene 1 and chiral alkoxy aldehydes using three equivalents of MgBr2. OEt2. The following mechanism of the above aldol reaction proposes that MgBr2. OEt2 activated both chiral alkoxy aldehydes and silyl enolate, that is, magnesiumu enolate, formed by transmetalation from silyl enolate and MgBr2. OEt2, reacted with MgBr2. OEt2-chelated alkoxy aldehydes via the six-membered cyclic transition state.

引用

页码：190 / 191

页数：2

共 18 条

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