A convenient and, chemoselective method for the reductive ring cleavage of isoxazoles and isoxazolines with EtMgBr/Ti(Oi-Pr)4 reagent

被引：31

作者：

Churykau, DH ^{[1
]}

Zinovich, VG ^{[1
]}

Kulinkovich, OG ^{[1
]}

机构：

[1] Belarusian State Univ, Dept Organ Chem, Minsk 220050, BELARUS

来源：

SYNLETT | 2004年 / 11期

关键词：

low valent titanium; Grignard reagents; isoxazoles; isoxazolines; reduction;

D O I：

10.1055/s-2004-831294

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The interaction of 3,5-disubstituted isoxazoles and isoxazolines with low-valent titanium isopropoxide reagent, prepared by treatment of Ti(Oi-Pr)(4) with one equivalent of EtMgBr in diethyl ether, leads to the reductive cleavage of the five-membered heterocycle to afford the corresponding beta-enaminoketones and beta-hydroxyketones. The reaction proceeds smoothly with isoxazoline derivatives bearing alkynyl, hydroxymethyl, diethylacetal, acetyl, alkoxycarbonyl, alkylthiomethyl or alkylsulfonylmethyl substituents.

引用

页码：1949 / 1952

页数：4

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