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

共 27 条

[11]

CURRAN DP, 1988, ADV CYCLOADDITION, V1, P129

[12]

DALCONTRES GS, 1950, GAZZ CHIM ITAL, V80, P41

[13] New developments in the chemistry of low-valent titanium [J].

Furstner, A ;

Bogdanovic, B .

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1996, 35 (21) :2442-2469

[14] Reagent-controlled transition-metal-catalyzed radical reactions [J].

Gansäuer, A ;

Bluhm, H .

CHEMICAL REVIEWS, 2000, 100 (08) :2771-2788

[15]

Ignatovich Zh.V., 1999, CHEM HETEROCYCL COMP, P248

[16]

Kotyatkina A. I., 2001, RUSS CHEM REV, V70, P641, DOI DOI 10.1070/RC2001V070N08ABEH000630

[17] THE ISOXAZOLINE ROUTE TO THE MOLECULES OF NATURE [J].

KOZIKOWSKI, AP .

ACCOUNTS OF CHEMICAL RESEARCH, 1984, 17 (12) :410-416

[18]

Kulinkovich O. G., 1991, J ORG CHEM USSR, V27, p[294, 250]

[19] TITANIUM(IV) ISOPROPOXIDE-CATALYZED FORMATION OF 1-SUBSTITUTED CYCLOPROPANOLS IN THE REACTION OF ETHYLMAGNESIUM BROMIDE WITH METHYL ALKANECARBOXYLATES [J].

KULINKOVICH, OG ;

SVIRIDOV, SV ;

VASILEVSKI, DA .

SYNTHESIS-STUTTGART, 1991, (03) :234-234

[20]

LAKHVICH FA, 1989, CHEM HETEROCYCL COMP, P359

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