Stereocontrolled aldol reaction of N-acylpyrazoles with aldehydes using LDA or MgBr2-DIEA

被引：18

作者：

Kashima, C ^{[1
]}

Fukuchi, I ^{[1
]}

Takahashi, K ^{[1
]}

Fukusaka, K ^{[1
]}

Hosomi, A ^{[1
]}

机构：

[1] Univ Tsukuba, Dept Chem, Ibaraki, Osaka 305, Japan

来源：

HETEROCYCLES | 1998年 / 47卷 / 01期

关键词：

D O I：

10.3987/COM-97-S(N)31

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The aldol reaction of 1-acyl-3,5-dimethylpyrazoles (1) was kinetically controlled with syn stereoselectivity through lithium enolate intermediate using LDA. On the contrary, the anti stereoselective aldol reaction of 1 was caused by the action of DIEA in the presence of MgBr2 under the thermodynamic control. in the formation of syn-aldol products using 3-phenyl-1-menthopyrazole as a chiral auxiliary, the diastereoselectivity was observed up to 81% de with the predominant configuration of 2'S form.

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页码：357 / 365

页数：9

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