The reaction between hydrazines and β-dicarbonyl compounds:: proposal for a mechanism

被引：100

作者：

Singh, SP

Kumar, D

Batra, H

Naithani, R

Rozas, I

Elguero, J

机构：

[1] CSIC, Inst Quim Med, E-28006 Madrid, Spain

[2] Kurukshetra Univ, Dept Chem, Kurukshetra 136119, Haryana, India

来源：

CANADIAN JOURNAL OF CHEMISTRY | 2000年 / 78卷 / 08期

关键词：

hydrazines; 1,3-diketones; pyrazolines; pyrazoles; PM3; calculations;

D O I：

10.1139/cjc-78-8-1109

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The reaction between aryl or heteroarylhydrazines with fluorinated beta-diketones (CF3COCH2COR) yields a variety of 3-, 5-, and 3,5-trifluoromethylpyrazoles and 5-trifluoromethyl-5-hydroxy-Delta(2)-pyrazolines. Twenty-one of such compounds have been isolated and identified by C-13 and F-19 NMR. Together with the results from the literature they provide a comprehensive overview of the reaction. Semi-empirical calculations at the PM3 level have been used to rationalize these results. The outcome that emerges seems to be that the dehydration of a pair of 3,5-dihydroxypyrazolidines kinetically controls the isomer formed.

引用

页码：1109 / 1120

页数：12

共 32 条

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