Microwave irradiation in solvent-free conditions:: an eco-friendly methodology to prepare indazoles, pyrazolopyridines and bipyrazoles by cycloaddition reactions

被引：74
作者：
Díaz-Ortiz, A
de la Hoz, A
Langa, F
机构：
[1] Univ Castilla La Mancha, Fac Quim, E-13071 Ciudad Real, Spain
[2] Univ Castilla La Mancha, Fac Ciencias Medioambiente, Toledo 45001, Spain
来源：
GREEN CHEMISTRY | 2000年 / 2卷 / 04期
关键词：
D O I：
10.1039/b003752o
中图分类号：
O6 [化学];
学科分类号：
0703 ;
摘要：
A study on the behaviour of vinylpyrazoles, pyrazolyl imines and pyrazolyl hydrazones as dienes or dipoles is reported. Cycloaddition of the aforementioned compounds with electron-poor reagents under microwave irradiation in solvent-free conditions permits the preparation of indazoles, pyrazolopyridines and bipyrazoles in moderate to good yields. This represents an eco-friendly, green approach to these valuable pyrazole derivatives that avoids the harsh or highly contaminant conditions involving classical heating and offers a reduction or even elimination of solvent use and recovery, simplification of the work up procedures, facility of scale up and savings in energy consumption, in addition with higher yields.
引用
收藏
页码：165 / 172
页数：8
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