Tuning of Chemo- and Regioselectivities in Multicomponent Condensations of 5-Aminopyrazoles, Dimedone, and Aldehydes
作者:Valentin A. Chebanov、Vyacheslav E. Saraev、Sergey M. Desenko、Vitaliy N. Chernenko、Irina V. Knyazeva、Ulrich Groth、Toma N. Glasnov、C. Oliver Kappe
DOI:10.1021/jo800825c
日期:2008.7.1
Regio- and chemoselective multicomponent protocols for the synthesis of 1,4,6,7,8,9-hexahydro-1H-pyrazolo[3,4-b]quinolin-5-ones, 5,6,7,9-tetrahydropyrazolo[5,1-b]quinazolin-8-ones, and 5a-hydroxy-4,5,5a,6,7,8-hexahydropyrazolo[4,3-c]quinolizin-9-ones starting from 5-amino-3-phenylpyrazole, cyclic 1,3-dicarbonyl compounds and aromatic aldehydes are described. Whereas the three-component coupling in
区域和化学选择性多组分方案用于合成1,4,6,7,8,9-六氢-1 H-吡唑并[3,4- b ]喹啉-5-酮,5,6,7,9-四氢吡唑并[5,1- b ] quinazolin-8-ones和5a-hydroxy-4,5,5a,6,7,8-hexahydropyrazolo [4,3- c描述了从5-氨基-3-苯基吡唑,环状1,3-二羰基化合物和芳族醛开始的] quinolizin-9-one。乙醇在回流条件下的三组分偶合提供了吡唑并喹啉酮和吡唑并喹唑啉酮的混合物,在三乙胺碱存在的情况下,通过在150°C的条件下进行密封反应,可以将反应成功地朝着吡唑并喹啉酮(Hantzsch型二氢吡啶)的方向进行调节。容器微波或常规加热。另一方面,在室温下在中性条件下使用超声处理有利于形成吡唑并喹唑啉酮异构体(Biginelli型二氢嘧啶)。当在三甲基甲硅烷基氯作为反应介质的情况下在高温下进行三组分缩合时