Synthesis of new 1,1’-di(4-nitro or 2-nitrophenyl)-5,5’-disubstituted-3,3’-bipyrazoles under microwave irradiation and classical heating conditions

Rachid Touzani,Abdelkrim Ramdani,Ibrahim Bouabdallah,Smaail Radi,Ismail Zidane

doi:10.3998/ark.5550190.0007.e07

Abstract

Ten new 1,1'-di(4-nitro or 2-nitrophenyl)-5,5'-disubstituted-3,3'-bipyrazoles have been prepared in one step by N,N-arylation of 5,5'-disubstituted-3,3'-bipyrazoles with 4-fluoro and 2- fluoronitrobenzene. The reaction was carried out under microwave irradiation for 5 min and under classical heating conditions for one to two hours, affording high yields of diarylbipyrazole derivatives.

Highlights

Since Claisen’s1, 2 synthesis, many bipyrazole derivatives have been prepared for biological, medical and industrial purposes. They have been found to possess antiinflammatory,[2,3,4] cytoxic[2,5] and anti-microbial[4] properties. They are useful as insecticides,[2,6] herbicides,[2,7] fungicides[2,8] and in the synthesis of heat resistant polymers.[9]
Other authors[10] reported bipyrazole derivatives as active components in capturing active oxygen and they are useful as agents for preventing or treating various diseases induced by active oxygen
We report two comparative approaches for the preparation of some new bipyrazole derivatives, by N,N-arylation reactions under microwave irradiation and classical heating conditions hoping to get improved catalytic and biologic activities

Summary

General Papers

Synthesis of new 1,1’-di(4-nitro or 2-nitrophenyl)-5,5’-disubstituted3,3’-bipyrazoles under microwave irradiation and classical heating conditions. Ibrahim Bouabdallah,a,* Rachid Touzani,a,b Ismail Zidane,a Abdelkrim Ramdani,a and Smaail Radia aLaboratoire de Chimie Organique Physique, Département de Chimie, Faculté des Sciences, Université Mohamed I er, BP 524, Oujda, Maroc bFaculté Pluridisciplinaire de Nador, Université Mohamed I er B.P. 300, 62700 Selouane, Nador, Maroc

Introduction

NN H

Microwave irradiation

Experimental Section