Improved Synthesis of 5-Substituted 1H-Tetrazoles via the [3+2] Cycloaddition of Nitriles and Sodium Azide Catalyzed by Silica Sulfuric Acid

Zhenting Du,Yin Wang,Jing Lu,Changmei Si,Youqiang Li

doi:10.3390/ijms13044696

Abstract

A silica supported sulfuric acid catalyzed [3+2] cycloaddition of nitriles and sodium azide to form 5-substituted 1H-tetrazoles is described. The protocol can provide a series of 5-substituted 1H-tetrazoles using silica sulfuric acid from nitriles and sodium azide in DMF in 72%–95% yield.

Highlights

In recent years, the growth of the tetrazole chemistry has been significant [1,2], mainly as a result of the central roles played by tetrazoles in coordination chemistry as nitrogen-containing heterocyclic ligands [3], in materials applications as specialty explosives, information recording systems, rocket propellants and in agrichemical applications [4,5]
We are interested in an efficient and convenient formation of 5-substituted 1H-tetrazoles through nitrile and sodium azide catalyzed by silica sulfuric acid
To the best of our knowledge, there is no report on any solid acid catalytic synthesis of 5-substituted 1H-tetrazoles from nitrile and sodium azide

Summary

Introduction

The growth of the tetrazole chemistry has been significant [1,2], mainly as a result of the central roles played by tetrazoles in coordination chemistry as nitrogen-containing heterocyclic ligands [3], in materials applications as specialty explosives, information recording systems, rocket propellants and in agrichemical applications [4,5]. The proton acid-catalyzed cycloaddition between hydrazoic acid and nitriles has long been one of the main routes to 5-substituted tetrazoles. This standard procedure suffers a dangerous potential explosion with large excess amounts of harmful hydrazoic acid [13]. We are interested in an efficient and convenient formation of 5-substituted 1H-tetrazoles through nitrile and sodium azide catalyzed by silica sulfuric acid. To the best of our knowledge, there is no report on any solid acid catalytic synthesis of 5-substituted 1H-tetrazoles from nitrile and sodium azide. We wish to report a facile synthesis of 5-substituted 1H-tetrazoles catalyzed by silica sulfuric acid in 72–95% yield

Results and Discussion

Experimental Section

Conclusions