A versatile and an efficient synthesis of 5-​substituted-​1H-​tetrazoles

A simple, efficient and a versatile method for the synthesis of 5-​substituted-​1H-​tetrazoles by a [3+2]​-​cycloaddn. reaction of aryl nitriles with sodium azide in DMF using ZrOCl2·8 H2O as catalyst has been developed. The reactions work well at 100°C and give the desired products in excellent yield. The examples studied include arom. nitriles having electron donating as well as electron releasing groups on the arene nucleus