Facile and mild synthesis of 1-substituted-1H-1,2,3,4-tetrazoles catalyzed by methanesulfonic acid under solvent-free conditions

Methanesulfonic acid (MSA) was found to be an efficient catalyst for the synthesis of 1-substituted-1H-1,2,3,4-tetrazoles. A series of 1-substituted tetrazole compounds were synthesized from the reaction of various primary amines, sodium azide and triethyl orthoformate in the presence of catalytic amounts of MSA at room temperature. In this protocol, some of the tetrazole derivatives were synthesized in good to excellent yields and convenient reaction times. This method has the advantages of simple methodology and easy work-up.