Amberlyst-15 catalyzed synthesis of 5-substituted 1-H-tetrazole via [3+2] cycloaddition of nitriles and sodium azide

A mild and efficient method for the preparation of 5-substituted 1-H-tetrazole derivatives is reported using solid acidic resin Amberlyst-15 as an effective heterogeneous catalyst. This method is advantageous because of non-toxicity and stability of catalyst, high product yield, simple methodology, and easy work up. The catalyst was recovered by simple filtration and reused several times delivering moderate to good product yield.