Nano Silica Melamine Trisulfonic Acid as an Efficient and Reusable Heterogeneous Catalyst for the Synthesis of 5-Substituted-1H-Tetrazoles

A convenient method for the synthesis of 5-substituted-1H-tetrazoles from organic nitriles and sodium azide in the presence of nano silica melamine trisulfonic acid is reported. A series of aliphatic and aromatic nitriles underwent a [3+2] cycloaddition with sodium azide to afford tetrazoles in good to excellent yields and acceptable reaction times. The nano silica melamine trisulfonic acid is an efficient heterogeneous nanocatalyst with high catalytic performance. The nano silica melamine trisulfonic acid is readily prepared, environmentally friendly and reusable. The catalyst was characterized by powder X-ray diffraction, energy-dispersive X-ray mapping and SEM techniques. This simple and cost effective procedure could be promising for further applications in organic syntheses.