Cu(ii) immobilized on aminated epichlorohydrin activated silica (CAES): as a new, green and efficient nanocatalyst for preparation of 5-substituted-1H-tetrazolesElectronic supplementary information (ESI) available. See DOI: 10.1039/c4ra15148h

Cu( ii ) immobilized on aminated epichlorohydrin activated silica (CAES) is a novel and efficient heterogeneous nanocatalyst in the [3 + 2] cycloaddition reactions of various organic nitriles with sodium azide. The protocol can provide a series of 5-substituted-1 H -tetrazoles under mild conditions in DMSO. Efficient transformation, mild reaction conditions, easy product isolation and the potential reusability of the catalyst are attractive features. The catalyst (CAES) was characterized by FT-IR, TGA, TEM, BET, SEM-EDS, CHN and ICP techniques. Reusable nanocatalyst was prepared and characterized an efficient and environmentally benign method of 5-substituted-1 H -tetrazole synthesis was introduced.