Table 3 Synthesis of 1-substituted 1H-1,2,3,4-tetrazole derivatives using Co–Ni/Fe₃O₄@MMSHS as a nanocatalyst. ^aReaction conditions: 1 mmol of aromatic amine, 1 mmol of sodium azide, 1.2 mmol of triethyl orthoformate, and 6 mg of Co-Ni/Fe₃O₄@MMSHS as a catalyst under solvent-free conditions at 80 °C. ^bIsolated yield.

From: Cobalt–nickel supported on magnetic mesoporous silica hollow spheres for efficient synthesis of tetrazole derivatives under solvent-free conditions