Magnetically recoverable Fe 3 O 4 @SiO 2 @SBA-3@2-ATP-Cu: an improved catalyst for the synthesis of 5-substituted 1 H -tetrazoles.

Functionalization of Fe 3 O 4 @SiO 2 @SBA-3 with double-charged 3-chloropropyltrimethoxysilane (CPTMS) and 2-aminophenol, followed by mechanical mixing of the solid product with copper(i) chloride produces a new, greener and efficient Fe 3 O 4 @SiO 2 @SBA-3@2-ATP-Cu catalyst for the synthesis of 5-substituted 1 H -tetrazoles. XRD, SEM, atomic absorption, TGA, N 2 adsorption-desorption, and VSM analyses were performed for the characterization of the Fe 3 O 4 @SiO 2 @SBA-3@2-ATP-Cu structure. Nitrogen adsorption-desorption analysis revealed that Fe 3 O 4 @SiO 2 @SBA-3@2-ATP-Cu has a surface area of 242 m 2 g -1 and a total pore volume of 55.72 cm 3 g -1 . In synthesizing 5-substituted 1 H -tetrazoles, Fe 3 O 4 @SiO 2 @SBA-3@2-ATP-Cu shows superior yields in short reaction times at 120 °C. This catalyst also showed high thermal stability and recyclability at least for 4 runs without apparent loss of efficiency.