A new copper Schiff‐base complex of 3,4‐diaminobenzophenone stabilized on magnetic MCM‐41 as a homoselective and reusable catalyst in the synthesis of tetrazoles and pyranopyrazoles
Tavan Kikhavani, Parisa Moradi, Mohammad Mashari‐Karir, J. Naji
Abstract
This work discusses the synthesis and characterization of new copper Schiff‐base complex of 3,4‐diaminobenzophenone stabilized on magnetic MCM‐41 as a magnetically reusable catalyst. At first, Fe 3 O 4 magnetic nanoparticles were synthesized via a chemical co‐precipitation method using FeCl 2 .6H 2 O and FeCl 3 .6H 2 O in basic solution of ammonia. Then magnetic MCM‐41 were synthesized via Fe 3 O 4 ‐doped into mesoporous channels of MCM‐41. Further a new copper Schiff‐base complex of 3,4‐diaminobenzophenone was supported on magnetic MCM‐41 and was used as a practical and magnetically reusable catalyst in organic reactions such as homoselective synthesis of tetrazole and pyranopyrazole derivatives. This catalyst was characterized by several techniques such as scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDS), wavelength dispersive X‐ray spectroscopy (WDX), thermogravimetric analysis (TGA), X‐ray powder diffraction (XRD), atomic absorption spectroscopy (AAS), Fourier transform‐infrared spectroscopy (FT‐IR), Brunauer–Emmett–Teller (BET), and vibrating sample magnetomter (VSM). This catalyst display good selectivity, high activity, stability and facile magnetic separation. Therefore, this catalyst can be recycled for several times without significant loss of its catalytic efficiency.