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

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, Fe3O4 magnetic nanoparticles were synthesized via a chemical co‐precipitation method using FeCl2.6H2O and FeCl3.6H2O in basic solution of ammonia. Then magnetic MCM‐41 were synthesized via Fe3O4‐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.

Synthesis of tetrazoles catalyzed by a new and recoverable nanocatalyst of cobalt on modified boehmite NPs with 1,3-bis(pyridin-3-ylmethyl)thiourea

“…4 O-H and N-H bands appeared above 3000 cm −1 in the FT-IR spectra. 46 In addition, the stretching vibrations of Si-O identied in region 805 cm −1 and 1075 cm −1 of FT-IR spectra. 41,47 In addition, stretching vibrations of the C]N groups have appeared in the 1635 cm −1 region.…”

“…Based on reported authentic methodologies about synthesis of tetrazoles in the presence of immobilized transition metal catalysts, 46,54 a mechanism cycle for the synthesis of tetrazoles in the presence of Co-(PYT) 2 @BNPs catalyst offered in Scheme 4.…”

Novel neodymium complex on MCM‐41 magnetic nanocomposite as a practical, selective, and returnable nanocatalyst in the synthesis of tetrazoles with antifungal properties in agricultural

“…Unfortunately, Fe 3 O 4 magnetic nanoparticles have lower surface area and lower stability. [16][17][18][19][20] Therefore, a nanocomposite of both MCM-41 and Fe 3 O 4 magnetic nanoparticles is great interest for various applications, especially in the field of catalysis, because MCM-41 MNC has advantages of both mesoporous MCM-41 and Fe 3 O 4 magnetic nanoparticles. [4,21] Therefore, MCM-41 MNC, which is formed from magnetic core surrounding by a mesoporous shell, has been used in the preparation of magnetically recyclable nanocatalysts due to its unique properties such as stable in different chemical reaction conditions, high stability, high-specific surface area, and ability to modify its surface, insolubility, and recoverability.…”

Immobilization of Ni(ii) complex on the surface of mesoporous modified-KIT-6 as a new, reusable and highly efficient nanocatalyst for the synthesis of tetrazole and pyranopyrazole derivatives

“…For example, pyranopyrazole derivatives can be synthesized from the four-component condensation of hydrazine hydrate, ethyl acetoacetate, aldehyde derivatives, and malononitrile. 48–51 Significantly, pyranopyrazoles have been used as potential inhibitors of human CHK-1 kinase, and for their insecticidal, pharmaceutical, antimicrobial, anticancer, anti-inflammatory, antiviral, analgesic, and vasodilator activities. 41,52–58…”

“…For example, pyranopyrazole derivatives can be synthesized from the fourcomponent condensation of hydrazine hydrate, ethyl acetoacetate, aldehyde derivatives, and malononitrile. [48][49][50][51] Signicantly, pyranopyrazoles have been used as potential inhibitors of human CHK-1 kinase, and for their insecticidal, pharmaceutical, antimicrobial, anticancer, anti-inammatory, antiviral, analgesic, and vasodilator activities. 41,[52][53][54][55][56][57][58] In this sense, the aim of the present article is to design an effective and convenient method for the stabilization of a new complex of nickel with s-methyl isothiouronium sulfate on KIT-6 (KIT-6@SMTU@Ni) in the synthesis of tetrazoles and pyranopyrazoles.…”