A new Schiff-base-N-propylhydrazine-1-carbothioamide complex of copper on boehmite nanoparticles as a recoverable catalyst in the homoselective synthesis of 5-substituted tetrazoles

Abstract

In this work, 2-(2-hydroxybenzylidene)hydrazine-1-carbothioamide (Schiff-base-HBHCT) was synthesized, and it was identified by FT-IR, ¹H NMR, and ¹³C NMR spectroscopies. Besides, 3-iodopropyltrimethoxysilane (3-IPTMS) was synthesized by a simple S_N2 reaction of 3-chloropropyltrimethoxysilane and potassium iodide in dry acetone. Also, boehmite nanoparticles are synthesized by a simple route and available commercial materials. Then, the surface of boehmite nanoparticles was modified by 3-IPTMS, and then it was further functionalized by Schiff-base-HBHCT. Finally, the copper ion became complex with functionalized Schiff-base-HBHCT (Cu-Schiff-base-HBHCT@boehmite). The particle size and morphology of Cu-Schiff-base-HBHCT@boehmite were studied by SEM images. Organic moieties and elemental composition of Cu-Schiff-base-HBHCT@boehmite were investigated by TGA, AAS, EDS, and WDX analysis. The surface area of Cu-Schiff-base-HBHCT@boehmite was calculated by nitrogen adsorption/desorption analysis, including BJH and BET methods. In the final step, the catalytic application of Cu-Schiff-base-HBHCT@boehmite was studied in the homoselective synthesis of tetrazoles. This catalyst has shown good reusability in the synthesis of tetrazoles.