An effective and eco‐friendly sonochemical multicomponent synthesis of trisubstituted imidazoles via modified silica‐coated cobalt ferrite nanoparticles by tungstic acid

Abstract

This research is providing a method for the synthesis of 2,4,5‐trisubstituted imidazole derivatives based on pursuing the green chemistry principles. Therefore, a one‐pot multicomponent cyclocondensation reaction through aldehyde interaction with ammonium acetate and 1,2‐diketone was carried out in EtOH:H2O solvent under ultrasound irradiation. This protocol was utilized as an eco‐effective synthetic route by applying CoFe2O4@SiO2@(‐CH2)3OWO3H nanocomposite as a nanocatalyst. The stabilized tungstic acid on 3‐chloropropyl anchored to SiO2‐coated CoFe2O4 magnetic nanoparticles was designed, prepared, and applied as a recyclable heterogeneous acid catalyst to attain high product yields and short reaction times. The structure of nanocatalyst was confirmed by using Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), energy dispersive spectroscopy (EDS), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) techniques, and the obtained organic derivatives were examined through melting point, FT‐IR, and 1H NMR analyses.