Synthesis of Imidazolium‐Based Ionic Liquid on Modified Magnetic Nanoparticles for Application in One‐Pot Synthesis of Trisubstituted Imidazoles
Reza Khalifeh, Vafa Naseri, Maryam Rajabzadeh
Abstract
Abstract The core‐shell of Fe 3 O 4 @SiO 2 modified by epichlorohydrin and 1‐methyl‐imidazole (Fe 3 O 4 @SiO 2 ‐EPIM), a new green recyclable nanocatalyst, was designed and prepared. This nanocatalyst was characterized using fourier‐transform infrared spectroscopy (FT‐IR), field‐emission scanning electron microscopy (FESEM), energy‐dispersive X‐ray spectroscopy (EDS), elemental mapping technique, transmission electron microscopy (TEM), X‐ray diffraction (XRD) techniques, thermal gravimetric analysis (TGA), N 2 adsorption‐desorption by Brunauer‐Emmet‐Teller (BET) and vibrating sample magnetometer (VSM). The catalytic activity of Fe 3 O 4 @SiO 2 ‐EPIM was assessed for synthesis of trisubstituted imidazoles via one‐pot condensation reactions of benzil, aldehyde and ammonium acetate under the optimal reaction condition (PEG 200, 100 °C, 0.02 g catalyst). This nanocatalyst displayed remarkable superiorities, such as environmental friendliness, shorter reaction time, excellent yields, reusability of the catalyst and simple workup procedure.