Green synthesis and characterization of trisubstituted imidazole derivatives by an ecofriendly and efficient heterogenous nanocatalyst based on magnetite nanoparticles coated modified nanocellulose.

• A new magnetic nanoparticles of magnetite functionalized Schiff base modified nanocellulose [(pH-PDA-DANC)@Fe 3 O 4 NPs] was synthesized by an ecofriendly and a simple protocol. • The synthesized product was characterized using FTIR, XRD, SEM-EDX, and TGA analysis. • The magnetic nano-catalyst [(pH-PDA-DANC)@Fe 3 O 4 NPs] was used subsequently as a catalyst in the green and efficient procedure for one-pot multicomponent syntheses of imidazole derivatives. In the present work, a nanocellulose based magnetic nanocomposite [(pH-PDA-DANC)@Fe 3 O 4 NPs] was synthesized by an ecofriendly and a simple protocol and characterized by means of different techniques such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Thermal Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) equipped with an Energy Dispersive X-ray (EDX) probe and the Value Stream Mapping (VSM). The theoretical study of [(pH-PDA-DANC)@Fe 3 O 4 NPs] was investigated using Density Functional Theory (DFT) at the DFT-D3/ B3LYP/LanL2DZ level of theory to explore the nature of the interactions between the (pH-PDA-DANC) ligand and magnetite nanoparticles. The results indicate that the Fe 3 O 4 nanoparticles form covalent bonds with the N-ring of the ligand. Then, it was used as a catalyst in the green and efficient procedure for one-pot multicomponent syntheses of imidazole derivatives by the condensation of benzil or 9.10-phenanthrenequinone, benzaldehyde derivatives and ammonium acetate. The catalytic reaction provided the synthesis of above imidazole derivatives with high reaction efficiency (80 %-98.1 %) in a short reaction time (3 h) and in presence of a minimum amount of ethanol. The identification and structure of imidazole derivatives was determined analyzing the 1H NMR (Nuclear Magnetic Resonance) and FTIR spectra. This procedure has several advantages compared to the conventional method such as the high yields, short reaction times, easy separation of the nanocatayst from the reaction mixture by using a magnet, and the reusability of the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]