One-pot synthesis of tetrahydrobenzo[b]pyran derivatives through three-component condensation using Ni0.5Zn0.5Fe2O4 magnetic nanoparticles as reusable catalyst

Nowadays, magnetic nanoparticles (MNPs) as catalysts are interested of reserchers because of their advantages such as green, efficient, low-cost, magnetic properties and reusable catalysts [1]. One series of natural products that has structural unit are 4H-Pyrans. In the last decades, 4H-Benzo[b]pyrans have received considerable attention, that because of this attention due to their wide range activities such as anticoagulant, anticancer, anti-anaphylactic activities and diuretic [2-5]. Also this component can be employed as photoactive materials, pigments and utilized as potential biodegradable agrochemicals [6]. In the present study, we have reported green synthesis of Ni0.5Zn0.5Fe2O4 MNPs using that was carried out by the sol–gel method in arabic gum as a biopolymeric template. The catalyst was characterized by Fourier transform infrared spectrophotometer (FTIR), vibrating sample magnetometer (VSM), X-ray powder diffraction (XRD), scanning electron microscopy (SEM). The X-ray powder diffraction analysis revealed the formation of cubic phase ferrite MNPs with average particle size of 31 nm. The catalytic activity of Ni0.5Zn0.5Fe2O4 MNPs has been evaluated for the synthesis of tetrahydrobenzo[b]pyran derivatives through three-component under conditions Microwave irradiation and solvent free. Products were elucidated by 1HNMR and 13CNMR spectroscopy. Simple work-up, short reaction times, mild reaction conditions and excellent product yields (83–97%) are the advantageous features of this method.