Synthesis and characterization of magnetic Fe3O4@Creatinine@Zr nanoparticles as novel catalyst for the synthesis of 5-substituted 1H-tetrazoles in water and the selective oxidation of sulfides with classical and ultrasonic methods

Abstract

Tetrazoles and sulfoxide compounds have a wide range of applications in industries and are of great expectation to be environmentally friendly and cost-effective. This paper reports the introduction of zirconium supported on Fe3O4 nanoparticles through creatinine post-functionalization modification of Fe3O4 (Fe3O4@Creatinine@Zr). The Fe3O4@Creatinine@Zr was characterized by a vibrating sample magnetometer, X-ray powder diffractometry, Fourier transforms infrared, scanning electron microscope, energy dispersive X-Ray analysis, thermogravimetric analysis, and inductively coupled plasma. Fourier transform-infrared spectroscopy results confirmed that creatinine was successfully immobilized on the surface of Fe3O4Cl with the presence of ν (C = N), and ν (C = O) bands of creatinine. X-ray diffraction data confirmed that the crystalline phase of Fe3O4 was not destroyed after modification. Vibrating sample magnetometer analysis showed that the saturation magnetization of the Fe3O4@Creatinine@Zr was 28.6 emu/g. The SEM-EDX results revealed that the zirconium complex was successfully incorporated into the structure of Fe3O4.This catalyst displayed high catalytic performance in the synthesis of 5-substituted 1H-tetrazoles and the selective oxidation of sulfides with classical and ultrasonic methods. The catalyst conferred strong Lewis's acidity sites for the activity and selectivity of the reactions. The obtained results showed that the fast oxidation of sulfides was happened by 0.2 mmol g −1 of zirconium that immobilized on the Fe3O4 nanoparticle at optimum condition (Sulfide (1 mmol), H2O2 (0.6 mL), ethanol (3 mL) and catalyst (Fe3O4@Creatinine@Zr, 60 mg) at room temperature.) The results showed that ultrasonic was an appropriate method for the oxidation of sulfides to the related sulfoxide at the optimum condition. The 5-substituted 1H-tetrazoles were afforded at optimum condition (Nitrile (1 mmol), NaN3 (1.2 mmol), H2O (3 mL), catalyst (100 mg) at 90 °C). The catalyst was separated by simple recovery and reused for seven periods without any remarkable decrease in the catalysis activity and selectivity. The output of this research can open a window for the synthesis the other organic materials under mild condition.