Immobilization of nickel on Kryptofix 222 modified Fe₃O₄@PEG core‐shell nanosphere for the clean synthesis of 2‐Aryl‐2,3‐dihydroquinazolin‐4(1H)‐ones

Abstract

The development of green‐based nanostructures is extremely compelling for their implementation in the catalytic arena. In this study, a new type of magnetically core‐shell nanocomposite was successfully designed to be used as a green catalyst for the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐ones under ultrasonic irradiation. Initially, magnetic Fe3O4 nanoparticle (NP) cores were fabricated via the co‐operation method and subsequently coated with polyethylene glycol (PEG). After that, the macro‐bicyclic Kryptofix 222 (KP222) functionalized on the surface of Fe3O4@PEG for graft and stabilization of nickel metal. The obtained Ni@KP222/Fe3O4@PEG nanocomposite was characterized by FT‐IR (Fourier Transform Infrared), wide‐angle XRD (X‐ray Powder Difraction), FESEM (Field Emiossion Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), VSM (Vibrating‐Sample Magnetometer), TGA‐DTA (Thermogravimetrtic Analysis‐ Differential Thermal Analysis), DLS (Dynamic Light Scattering), and BET (Brunauer–Emmett–Teller) spectroscopy and technique. The findings indicated that high‐affinity KP222 ligand in the stabilization of Ni2+ and ultrasound irradiation catalyzed synergistically the formation of the 2,3‐dihydroquinazolin‐4(1H)‐ones. The benzaldehydes with electron‐withdrawing and electron donor groups could react well with the amino benzamide under ultrasound irradiation in 5 min, indicating that the reaction was not sensitive to the electronic effects. Furthermore, the reusability test for the Ni@KP222/Fe3O4@PEG catalyst revealed successful recyclability for six runs. The current study provided a rational design and synthesis of multifunctional catalysts for catalytic applications.