China's Security Protection of Chinese Nationals in the Middle East

The current study focuses on the green synthesis of 2,3-dihydroquinazolin-4-one (DHQZ), an important pharmaceutical compound, using water as a solvent and zeolite as a solid acid catalyst. This green protocol is acid catalysed and involves the condensation of 2-aminobenzamide with aldehydes over a recyclable mesozeolite H-BEA catalyst. The synthesised mesozeolite H-BEA catalyst is prepared using dodecyl trimethyl ammonium bromide (DTAB) as a cationic surfactant and yeast as an additional pore modifier. The synthesised catalyst (mesozeolite H-BEA) has been characterized by several characterization techniques specifically, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), solid-state magic angle spinning nuclear magnetic resonance (Al-27, Si-29, and H-1 MAS NMR), N-2 sorption isotherms analysis, ammonia-temperature programmed desorption (NH3-TPD) analysis, scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) and thermo-gravimetric (TG) analysis. The synthesized mesozeolite exhibited bimodal porosity having both meso and microporosity of zeolite BEA. The % Yield of DHQZ derivatives over synthesized mesozeolite BEA catalyst was found to be better as compared to its parent zeolite, which may be due to its improved physicochemical characteristics. In addition, two novel halogen-substituted derivatives of DHQZ are synthesized over a modified zeolite BEA catalyst.