Novel One-Pot Synthesis of Pyrazolopyranopyrimidinones Using Newly Produced γ-Alumina Nanoparticles as Powerful Catalyst

g-Alumina nanoparticles (g-Al2O3 NPs) were prepared via a new and simple synthetic route and characterized by field emission scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The catalytic activity of prepared g-Al2O3 NPs was investigated for the new one-pot, four-component synthesis of some fused tri-heterocyclic compounds containing pyrazole, pyran, and pyrimidine. In another investigation, the recyclability of the prepared nanocatalyst was also studied. It was proved that the nanoparticles can act effectively for at least four cycles without appreciable loss in activity. This novel procedure has some advantages such as high efficiency, simplicity, high rate, and environmental safety.