Gallium Oxide (Ga2O3): An Efficient Heterogeneous Nanocatalyst for One Pot, Multi-Component Synthesis of Polyhydroquinolines

A novel, facial, highly effective gallium oxide (Ga2O3) nanocatalyst was synthesized and characterized by FT-IR, X-ray diffraction pattern (XRD), Scanning electron microscope (SEM), and Energy-dispersive X-ray spectroscopy (EDAX) analysis. The resulting gallium oxide (Ga2O3) nanomaterial has been successfully used as a catalyst for condensation of various aldehydes, dimedone, ammonium acetate, and ethyl acetoacetate under ethanol condition to yield polyhydroquinoline derivatives via a one-pot four-component Hantzsch condensation reaction. The products were investigated by IR, NMR, and mass spectral techniques. The desired catalyst was recycled and reused without any considerable changes in the yield.

本研究合成了一种新型、简便高效的氧化镓（Ga₂O₃）纳米催化剂，并通过傅里叶变换红外光谱（FT-IR）、X射线衍射（XRD）、扫描电子显微镜（SEM）与能量色散X射线光谱（EDAX）对其完成了表征分析。所得氧化镓（Ga₂O₃）纳米材料已成功作为催化剂，在乙醇体系中催化各类醛、达米酮、乙酸铵及乙酰乙酸乙酯发生缩合反应，通过一锅四组分汉奇（Hantzsch）缩合反应生成多氢喹啉类衍生物。采用红外光谱、核磁共振波谱及质谱技术对所得产物进行了表征。该目标催化剂可回收复用，其催化活性未出现显著衰减，产物收率无明显变化。