Green and efficiently synthesized tetrasubstituted imidazole: introduced bismuth oxide co-doped Lu 3+ , Er 3+ as a novel reusable heterogeneous nanocatalyst

Nano-structured Bi1.5(Lu, Er)0.5O3 was synthesized efficiently and utilized as a novel environmentally benign and recyclable heterogeneous catalyst for the synthesis of tetrasubstituted imidazole derivatives in water under ultrasonic irradiation. This synthesis method offers the several advantages such as green and eco-friendly protocol, operational simplicity, mild reaction conditions, short reaction time, higher yields, and easy work-up procedures. For this purpose, nano-structured bismuth oxide and Lu3+, Er3+ co-doped Bi2O3 with different Lu3+, Er3+ loadings (0.1, 0.5%mol) were synthesized by a simple hydrothermal method. The obtained catalysts were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscope, Fourier-transform infrared spectroscopy, and UV–Vis absorption spectroscopy. X-ray analyses of obtained bismuth oxide were indexed as monoclinic phase and nano co-doped bismuth oxides (Bi2 – x (Lu, Er)xO3, x = 0.1, 0.5%mol) have tetragonal phase.