exploration of catalytic performance of nano-la2o3 as an efficient catalyst for dihydropyrimidinone/thione synthesis and gas sensing

In the present work, we report an proficient, elegant, and rapid one-pot synthesis of variety of 3,4-dihydropyrimidine-2(1h)-one/thione derivatives from β-dicarbonyl compounds, urea/thiourea, and various aromatic aldehydes using nano-la2o3 catalyst under ultrasonic irradiation. this novel synthetic strategy benefits with excellent yields, short reaction time, benign reaction conditions, clean transformation, and purification of products by non-chromatographic strategies. in addition, the synthesized nano-material was also explored as an effective gas sensor for no2, lpg, methyl alcohol, and ammonia. the gas-sensing properties such as selectivity and sensitivity of selected gases along with response and recovery for nano-la2o3 sensor are reported in this paper. in this way, conferring nano-la2o3 is a multifunctional catalyst not only for organic synthesis but also for gas sensing. the synthesized la2o3 nano-material was characterized by fourier transform ir, powder x-ray diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive spectroscopy, and brunauer–emmett–teller isotherm. the formation of biginelli adducts was confirmed by fourier transform ir, 1hnmr, 13cnmr, dept-135 (distortionless enhancement by polarization transfer spectra), and mass spectral techniques.