In this article, catalytic microwave synthesis of dihydropyrimidinones over zirconia-based solid acids coated on honeycomb monoliths is presented. Solid acids such as ZrO2, Mo(VI)/ZrO2, W(VI)/ZrO2 and Pt-SO42-/ZrO2 were coated on honeycomb monoliths and characterized for their physico-chemical properties such as surface acidity by NH3-Temperature programmed desorption (TPD), crystalinity by Powder X-ray diffraction (PXRD), functionality, by Fourier transform infrared spectroscopy (FTIR) and morphology by Scanning electron microscopy (SEM). The elemental composition was measured by using Inductively coupled plasma optical emission spectrometry (ICP-OES). These catalytic materials were subjected to catalytic activity by means of Biginelli reaction using benzaldehyde, ethylacetoacetate and urea to synthesize dihydropyrimidinones under microwave heating condition. The reaction conditions such as nature of catalytic material, temperature and time were optimized to obtain the highest possible yield of the desired product. A series of dihydropyrimidinone derivatives were synthesized under optimized reaction conditions by taking different substituted benzaldehydes. Reactivation and reusability of the honeycomb catalytic material was also studied.
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