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The Acid Modification of Bentonite clay (AMC) process was firstly reported and has been developed in one pot by ionic exchange of inorganic interlayer clay combined with different concentrations of acid (H2SO4) under Microwave irradiation. The maximum basal spacing of 28 Å was found in 2 M AMC clay confirmed PXRD analysis. EDAX micrographs of raw and AMCs showed the percentage of elemental analysis (H% = 38.21 for 2 M). Further, it was successfully applied in the Biginelli reaction of Dihydropyrimidinones (DHPMs) synthesis by cyclocon densation reaction under microwave irradiation and structurally confirmed by spectral techniques such as HNMR, C13NMR, FT-IR, Mass and UV-Visible absorption spectra. The yields of DHPMs are 88%, 90%, 92% and 92.6% for EMDHPM, EMNDHPM, EMMDHPM and EMHMDHPM respectively. The antimicrobial activity of synthesized dihydropyrimidinones was examined using Gram-positive (Staphylococcus aureus) and Gram-negative (E. coli) bacterial species showed efficiently inhibited the bacterial growth activities at 4 mg/mL concentration. The results confirmed that the newly prepared DHPMs compounds act as efficient antimicrobial agent and synthesized AMC material as potential catalyst.

The solid acids such as ZrO2, Al2O3 and ZrO2-Al2O3 containing different ZrO2 loadings (10–80 mol%) were prepared by solution combustion method (SCM) and characterized for their total surface acidity by NH3-TPD/n-butylamine back titration method and crystallinity by powder X-ray diffraction (PXRD) technique. These solid acids were evaluated for their catalytic activity in the synthesis of novel O-acetylated products from substituted phenols, pyridine alcohols and aryl alcohols with acetic anhydride (AA) as an acetylating agent. The reaction conditions were optimized by varying the catalyst, molar ratio of the reactants, reaction temperature and amount of the catalyst. All the solid acids used in this study exhibited good catalytic activity in the reaction. In particular, ZrO2-Al2O3 containing 80 mol% of ZrO2 was found to be highly active in the acetylation reaction with high yield of acetylated products. Triangular correlation between the surface acidity, crystallinity and catalytic activity of solid acids was observed. These solid acids were found to be reactivable and reusable. Keywords: ZrO2-Al2O3, Solid acid, Solution combustion, Novel acetylated compounds, O-acetylation