CdO nanoparticles efficiently catalyzes the condensation of aromatic aldehydes with 2-aminophenol at room temperature to afford 2-aryl benzoxazole derivatives by grinding method. The reactions proceed under heterogeneous and mild conditions to provide 2-aryl benzoxazoles in excellent yields (87-97 %) with high purity under solvent free condition. The reaction requires short time (5-23 minutes) ...

Silica Vanadic Acid, SVA, (oxo-vanadium has been supported on silica) as a dual Lewis and Bronsted acid ability was prepared and efficiently catalyzed one-pot multi-component condensation of enolizable ketones or alkyl acetoacetates with aromatic aldehydes, acetonitrile and acetyl chloride. The described reaction was produced β-acetamido ketone or ester derivatives in high to excellent yields i...

An environmentally benign procedure for the synthesis of vicinal nitrohydrins via the regioselective ring opening reaction of epoxides with nitrite anion using silica-bound 3-{2-[poly(ethylene glycol)]ethyl}-substituted 1-methyl-1H-imidazol-3-ium bromide as an effective heterogeneous phase transfer catalyst was described. Short reaction time, high yield of products, simple work-up proc...

A simple and mild one-pot three-component reaction for the preparation 1,4-dihydropyridines has been developed from various aldehyde substrates, 1,3-dicarbonyl compounds (dimedone) and ammonium acetate (Hantzsch method) in the presence of a catalytic amount of phospho sulfonic acid (PSA) as an efficient and heterogeneous solid acid in EtOH at room temperature. Preparation of PSA is straightforw...

a simple and mild one-pot three-component reaction for the preparation 1,4-dihydropyridines has been developed from various aldehyde substrates, 1,3-dicarbonyl compounds (dimedone) and ammonium acetate (hantzsch method) in the presence of a catalytic amount of phospho sulfonic acid (psa) as an efficient and heterogeneous solid acid in etoh at room temperature. preparation of psa is straightforw...

in this report, synthesis, characterization and application of silica perchloric acid nanosphere as a novel and heterogeneous catalyst is described. these nanospheres have been characterized by xrd, ft-ir, bet and tga spectra and also by sem and tem images. the results show that it has a spherical shape and the particles size are between 75 and 100 nm. the catalytic activity has been investigat...