nano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents.  this nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. the prepared sulfated titania s...

A novel, efficient and one-pot method for preparation of 1, 8-dioxo-octahydroxanthene derivatives is reported using Nafion-H as an effective heterogeneous catalyst under thermal and solvent-free conditions. This method has the advantages of high yields, a cleaner reaction, simple methodology, easy work-up and greener conditions. The catalyst is easily prepared, stable, reusable and efficient un...

A green and efficient one pot, three component protocol for synthesis of naphthopyranopyrimidines by cyclocondensation of β-naphthol, aldehyde, and 6-amino-1,3-dimethyluracil using L-proline as a beneficial catalyst with high catalytic activity under solvent-free conditions at 100 °C is described. In this study, several types of aromatic aldehyde, containing electron-withdrawing groups as well ...

The reaction of 2-naphthol and also para-substituted phenols with glyoxal in presence of choline chloride: 2 ZnCl2 [ChCl: 2ZnCl2], a deep eutectic solvent (DES), as a green catalyst was studied. The amount of catalyst, solvent type, temperature, and time on the yield of reaction were investigated. It was found that the optimal condition included 10% mol ratio of catalyst (mol percentage of DES ...

ni2+ supported on hydroxyapatite-core@shell γ-fe2o3 nanoparticles (γ-fe2o3@hap-ni2+) was found to be a useful catalyst for the synthesis of benzimidazole derivatives from o-phenylenediamine and aldehydes under solvent and solvent-free conditions at 80 °c. this reaction affords the corresponding benzimidazole derivatives compared with the classical reactions this method consistently gives a high...

in this work, the efficiency, generality and applicability of new bronsted acidic ionic liquid (bail) 1-methyl-3-(2-(sulfooxy)ethyl)-1h-imidazol-3-ium chloride {[msei]cl} as heterogeneous and green catalyst for organic transformations are studied. herein, the following one-pot multi-component reactions in the presence of [msei]cl are investigated: (i) the synthesis of quinoxaline derivatives fr...

Kinetic study of free fatty acids (FFAs) esterification for biodiesel production from palm fatty acid distillate (PFAD) using sulfated zirconia (S-ZrO2) prepared by solvent-free method calcined at low temperature as the heterogeneous catalyst was studied. The reaction was performed in a batch-stirred reactor at the different temperature to obtain the kinetic data. The effect of reaction conditi...

This study introduces a green and efficient method for preparation of biologically-active substituted 4H-pyrans using the one-pot three-component reaction of aromatic aldehydes, dimedone and malononitrile in the presence of cobalt oxide nanoparticles. Co3O4 nanoparticles were used as an efficient catalyst for the synthesis of polyhydroquinoline derivatives by the reaction ...

this study offers an exclusive class of magnetic nanoparticles supported hyperbranched polyglycerol (mnp/hpg) that was functionalized with citric acid (mnp/hpg-ca) as a host immobilization of palladium nanoparticles. the mnp/hpg-ca/pd catalyst was fully characterized using some different techniques such as thermogravimetric analysis (tga), x-ray diffraction (xrd), transmission electron microsco...

This study introduces a green and efficient method for preparation of biologically-active substituted 4H-pyrans using the one-pot three-component reaction of aromatic aldehydes, dimedone and malononitrile in the presence of cobalt oxide nanoparticles. Co3O4 nanoparticles were used as an efficient catalyst for the synthesis of polyhydroquinoline derivatives by the reaction ...