A green and convenient method for the synthesis of 2-amino-3-phenylsulphonyl-4H-chromenes by a one-pot three-component condensation of 1-naphthol, phenylsulphonylacetonitrile and aromatic aldehydes under solvent-free conditions using potassium phosphate tribasic trihydrate as an efficient catalyst is described. The reaction of 1-naphthol with phenylsulphonylacetonitrile and various aromatic...

An efficient synthesis of chromenylphenylpropanone derivatives as warfarine-like analogues was developed by the Michael addition of 4-hydroxycoumarin to α,β-unsaturated compounds in the presence of polyvinylpolypyrrolidone supported antimony(III) chloride (PVPP-SbCl3) as a new polymeric Lewis acid catalyst in chloroform at reflux conditions without formation of 2,4-...

This study reports a new methodology for the efficient synthesis of trisphenol compounds using the reaction of 2,6-bis(hydroxymethyl) phenols with phenols under heterogeneous conditions. A sulfonated reduced graphene oxide (RGO-SO3H) nanocatalyst was used to promote the reaction under solvent-free conditions. A range of trisphenol compounds were produced in the presence of this c...

Fenton oxidation, an advanced oxidation process, is an efficient method for the treatment of recalcitrant wastewaters. Unfortunately, it utilizes H2O2 and iron-based homogeneous catalysts, which lead to the formation of high volumes of sludge and secondary pollutants. To overcome these problems, an alternate option is the usage of heterogeneous catalyst. In this study, a heterogeneous catalyst ...

The photocatalytic activity of Mn doped TiO2 for the ozonation of tetradifon pesticide in aqueous solution was studied. Various loadings of catalysts Mn/TiO2 (1%, 2.5% and 5%) was prepared and characterized by standard analytical techniques. Photocatalyzed ozonation with 2.5% Mn/TiO2 yielded 100% degradation and mineralization of tetradifon in 2.0 h under basic pH conditions. The extent of degr...

We designed a ceria-vanadia/silica (Ce-V/SiO2) heterogeneous catalyst and used it for the green and efficient synthesis of 2-amino-3-cyano-4H-pyran derivatives. The green reaction was a multicomponent one-pot condensation of 5,5-dimethylcyclohexane-1,3-dione, aromatic aldehyde, and malononitrile in an eco-compatible solvent (ethanol). The catalyst was synthesized and fully characterized by powd...

We decorated HS-functionalized cellulose nanocrystallite (CNC) films with monodisperse Au nanoparticles (AuNPs) to form a novel nanocomposite catalyst AuNPs@HS-CNC. The uniform, fine AuNPs were made by the reduction of HAuCl4 solution with thiol (HS-) group-functionalized CNC films. The AuNPs@HS-CNC nanocomposites were examined by X-ray photoelectron spectroscopy (XPS), TEM, ATR-IR and solid-st...

The catalytic purification of automobile exhaust gases (CO, NOx and hydrocarbons) is one of the most practiced conversion processes used to lower the emissions and to reduce the air pollution. Nevertheless, the good performance of exhaust gas purification catalysts often requires the high consumption of noble metals such as platinum. Here we report that the Brønsted acid sites on the external s...

Nanoporous metallic glass Pd, which was fabricated by dealloying of a glassy metallic alloy Pd(30)Ni(50)P(20), exhibited a remarkable catalytic activity for the Suzuki-coupling reaction between iodoarenes and arylboronic acids under mild conditions. Moreover, the catalyst can be reused several times without a significant loss of catalytic activity.