A simple, green and efficient method for synthesis of 2,4,5-trisubstituted imidazoles is described via three-component cyclocondensation of benzil or benzoin, aldehyde and ammonium acetate by using the nano SiO2-supported ferric hydrogen sulfate (FHS/SiO2), as a catalyst, under solvent-free conditions. The nano SiO2 support and catalyst were characterized by X-ray diffraction (XRD), transmissio...

background: enzymes are well known as sensitive catalysts in the laboratory and industrial scale. to improve their properties and for using their significant potential in various reactions as a useful catalyst the stability of enzymes can often require improvement. enzymes immobilization on solid supports such as epoxy- functionalized ferric silica nanocomposite can be effective way to improve ...

a green and convenient method for the synthesis of 14-aryl-14h-dibenzo[a,i]xanthene-8,13-diones and spiro[dibenzo[a,i]-xanthene-14,3'-indoline]-2',8,13-triones in the presence of a catalytic amount of cellulose sulfuric acid (csa) as an efficient biopolymer-based catalyst under solvent-free conditions at 100 °c is described. the condensation reactions of β-naphtol, 2-hydroxynaphthalene-1,4-dion...

an efficient, simple and convenient route is described for the synthesis of biscoumarin (3,3'-(arylmethylene) bis (4-hydroxy-2h-chromen-2-one)) by using of recyclable catalyst tio2@ksf. in this method, we synthesis biscoumarin derivatives via 3multi-component reactions (3mcrs) of two equivalent 4-hydroxycoumarin with one equivalent of aromatic aldehydes using 20 mg nano tio2@ksf as homogen...

An efficient, simple and convenient route is described for the synthesis of biscoumarin (3,3'-(arylmethylene) bis (4-hydroxy-2H-chromen-2-one)) by using of recyclable catalyst TiO2@KSF. In this Method, we synthesis biscoumarin derivatives via 3multi-component reactions (3MCRs) of two equivalent 4-hydroxycoumarin with one equivalent of aromatic aldehydes using 20 mg nano TiO2@KSF as homogeneous ...

Graphene films were fabricated over synthesized MCM-41 nanocatalyst by chemical vapordeposition method, and the reaction was carried in atmospheric pressure at 750˚C. Acetylenegas used as a carbon precursor and the synthesis reaction took place in hydrogen atmosphere.Mesoporous MCM-41 was synthesized at room temperature, using wet chemical method. Thesynthesized metal free catalyst was characte...

A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally fri...

a simple, green synthesis of n-alkyl-3-acetyl-2-methylpyrrole derivatives using zno nanoparticles from the three component reaction of aliphatic amines, acetylacetone (as a 1,3-dicarbonyl compound) and α-haloketones under solvent-free condition is described.

A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally fri...