an efficient and green method for the synthesis of pyrano[3,2-c]chromene or pyrano[4,3-b]pyrone derivatives is described by using a three-component condensation process of malononitrile, aldehyde, and 4-hydroxycoumarine or 4-hydroxypyrone in [bmim]bf4-licl as an ionic liquid.

in this work, a green, simple and highly efficient procedure for the synthesis of bis(indolyl)methanes is described. the condensation of indoles with carbonyl compounds catalyzed by citric acid in water affords bis(indolyl)methanes in high yields and relatively short reaction times. the advantages of this method are using of water as a low cost solvent and efficient recyclability of the catalyst.

Bio-directed synthesis of nanoparticles is an interesting field of rapid advancement for biologists,chemists and materials scientists, especially in light of efforts to find out green methods of inorganicmaterial synthesis. In the present study, green synthesis of platinum nanoparticles (PtNPs) using sheepmilk is reported for the first time. By adjusti...

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...

Abstract Green synthesized nanomaterials have garnered much attention due to their economic and ecofriendly benefits over common chemical methods of synthesis. In the present study, zinc oxide nanoparticles with an average diameter of 16.51 nm were successfully biosynthesized using the aqueous extract of the red seaweed Hypnea musciformis. The morphology, purity and quality of biosynthesiz...

1-Methyl-3-(2-oxyethyl)-1H-Imidazol-3-ium-Borate Sulfonic Acid ([MOEI]-BSA) was easily prepared and used as a new and highly efficient solid acid catalyst for the synthesis of benzimidazole derivatives with high isolated yields. Various substituted benzimidazoles were synthesized by a combination of o-phenylenediamines and aldehydes in the presence of [MOEI]-BSA with excellent yields in water a...

Nowadays green synthesis of metal nanoparticles is a developing area of research. In this study, titanium dioxide nanoparticles were biosynthesized using an aqueous solution of Echinacea purpurea herba extract as a bioreductant. This is novel and interesting method for synthesis of TiO2 nanoparticles. The prepared titanium dioxide nanoparticles were characterized using ultraviolet-visible spect...

a mild and efficient one-pot three-component and environmentally benign approach for the synthesis of a wide range of hydantoin annulated derivatives has been described. a multi-component reaction between a carbonyl compounds (ketone or aldehyde), potassium cyanide and ammonium carbonate (as cyanating agent and amine source, respectively leads to the formation of hydantoins. the proposed optimi...

In this research study, methanol synthesis catalysts were manufactured with various mole ratios of metal carbonates (zinc, copper and aluminum carbonate) and ammonium hydrogen carbonate via a green solid-state method that employed a ball mill apparatus. Some parameters for the catalyst preparation, such as Al mole percent, Cu/Zn mole ratio, rotations milling speeds and aging time, were optimize...

Catalysis by transition-metal nanoparticles has undergone an explosive growth during the past decade. This special issue presents the general trends in the current research in this field, the present situation concerning scope and limitations, as well as the future perspectives. Original contributions are also presented on the applications of nano-catalysts to the green synthesis.