Various types of aldehydes undergo crossed-Aldol condensation with ketones in the presence of melamine trisulfonic acid (MTSA) under solvent-free conditions. The reported method is mild, efficient and has the advantages such as using heterogeneous catalysis, short reaction times, high yields of the products and the recyclability of the catalyst.

two-component reaction of 2-aminobenzophenones with acetylenic esters in the presence of γ-al2o3 and cu/zno as suitable heterogeneous catalysts has been studied. nano γ-al2o3 and cu/zno showed high activities when used as surface catalysts for the synthesis of quinoline derivatives. after completion of the reaction, the catalyst was recovered and reused several times under the same reaction con...

in this work, so3h-functionalizedphthalimide (sfp) as a so3h-containing solid acid is prepared by the reaction of phthalimide with chlorosulfonic acid, and characterized by ft-ir, 1h and 13c nmr, mass, tg, dtg, xrd and sem. then, it is utilized as a highly efficient, heterogeneous and green catalyst for the one-pot multi-component condensation of dimedone with arylaldehydes, β-ketoesters and am...

sulfonated polystyrene/montmorillonite nanocomposite (ommt/ps-so3h) was prepared and used as a novel, efficient and inexpensive heterogeneous acid catalyst in the one-pot reaction three-component mannich reaction of ketones, aromatic aldehydes and amines under solvent-free conditions. the catalyst was characterized by xrd, sem, tg, bet and ft-ir techniques. this method has advantages of high yi...

an efficient synthesis of polyhydroquinoline derivatives was reported via four-component coupling reactions of aldehydes, 1,3-dicarbonyl ketones (dimedone or 1,3-cyclohexanedione), ethyl acetoacetate or methyl acetoacetate and ammonium acetate in the presence of a catalytic amount of nanocrystalline tio2 under solvent free conditions. the reported method is mild, rapid and has the advantages su...

a mild, efficient and fast method for the oxidation of alcohols and trimethylsilyl, tetrahydropyranyl and methoxymethyl ethers to their corresponding carbonyl compounds using cro3 in the presence of rice husk ash (rha) is reported. all reactions were performed at room temperature in high to excellent yields. a new, efficient and green catalyst, heterogeneous reaction conditions, easy work-up of...

a mild, efficient and fast method for the oxidation of alcohols and trimethylsilyl and tetrahydropyranyl ethers to their corresponding carbonyl compounds using cro3 in the presence of sulfonic acid functionalized ordered nanoporous na+-montmorillonite (sanm) and under solvent-free conditions is reported. all reactions were performed at room temperature in high to excellent yields. ease of the p...

A mild, efficient and fast method for the oxidation of alcohols and trimethylsilyl and tetrahydropyranyl ethers to their corresponding carbonyl compounds using CrO3 in the presence of sulfonic acid functionalized ordered nanoporous Na+-montmorillonite (SANM) and under solvent-free conditions is reported. All reactions were performed at room temperature in high to excellent...

In this study, the nano-SiO2/hexamethylenetetramine as a new basic heterogeneous nanocatalyst was prepared and used for the synthesis of pyranopyrazole via the four-component reaction. Various aldehydes, hydrazine hydrate, ethyl acetoacetate and malononitrile were reacted at room temperature under solvent-free and grinding conditions. The morphology and structure of nano-cat...