An efficient method for the synthesis of 1,2,4,5-tetra substituted imidazoles usingK7Na3P2W18Cu4O68as catalyst is reported. This four-component condensation of benzil, aldehydes, amines, and ammonium acetate proceeds under solvent-free conditions. The catalyst is handling and recoverable.
AbstractSymmetrical and unsymmetrical 3,3-di(aryl)indolin-2-ones have been synthesized by nano-SiO2 as green, heterogeneous, and reusable catalyst under solvent-free conditions at room temperature via magnetic stirring and grinding methods. A plausible mechanism of condensation has also been presented.
An efficient and environmentally benign protocol for the one-pot, three-component synthesis of 12-aryl-8,9,10,12-tetrahydro-benzo[a]xanthen-11-one derivatives by condensation of aryl aldehydes, 2-naphthol and dimedone using H4SiW12O40(SiWA) as a reusable catalyst with high catalytic activity was reported. The reaction was carried out at 100 ºC under solvent-free conditions within 15-40 min in 82-91% yield.
Melamine trisulfonic acid was used as an efficient and recyclable catalyst for the one-pot synthesis of 10-aryl-6,8-dimethyl-6,10-dihydro-5-oxa-6,8-diazaanthra[2,3-d][1,3]dioxole-7,9-diones by condensation of 3,4-methylene dioxyphenol, aromatic aldehydes and 1,3-dimethylbarbituric acid under solvent-free conditions. Different types of aromatic. aldehydes were used in the reaction and in all cases the products were obtained in good to excellent yields.
Ionic liquid [DMEA][HSO4] was found to be an efficient and reusable catalyst for the one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes under solvent-free conditions. The excellent catalytic performances are believed to come from the synergetic effect of the cation and anion of the ionic liquid.
K7Na3P2W18Cu4O68: A Mild, Efficient, and Reusable Catalyst for the One-Pot Synthesis of 1,2,4,5-Tetra Substituted Imidazoles