This paper describes the applicability of 1,3-dichloro-5,5-dimethylhydantoin, as a cheap, stable and commercially available catalyst, in the promotion of the synthesis of 1,8-dioxo-octahydro-xanthenes (DOXOs) via the one-pot condensation of aldehydes and cyclic 1,3-dicarbonyl compounds. This novel synthetic method has the advantages of high yields, short reaction times, low cost and av...

The direct three component modified Mannich reaction via condensation of aldehydes, 2-naphthol or 2,7-naphthalendiol and piperidine to generate Betti bases has been carried out over L-proline (20 mol%) with high efficiency under solvent free conditions at 70 OC. Also, the reaction of aromatic aldehyde and 4-hydroxycoumarin in the presence of L-proline (20 mol%) in the ethanol under reflux condi...

A highly efficient and environmentally friendly synthesis of various 1,5-diaryl-3-(arylamino)-1H-pyrrol-2(5H)-ones catalyzed by 1-methylpiperidinium hydrogen sulfate via one-pot cyclo-condensation reaction ofaldehydes, amines and ethyl 2-oxopropanoate under ambient conditions has been explored. The presentmethodology offers several advantages such as good yields, simple procedure, shorter react...

the condensation of benzylamine with glyoxal leads to hexabenzylhexaazaisowurtzitane (hbiw) in acetonitrile solvent with citric acid as a green catalyst under both conventional stirring and ultrasonic irradiation conditions. the influence of four variables, including the amount of catalyst, solvent, reaction time and ultrasonic power, on the reaction yield was investigated. the results showed t...

TiCl4/nano-cellulose as a biodegradable and eco-friendly Lewis acid catalyst was synthesized via reaction of nano-cellulose and TiCl4. This catalyst was characterized and used for synthesis of asymmetric highly functionalized tetrahydropyridines via a five-component condensation reaction of p-substituted anilines, aldehydes and ethyl acetoacetate under solvent-free condition. Simple methodology...

A simple and environmentally benign procedure for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes by a one-pot condensation of 2-naphthol with aromatic aldehyde in the presence of [Et3NH][HSO4] as an acidic ionic liquid catalyst under solvent-free conditions has been developed. The reaction work-up is very simple and the catalyst can be easily separated from the reaction mixture and reused s...

Iso-butyric acid as a new, simple, and expensive solvent/catalyst was successfully used for the chemoselective Fischer’s synthesis of indolenines derivatives 3a-r by one-pot condensation reaction of various phenylhydrazines 1a-e with the substituted acetophenones 2a-c at reflux conditions. In this protocol, all products 3a-r were obtained in high yields and short reaction time. The structures o...

The reaction of methyl ketones 1a-g with dimethylformamide dimethylacetal (DMFDMA) afforded the enaminones 2a-g, which were coupled with diazotized aromatic amines 3a,b to give the corresponding aryl hydrazones 6a-h. Condensation of compounds 6a-h with some aromatic heterocyclic amines afforded iminoarylhydrazones 9a-m. Enaminoazo compounds 12a,b could be obtained from condensation of 6c with s...

a highly efficient, simple and clean solvent-free protocol for the synthesis of polyhydroquinolines is described. the one-pot multi-component condensation reaction between arylaldehydes, dimedone (5,5-dimethylcyclohexane-1,3-dione), β-ketoesters and ammonium acetate in the presence of catalytic amount of (2.5 mol%) melamine trisulfonic acid (mtsa) as a recyclable, green and attractive sulfonic ...