this study introduces a green and efficient method for preparation of biologically-active substituted 4h-pyrans using the one-pot three-component reaction of aromatic aldehydes, dimedone and malononitrile in the presence of cobalt oxide nanoparticles. co3o4 nanoparticles were used as an efficient catalyst for the synthesis of polyhydroquinoline derivatives by the reaction of aromatic aldehydes,...

triphenyl phosphine(pph3), an efficient and reusable catalyst, catalysed the synthesis of 2-amino-3-cyano-6-methyl-4-aryl-4h-pyran-5-ethylcarboxylate derivatives by one-pot condensation of aromatic aldehydes, malononitrile and ethyl acetoacetate in etoh-h2o (1:1) at reflux conditions. the results show that aromatic aldehydes containing electron-donating groups or electron-withdrawing groups cou...

the chemistry of 2-oxo-1,2,3,4-tetrahydropyrimidines began to develop toward the end of 1893 year, when the first representatives of this class compounds were reported by p. biginelli. despite prior reports of several really effective catalytic and non-catalytic approaches towards biginelli-type products, an overwhelming number of new catalysts for the biginelli reaction have been recently publ...

a mild and efficient method has been developed for the preparation of substituted coumarins from reaction of various phenols with different β-ketoesters via pechmann condensation in the presence of brønsted acidic ionic liquid (n-(4-sulfonic acid) butyl triethylammonium hydrogen sulfate) as an effective catalyst under solvent-free conditions. different phenols reacted with ethyl acetoacetate to...

zrp2o7 nanoparticles have been used as an efficient catalyst for the preparation of 2-aryl-5-methyl-2,3-dihydro-1h-3-pyrazolones by a simple one-pot four-component reaction of phenyl hydrazines, ethyl acetoacetate ,β-naphthol and benzaldehydes under microwave irradiation in good to excellent yields. when the reaction was carried out using zrocl2.8h2o, zro2 and zrp2o7 nps as the catalyst, the pr...

1-(2,4-Dichlorophenyl)-3-(4-fluorophenyl)propen-1-one (1) was prepared and reacted with an active methylene compound (ethyl cyanoacetate) in the presence of ammonium acetate to give the corresponding cyanopyridone 2. Compound 2 reacted with hydrazine hydrate, malononitrile, ethyl bromoacetate and phosphorous oxychloride to afford compounds 4 and 7-11, respectively. The 2-chloropyridine derivati...

A series of 1-(N-substituted-1H-indol-3-yl)-3-arylprop-2-ene-1-ones (2a, b-4a, b) were prepared and allowed to react with urea, thiourea or guanidine to give pyrimidine derivatives 5a, b-13a, b. Reaction of 2a, b-4a, b with ethyl acetoacetate in the presence of a base gave cyclohexanone derivatives 14a, b-16a, b. Reaction of the latter compounds with hydrazine hydrate afforded indazole derivati...