Nanocrystalline ZnZr4(PO4)6 ceramics as an efficient catalyst have been used for the preparation of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates by the four component reaction of dimethylacetylenedicarboxylate, hydrazinehydrate, malononitrile and aromatic aldehydes in water at room temperature. In this research Nano-ZnZr4(PO4)6 coordinate with the active groups(...

A green and convenient method for the synthesis of 2-amino-3-phenylsulphonyl-4H-chromenes by a one-pot three-component condensation of 1-naphthol, phenylsulphonylacetonitrile and aromatic aldehydes under solvent-free conditions using potassium phosphate tribasic trihydrate as an efficient catalyst is described. The reaction of 1-naphthol with phenylsulphonylacetonitrile and various aromatic...

Nanocrystalline ZnZr4(PO4)6 ceramics as an efficient catalyst have been used for the preparation of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates by the four component reaction of dimethylacetylenedicarboxylate, hydrazinehydrate, malononitrile and aromatic aldehydes in water at room temperature. In this research Nano-ZnZr4(PO4)6 coordinate with the active groups(...

The course of the four-component reactions of (2-benzimidazolyl) acetonitrile, carbondisulfide, isothiocyanate, and sulfur and selenium, respectively, is quite different. Whereas in the case of sulfur a tetracyclic [1,3]thiazolo[4 ,5 :4,5]pyrimido[1,6-a]benzimidazol-2(3H)-thione is formed, a zwitterionic 7-(benzimidazolium-2-yl)-[1,2]thiaselenolo[2,3-b][1,2,4]thiaselenazole-6-thiolate (an azase...

We consider a four component gas undergoing a bimolecular chemical reaction of type A1 + A2 A3 + A4, described by the Boltzmann equation (BE) for chemically reactive mixtures. We adopt hard-spheres elastic cross sections and modified line-of-centers reactive cross sections depending on both the activation energy and geometry of the reactive collisions. Then we consider the hydrodynamic limit sp...

The one-pot four-component reaction of benzohydrazide (2-picolinohydrazide), acetylenedicarboxylate, isatins and malononitrile (ethyl cyanoacetate) with triethylamine as base catalyst afforded functionalized 1-benzamidospiro[indoline-3,4'-pyridines] in good yields. (1)H NMR spectra indicated that an equilibrium of cis/trans-conformations exist in the obtained products.

The Fe-MCM-22 zeolite was found to be an efficient solid heterogeneous catalyst for synthesis of dihydropyrano [2,3-c] pyrazoles via one pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehyde and malononitrile in aqueous alcohol. The catalyst was synthesized by hydrothermal method under autogenous pressure and modified by Fe (III) ion exchange. The prepared cata...

The Fe-MCM-22 zeolite was found to be an efficient solid heterogeneous catalyst for synthesis of dihydropyrano [2,3-c] pyrazoles via one pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehyde and malononitrile in aqueous alcohol. The catalyst was synthesized by hydrothermal method under autogenous pressure and modified by Fe (III) ion exchange. The prepared cata...

Co3O4/NiO@GQDs@SO3H nanocatalyst has been used as an effective catalyst for the preparation of benzopyranopyridines through a four-component reaction of salicylaldehydes, thiols and 2 equiv of malononitrile under reflux condition in ethanol. The catalyst has been characterized by FT-IR, XRD, SEM, EDS, BET, XPS, TGA and VSM. Atom economy, reusable catalyst, low catalyst loading, applicability to...