A green and efficient protocol for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives via cyclocondensation of 5,5-dimethyl-1,3-cyclohexanedione and aromatic aldehydes in the presence of catalytic amount of 10-molybdo-2-vanadophosphoric acid under solvent-free conditions has been described. The 10-molybdo-2-vanadophosphoric acid was prepared and characterized by ...

An efficient method has been developed for the Friedländer synthesis of substituted quinolines through a condensation reaction of 2-aminoaryl ketones with α-methylene ketones in the presence of a catalytic amount of nano Fe3O4@SiO2-SO3H under solvent-free conditions at 110 °C. The reactions are completed in short times, and the products are obtained in good to excellent yields. The results reve...

A green and efficient protocol for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives via cyclocondensation of 5,5-dimethyl-1,3-cyclohexanedione and aromatic aldehydes in the presence of catalytic amount of 10-molybdo-2-vanadophosphoric acid under solvent-free conditions has been described. The 10-molybdo-2-vanadophosphoric acid was prepared and characterized by ...

Herein we explore facile synthesis of 4-(3H)-Qunazolinone derivatives, achieved by the cyclocondensation of anthranilic acid, aromatic amines and triethyl orthoformate in presence of thiamine hydrochloride (Vitamin B1) as a catalyst, using grinding method. This protocol offers several advantages such as reusability of catalyst, excellent yield, shorter reaction time and economic availability.Qu...

A sustainable catalyst for the selective oxidation of benzyl alcohol (BnOH) to benzaldehyde (BzH) was developed by mineralizing Ti(SO4)2 on graphene oxide foam (GOF) surface. The Ti(SO4)2/GOF was characterized by scanning electron microscopy (SEM), energy disperse spectroscopy (EDS), X-ray diffraction (XRD), solid-state NMR (SSNMR), thermal gravimetric analysis (TGA), infrared (IR) and BET anal...

Sulfonated-silica-coated cobalt ferrite (CoFe2O4) magnetic nanoparticles (MNPs-SiCoFe-SO3H) are efficient heterogeneous catalysts for the synthesis of 3,4-dihydropyrimidin-2(1H)-one and octahydroquinazoline derivatives in absence solvent. The effects solvent, temperature, catalyst amount on reaction investigated. easy separation, reusability catalyst, simplicity procedure, mild conditions, good...

The central theme of this article is how to explore a novel route to fabricate graphene– ZnO@SiO2 hybrid by a covalent process. The synthesis procedure consists of three-steps: (1) synthesis of ZnO nanoparticles, (2) ZnO nanoparticles modification by tetraethyl orthosilicate and (3-aminopropyl) triethoxysilane after introduction of amino groups on its surface, (3) the covalent attach...

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(...