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An efficient, promoted three-component (2+1) catalytic reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one and arylglyoxal derivatives is described by the use of zinc oxide nanowires (ZnO NWs) as a green catalyst. By this achievement, some newly prepared bis(pyrazolyl)methane derivatives containing an aroyl group have been obtained. Starting materials were successfully condensed to obtain target products via three C-C bond formation in the presence of ZnO NWs as an efficient, cost-effective, environmentally friendly, and recyclable nanocatalyst. All synthesized products were obtained with good to excellent yields, and their structures were deduced by FTIR, [.sup.1]H NMR, and [.sup.13]C NMR spectroscopies and CHNS elemental analyses. It was shown that ZnO NWs can be separated, recovered after each run, and reused in further cycles (up to six runs) without significant loss of activity. Key words: ZnO nanowires, recyclable catalyst, green procedure, acylated bis(pyrazolyl)methanes, arylglyoxals. Nous decrivons une reaction catalytique (2+1) efficace a trois composants entre la 3-methyl-1-phenyl-2-pyrazolin-5-one et des derives d'arylglyoxal, dans laquelle nous avons employe des nanofils d'oxydes de zinc (ZnO) comme catalyseur ecologique. Ce faisant, nous avons synthetise de nouveaux derives de bis(pyrazolyl)methane contenant un groupe aroyle. Les produits de depart ont subi une condensation qui a permis d'obtenir les produits desires par formation de trois liaisons C-C en presence de nanofils de ZnO employes comme nanocatalyseur recyclable, ecologique, economique et efficace. Tous les produits synthetises ont ete obtenus avec des rendements allant de bons a excellents, et leur structure a ete determinee par les methodes spec-troscopiques de FTIR, RMN [.sup.1]H, RMN [.sup.13]C et par analyse elementaire CHNS. Les autres avantages de cette methode resident dans la capacite de reutilisation du catalyseur dans des cycles subsequents. Nous avons observe que les nanofils de ZnO pouvaient etre separes et recuperes apres chaque reaction, puis reutilises dans des cycles subsequents (jusqu'a 6) sans perte d'activite substantielle. [Traduit par la Redaction] Mots-cles: nanofils de ZnO, catalyseur recyclable, methode << propre >>, bis(pyrazolyl)methanes acyles, arylglyoxals., Introduction In recent decades, remarkable increases of environmental pollutions and their harmful effects on animals, humans, and the environment had led to increased attention in decreasing man-made pollutions, making chemical [...]

In this paper, a 3D porous polycalix functionalized with a dual Brønsted–Lewis acidic double-charged DABCO-based ionic liquid group (PC4RA@[SiPrDABCO@BuSO3H](FeCl4)) was synthesized using multiple steps, characterized, and then evaluated by spiro formation for catalytic activity. Initially, the polymeric support was modified using the silylation of its hydroxy groups with (3-chloropropyl)-trimethoxysilane as an organo-silane linker to develop PC4RA-SiPrCl. Then, it was post-functionalized using bi-functional acidic IL groups bearing double-charged diazoniabi-cyclo[2.2.2]octane tetrachloro-ferrate(III) with moving active sites of SO3H groups to deliver PC4RA@[SiPrDABCO@BuSO3H](FeCl4). In the next step, the characterization of the designed catalyst was directed by applying FT-IR, EDX, elemental mapping, WPXRD, LPXRD, FE-SEM, STA, and TEM techniques. The catalytic performance of the porous polymeric system was confirmed using the formation of spiro-fused[4H-pyran] as a highly recyclable and stable di-cationic polymer-supported acidic IL under mild conditions. [ABSTRACT FROM AUTHOR]

The synthesis of 2H-indazolo[2,1-b] phthalazine-triones and triazolo[1,2-a]indazole-triones catalyzed by 1H-1,2,4-triazole-3-thiol-functionalized core–shell Fe3O4@SiO2 magnetic nanocomposite in one-pot three-component reactions under solvent-free conditions is introduced. The catalyst was fabricated through a four-step protocol and was characterized by different techniques. The catalytic activity of nano-catalyst to generate some products was assessed. The excellent yields for all products were obtained when 15 mg of the as-prepared magnetic nanocomposite was utilized in one-pot solvent-free three-component reactions at 100 °C. The investigation of the reusability of the catalyst showed the stability of 92% after five runs. The simplicity of use and easy separation are the additional advantages of the proposed procedure. [ABSTRACT FROM AUTHOR]

The title nitrones react with cyanide ions to give benzoic acids and N-aryl-4-hydroxy-2-cyanophenylamines via two different pathways.

A capable manner for the preparation of chromeno-pyrano[2,3-b]quinoline compounds is outlined. Pyrano[3,2-c]chromene-3-carbonitriles are synthesized via the one pot three-component reaction of aryl aldehydes, malononitrile and 4-hydroxycoumarin in the presence of silica sodium carbonate (SSC) as a heterogeneous basic catalyst. Next, the prepared pyrano[3,2-c]chromene-3-carbonitrile is reacted with cyclohexanone by using silica-supported molybdic acid (SSMA) as a worthy and recyclable catalyst for producing recognized and unrecognized chromeno-pyrano[2,3-b]quinoline derivatives under solvent-free conditions in good to excellent yields. [ABSTRACT FROM AUTHOR]

In this research, the synthesis of novel indeno[1,2-b]pyrano[2,3-f]chromene-2,12(13H)-dione derivatives in the presence of a newly introduced magnetically recoverable nanosolid acid catalyst is reported. At the first, phosphoric acid-functionalized silica-coated Fe3O4 nanoparticles (Fe3O4@SiO2–(CH2)3OPO3H2) were prepared and well characterized using infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and energy-dispersive X-ray spectroscopy (EDS) techniques. Then, the catalytic activity of the prepared Fe3O4@ SiO2–(CH2)3OPO3H2 nanocatalyst was investigated for the synthesis of novel indeno[1,2-b]pyrano[2,3-f]chromene-2,12(13H)-dione derivatives via a one-pot and three-component condensation between 5,7-dihydroxy-4-methylcoumarin, indane-1, 3-dione, and various aromatic aldehydes under solvent-free condition. All the products are unknown, and their characterization was performed with the spectral data information obtained from their FT-IR, 1H and 13CNMR, elemental analysis, and their melting points. The reusability study of the introduced nanosolid acid catalyst showed that the catalytic stability is almost completely remained up to five consecutive runs. [ABSTRACT FROM AUTHOR]

An impressive procedure for synthesis of benzo[5,6]chromeno[2,3-b]quinolin derivatives is described. First, benzo[f]chromene-2-carbonitriles are synthesized from the reaction of aryl aldehydes, malononitrile, and β-naphthol in the presence of silica sodium carbonate as a heterogeneous basic catalyst. Next, the prepared benzo[f]chromene-2-carbonitriles are reacted with cyclohexanone using 10 mol% of silica tungstic acid as an efficient and recyclable catalyst to produce known and unknown benzo[5,6]chromeno[2,3-b]quinolin derivatives under solvent-free conditions in good to excellent yields. [ABSTRACT FROM AUTHOR]