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An efficient domino approach for the synthesis of new pyrano[4,3-b]pyrazolo[4,3-e]pyridin-5(1H)-one derivatives has been developed using reusable sulfonic organic resin as catalyst in water. The unique feature of sulfonic organic resin makes the formation of pyrano[4,3-b]pyrazolo[4,3-e] pyridin-5(1H)-ones be possible, and avoids generating ring opening products. The plausible mechanism for this domino reaction is proposed.

A series of rare earth elements (REE)-modified Pt/MCM-41 catalysts were prepared. The effects of REE-doped MCM-41 on the performance of 0.2%Pt/MCM-41 and on benzene combustion were evaluated. XRD spectra and N 2 adsorption show MCM-41 with high specific surface area and large pore volume has a highly ordered hexagonal mesostructure. The UV–vis DRS show that size of Pt particles changes in the trend of small size after adding Nd, and this result is in excellent agreement with the data obtained from HRTEM-EDS. The highest catalytic activity and durability of 0.2%Pt/6%Nd/MCM-41 is attributed to an optimized Nd content, Pt particles with smaller size and high Pt dispersion on MCM-41.

We report here that the amino-group functionalized nanoporous polydivinylbenzene (PDVB-2.0-NH2, PDVB-NH2), acts as an efficient solid base for catalyzing Knoevenagel condensation, which could be synthesized from nitration of nanoporous polydivinylbenzene (PDVB), reduction in the mixture containing SnCl2 and HCl, and activated with isopropylamine. The resultant solid bases of PDVB-2.0-NH2 and PDVB-NH2 have large BET surface areas, abundant nanopores, controlled hydrophobic network and ultra-high concentrations of the amino group. The above characteristics result in their excellent activities and good recyclability for catalyzing Knoevenagel condensation of various aldehydes with malononitrile, much better than those of commercially basic resin of Amberlite-400 and Amberlite-910, which was as comparable as that of the homogeneously strong base of CaO. This work develops efficient nanoporous polymeric solid bases with controllable surface characteristics and ultra high concentrations of basic sites. (C) 2015 Elsevier B.V. All rights reserved.

An efficient, high yielding method has been developed for the synthesis of diversity tetrahydro-4 H -indol-4-one derivatives via a three component, one pot domino reaction from cyclohexane-1,3-diones, amines and nitrostyrenes using carbon functionalized with sulfonic acid group carbonaceous material as catalyst for the first time. The reaction was carried out in water, affording good to excellent yields in short time. The advantages of atom and step economy, green, and scope make this reaction a powerful tool for assembling heterocyclic scaffolds of general chemical and biomedical interest.

Crystalline mesoporous chromium oxide (P4VP–Cr2O3) was synthesized and used as carrier of metal (Cu, Mn, Co) oxides for benzene complete oxidation. Influence of the ceria promoter on catalytic performance of MnOx/P4VP–Cr2O3 was investigated. The results show that P4VP–Cr2O3 has abundant mesopores, which exhibits blocky morphology with crystal sizes ranging from 5 to 15 μm, giving a uniform pore size centered at 18.4 nm. P4VP–Cr2O3 exhibits a high degree of crystallinity, and active sites have been successfully loaded into P4VP–Cr2O3. Ceria promoter, smaller MnOx crystallites and strong interaction among the metal oxides are the key factors to enhance the catalytic activity.

Crystalline mesoporous γ-Al2O3 has been successfully synthesized under high temperature hydrothermal conditions and used as an excellent support for Pd(OAc)2. The resulting γ-Al2O3–Pd showed excellent catalytic activity for Suzuki–Miyaura cross-coupling reaction. As low as 0.2 mol% loading of Pd was needed to obtain cross-coupling products in good to excellent yields in aqueous DMF under microwave irradiation. Moreover, the novel catalyst can be easily recovered by filtration and reused without any diminishing observable activity after five runs.

Mesoporous polydivinylbenzene (PDVB) based solid acid of PDVB-SO 3 H- x s have been successfully synthesized from sulfonation of superhydrophobic PDVB. Characterizations including FT-IR spectra, N 2 isotherms and element analysis showed that PDVB-SO 3 H -x s had high BET surface areas and adjustable contents of active site. Liquid-adsorption tests showed that PDVB-SO 3 H -x s exhibited much higher adsorption capacities for various organic compounds than those of H 3 PO 40 W 12 , S-ZrO 2 , SBA-15-SO 3 H and Amberlyst 15. Interestingly, PDVB-SO 3 H -x s showed better catalytic activities and recyclability towards transesterification to biodiesel than those of Amberlyst 15, Nafion NR50 and SBA-15-SO 3 H, which will be potentially important for their widely applications for producing of biodiesel in industry.

In present work, adsorption/desorption and catalytic oxidation of three common volatile organic compounds on Na-montmorillonite, Al and AlCe pillared clays supported Pd catalysts, were investigated. The results showed that after pillaring, S BET , V micro and V meso of clays were obviously increased, which then improved the Pd dispersion. Catalysts with suitable amount and strength of acidity are fit for VOC adsorption and deep oxidation. VOC adsorption/desorption and catalytic activity results showed that catalysts with high S BET , large pore volume and suitable acidity can adsorb more VOCs, and exhibit better catalytic activity for VOC deep oxidation.

Palladium and cerium oxide promoted Co/Al2O3 catalysts were prepared and used for oxidation of benzene. Influence of Pd, Ce and Co/Ce molar ratios on the properties and catalytic performance was investigated. The results indicated that addition of palladium and cerium oxide could provide active oxygen species to cobalt oxide and make Co3O4 particles better dispersed on Al2O3, thus enhancing oxidation ability of the catalyst. High catalyst activity is mainly attributed to better dispersed Co3O4 on Al2O3, smaller Co3O4 crystallites and larger CeO2 crystallites which can strengthen the interaction among PdO, CeO2 and Co3O4.

The novel ionic liquid with both Lewis and Bronsted acid sites has been synthesized and its catalytic activities for acetalization and Michael addition were investigated carefully. The novel ionic liquid was stable to water and could be used in aqueous solution. Furthermore, the molar ratio of the Lewis and Bronsted acid sites could be adjusted according to different reactions. The results showed that the novel ionic liquid was very efficient for the traditional acid-catalyzed reactions with good to excellent yields in short time.

A novel gold-catalyzed rearrangement of alpha-hydroxy epoxides has been investigated. The reaction proceeds efficiently under mild conditions to afford unsymmetrical 1,5 or 1,6-diketones and monoketones in moderate to high yields. The selective formation of the two products could be controlled by substituents and ring strain. [GRAPHICS] Crown Copyright (c) 2009 Published by Elsevier B.V. All rights reserved.