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Catalytic Applications (catalytic + application)
Selected AbstractsDiversification of RTH-Type Zeolite and Its Catalytic Application,ANGEWANDTE CHEMIE, Issue 52 2009Toshiyuki Yokoi Dr. Metall macht's möglich: RTH-Zeolithe (siehe Bild) haben eine attraktive poröse Struktur, ihre Zusammensetzung lässt sich aber nur bedingt variieren. Metallosilicate mit RTH-Topologie sind nun über zwei Wege zugänglich; bei einem davon kann sogar auf strukturbestimmende Agentien verzichtet werden. So erhaltene Al-haltige RTH-Zeolithe waren wirksame Katalysatoren für die hoch selektive Umwandlung von Methanol in Propen. [source] ChemInform Abstract: Syntheses of Acetonitrile-Ligated Copper Complexes with Perfluoroalkoxy Aluminate as Counter Anion and Their Catalytic Application for Olefin Aziridination.CHEMINFORM, Issue 3 2009Yang Li Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Unexpected Solvent-Induced cis/trans Isomerization and Catalytic Application of a Bis-bidentate Nickel(II) Complex with N-Heterocyclic Carbene and Amido Functionalities.CHEMINFORM, Issue 13 2008Chuang-Yi Liao Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] An Efficient and Versatile Approach for the Immobilization of Carbene Precursors via Copper-Catalyzed [3 + 2]-Cycloaddition and Their Catalytic Application.CHEMINFORM, Issue 51 2007Kirsten Zeitler Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Palladium(II) and Gold(I) Complexes of a New O-Functionalized N-Heterocyclic Carbene Ligand: Synthesis, Structures, and Catalytic Application.CHEMINFORM, Issue 25 2007Lipika Ray Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A New Catalytic Application of a Keggin Acid in the Synthesis of Symmetrical Bis(indolyl)alkanes.CHEMINFORM, Issue 24 2006Manas Chakrabarty Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Novel Flower-Like Ag-SiO2 -MgO-Al2O3 Material: Preparation, Characterization and Catalytic Application in Methanol DehydrogenationCHINESE JOURNAL OF CHEMISTRY, Issue 6 2008Jing-Xia LI Abstract Catalytic direct dehydrogenation of methanol to formaldehyde was carried out over Ag-SiO2 -MgO-Al2O3 catalysts prepared by sol-gel method. The optimal preparation mass fractions were determined as 8.3% MgO, 16.5% Al2O3 and 20% silver loading. Using this optimum catalyst, excellent activity and selectivity were obtained. The conversion of methanol and the selectivity to formaldehyde both reached 100%, which were much higher than other previously reported silver supported catalysts. Based on combined characterizations, such as X-ray diffraction (XRD), scanning electronic microscopy (SEM), diffuse reflectance ultraviolet-visible spectroscopy (UV-Vis, DRS), nitrogen adsorption at low temperature, temperature programmed desorption of ammonia (NH3 -TPD), desorption of CO2 (CO2 -TPD), etc., the correlation of the catalytic performance to the structural properties of the Ag-SiO2 - MgO-Al2O3 catalyst was discussed in detail. This perfect catalytic performance in the direct dehydrogenation of methanol to formaldehyde without any side-products is attributed to its unique flower-like structure with a surface area less than 1 m2/g, and the strong interactions between neutralized support and the nano-sized Ag particles as active centers. [source] Norbornene Bidentate Ligands: Coordination Chemistry and Enantioselective Catalytic ApplicationsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2010Fernando Fernández Abstract N - and P-donor derivatives have been prepared by functionalization of a readily available norbornene precursor. Palladium catalytic systems containing these new ligands were applied in allylic substitution, and yielded high activities and excellent enantioselectivities for the allylic alkylation and amination reactions (ee up to 97,%). A full coordination analysis of the catalytic precursors including modelling studies was also carried out. [source] Synthesis and Catalytic Applications of Self-Assembled Carbon Nanofoams,ADVANCED MATERIALS, Issue 2 2008J. García-Martínez A new surfactant-templated carbon material, carbon nanofoam (CNF), has been synthesized with a semicrystalline and conductive framework, high surface area and interconnected porous structure, and prepared in a wide variety of bulk shapes and forms. CNF was also successfully applied as a support for palladium in the Heck coupling reaction. Pd/CNF catalyst exhibited negligible Pd cluster growth and agglomeration, and retained high activity even after multiple runs. [source] Monodisperse Nanoparticles of Ni and NiO: Synthesis, Characterization, Self-Assembled Superlattices, and Catalytic Applications in the Suzuki Coupling Reaction,ADVANCED MATERIALS, Issue 4 2005J. Park Monodisperse spherical Ni nanoparticles with diameters of 2 nm, 5 nm, and 7 nm were synthesized from the thermal decomposition of a Ni,oleylamine complex. Ni nanocrystal superlattices were generated via the controlled evaporation of solvent (see Figure). The nanoparticles were successfully used as catalysts for the Suzuki coupling reaction, and were readily oxidized to produce NiO nanoparticles. [source] Synthesis and Catalytic Applications of ansa Compounds with Cycloalkyl Moieties as Bridging Units: A Comparative StudyADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Alejandro Capapé Abstract The molybdenum and tungsten compounds (Mo{,5 -C5H4[CH(CH2)n]-,1 -CH}(CO)3) and (W{,5 -C5H4[CH(CH2)3]-,1 -CH}(CO)3) (2a, 3an=3; 2b, 3bn=4; 2c, 3cn=5; 2d, 3dn=6) were synthesized by reacting the spiro-bicyclic compounds 1a,d with the complex [M(CO)3(tach)] (M=molybdenum, tungsten; tach=1,3,5-trimethylhexahydro-1,3,5-triazine). NMR spectroscopy, as well as X-ray diffraction studies, confirm the formation of an intramolecular ansa bridge. The complexes display a good stability in the solid state (stable up to 180,°C under air, as determined by thermogravimetric studies) and are highly active catalysts at room temperature (molybdenum compounds) or above (tungsten compounds) in olefin epoxidation. In the case of cyclooctene as substrate, TOFs up to ca. 11800,h,1 are obtained. Moreover, most of the catalysts described here display a high selectivity in the epoxidation of cis - and trans -stilbene. In addition, the novel complexes were compared with previously synthesized related compounds, at least matching their catalytic performances. [source] Water-Soluble Group 8 and 9 Transition Metal Complexes Containing a Trihydrazinophosphaadamantane Ligand: Catalytic Applications in Isomerization of Allylic Alcohols and Cycloisomerization of (Z)-Enynols in Aqueous MediumADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 12-13 2006Abstract An optimized synthesis of the 2,4,10-trimethyl-1,2,4,5,7,10-hexaaza-3-phosphatricyclo[3.3.1.13,7]decane ligand (THPA) is described. It readily reacts with the dimers [{RuCl(,-Cl)(,6 -arene)}2] and [{MCl(,-Cl)(cod)}2] to yield the corresponding mononuclear complexes [RuCl2(THPA)(,6 -arene)] [arene=C6H6 (4a), p -cymene (4b), 1,3,5-C6H3Me3 (4c), C6Me6 (4d)] and [MCl(THPA)(cod)] [M=Rh (7a), Ir (7b)], respectively. Treatment of 4a and b with MeOTf affords the cationic derivatives [RuCl2(THPA-Me)(,6 -arene)][OTf] {arene=C6H6 (5a), p -cymene (5b); THPA-Me=1,2,4,10-tetramethyl-2,4,5,7,10-pentaaza-1-azonia-3-phosphatricyclo[3.3.1.13,7]decane}. The arene-ruthenium(II) complexes 4a,d and 5a and b are efficient catalysts for the redox isomerization of allylic alcohols into carbonyl compounds in both THF and aqueous media. The catalytic systems can be recycled by a simple extraction process and used in up to 4 consecutive runs. All the water-soluble complexes prepared in this work are able to promote the cycloisomerization of (Z)-enynols to afford furans in water, the best performance being obtained with the iridium catalyst 7b. Furthermore, 7b has shown an excellent recyclability (10 runs). This study represents the first example of iridium-catalyzed cycloisomerization of (Z)-enynols. [source] ChemInform Abstract: Mono-, Bis- and Tris-piperidine Fused Imidazolinium Salts: Their in situ Catalytic Applications for C,C Bond Formation in Aqueous SolutionsCHEMINFORM, Issue 2 2010Hayati Tuerkmen Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis, Properties, and Catalytic Applications of Caged, Compact Trialkylphosphine 4-Phenyl-1-phospha-4-silabicyclo[2.2.2]octane.CHEMINFORM, Issue 11 2009Atsuko Ochida Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Catalytic Applications of 1,2,4-Diazaphospholide-Based Ruthenium Complexes in the Heck Reaction.CHEMINFORM, Issue 14 2008Jake Yorke Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Recent Updates of Chemically Modified Electrodes in Analytical ChemistryELECTROANALYSIS, Issue 13 2003Jyh-Myng Zen Abstract This review article updates recent developments in chemically modified electrodes (CMEs) towards analytical applications for the year of 2000,2002 with 179 references. The broad topics are subdivided into four main categories: i) physisorption/chemisorption, ii) covalently linked, iii) homogenous (uniform) multilayer and iv) heterogeneous (non-uniform) multilayer CMEs. The criteria for the preparation of CMEs in elecrocatalytic systems are clearly described in Section 1. Some of the encouraging results related to Au-nanoparticles for DNA detection and new ceramic carbon, carbon nanotubes, copper-plated screen-printed and Nafion/lead ruthenate pyrochlore CMEs for catalytic application were especially discussed in this review. [source] Hierarchical Zeolite Catalysts: Zeolite Catalysts with Tunable Hierarchy Factor by Pore-Growth Moderators (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Mater. On page 3972, Pérez-Ramírez et al. introduce the hierarchy factor as a valuable descriptor to categorize hierarchical zeolites and to optimize their design for catalytic applications. They demonstrate a direct correlation between the catalytic performance of ZSM-5 in benzene alkylation and the hierarchy factor. Maximization of the hierarchy factor is achieved by enhancing the mesopore surface area without reducing the micropore volume. For this purpose, a novel desilication variant involving NaOH treatment in the presence of pore growth moderators (quaternary ammonium cations) is presented. [source] [Ru(0)]@SiO2 and [RuO2]@SiO2 Hybrid Nanomaterials: From Their Synthesis to Their Application as Catalytic Filters for Gas SensorsADVANCED FUNCTIONAL MATERIALS, Issue 23 2009Victor Matsura Abstract [Ru(0)]@SiO2 and [RuO2]@SiO2 hybrid nanomaterials are produced following a facile method consisting of the synthesis of size-controlled ruthenium nanoparticles as elemental bricks. This route takes advantage of the organometallic approach and the use of a bifunctional ligand for the synthesis of ruthenium nanoparticles from [Ru(COD)(COT)](COD,=,1,3-cyclooctadiene, COT,=,1,3,5-cyclooctatriene) as metal precursor and (PhCH2)2N(CH2)11O(CH2)3Si(OEt)3 (benzenemethanamine) as stabilizer. Hydrolysis and polycondensation steps via a sol,gel approach lead to the formation of the silica materials containing the metal nanoparticles. A final calcination step in air at 400,°C yields the [RuO2]@SiO2 nanocomposites. Such hybrid nanomaterials display a good dispersion of the nanoparticles inside the silica matrix and interesting porosity properties making them attractive materials for catalytic applications. This is shown by using [RuO2]@SiO2 hybrid nanomaterials as catalytic filters for gas sensors. [source] One-Pot Synthesis of Functional Helicoidal Hybrid Organic,Inorganic Nanofibers with Periodically Organized MesoporosityADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Frédéric Rambaud Abstract The one-pot synthesis and properties of multifunctional hybrid mesoporous organosilica fibers with helical shapes are described. These hybrid mesoporous fibers are prepared without chiral elements and functionalized with a large variety of organic R functions (R,=,alkylthiols, phenylsulfonates, alkylphosphonates, dansyl, aminopropyl, fluoroalkyl, etc.). The resulting nanomaterials are thoroughly characterized by a variety of techniques. The use of a synergetic combination of achiral molecules as co-directing structuring agents, a surfactant, and an organofunctional silica precursor R-Si(OR)3 allows, via carefully tuning of the main synthesis parameters and processing conditions, to control the shape, which is the anisotropic factor, of the hybrid nanofibers. The functionalization of the hybrid materials with fluorescent molecules (dansyl) and gold nanoparticles opens possibilities for sensor and catalytic applications, respectively. Moreover, these hybrid nanofibers can be easily transferred in organic solvents or in a "green" solvent such as water to make stable colloidal dispersions. This tunable functionality of nanofibers also allows their transferability into a variety of polymeric hosts (PVDF, PVBu, and PVP) allowing the formation of functional homogeneous nanocomposite hybrid membranes. [source] Porous Chromium Terephthalate MIL-101 with Coordinatively Unsaturated Sites: Surface Functionalization, Encapsulation, Sorption and CatalysisADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Do-Young Hong Recent ideas concerning site-selective functionalization of chromium terephtha-late MIL-101 are discussed, focusing on the utilization of unsaturated Cr(III) sites (see image). Recent advances in synthesis, selective surface functionalization, outstanding sorption properties, encapsulation of nanoobjects, and catalytic applications in MIL-101 are also discussed. [source] Ruthenium (II) complexes immobilized on swellable polyacrylate matrices: Synthesis and catalytic applicationsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2008Z. S. Liu Abstract RuH2(PPh3)4 has been immobilized on swellable polyacrylate matrices to provide heterogenized carboxylate-derivatives. These swellable polymer supported ruthenium (II) complex catalysts have been used in the transfer hydrogenation of aldehydes. Hydrogen donors are formate salt, cyclohexanol, and benzyl alcohol. The catalysts exhibit good activity for hydrogen transfer reduction of aldehydes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Synthesis, characterization and catalytic applications of tridentate Schiff base derivatives of bis and mono(cyclopentadienyl)-lanthanocene complexesCHINESE JOURNAL OF CHEMISTRY, Issue 5 2000Muhammad Yousaf Abstract Seven kinds of lanthanocene complexes were prepared by the reaction of tridentate Schiff base | N -(2-methoxyphenyl)salicylideneamine with tris(cyclopentadienyl) lanthanide tetrahydrofuranate or bis (cyclopentadienyl) lanthanide chloride tetrahydrofuranate in THF. All the complexes were characterized by MS, EA and IR respectively. The structure of |Cp2LnC14U13NO2) Ln = Sm, Dy, Y, Er| (1,4) was further confirmed by X-ray determination of Cp2Sm(C14H13NO2) (1) which indicates that the complex is monomeric in which central metal is coordinatively saturated by two cyclopentadienyl rings, two oxygens and one nitrogen of the ligand. The isomerization of 1,5-hexadiene explains that complexes (1,4) isomerize this monomer into a mixture of 1,4-hexadiene, 2,4-hexadiene, 1,3-hexadiene, methylenecyclopentane and methyl,cyclopentene. Similarity complexes |CpLn(a) C14 H13NO2) (THF) (Ln=Sm, Dy, Y, Er)| (5,7) polymerize methyl-methacrylate (MMA) to give polyMMA (PMMA) in 51.8% yield and high molecular weight (274 × 103), which shows narrow molecular weight distributions and partially syndiotactic. [source] | |||||||||||||||||||||||||