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Organic-inorganic Hybrid Materials (organic-inorganic + hybrid_material)
Selected AbstractsCrystal Structure, Solid-State NMR Spectroscopic and Photoluminescence Studies of Organic-Inorganic Hybrid Materials (HL)6[Ge6(OH)6(hedp)6]·2(L)·nH2O, L = hqn or phen,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2006Luís Mafra Abstract Two germanium,hedp4, solids with heteroaromatic amines 8-hydroxyquinoline (hqn) and 1,10-phenanthroline (phen), (HL)6[Ge6(OH)6(hedp)6]·2(L)·nH2O (L = hqn or phen), in I and II respectively, have been prepared and characterised by single-crystal XRD, thermogravimetry, FTIR and UV/Vis spectroscopy. The complex hydrogen-bond networks, particularly in compound I, have been studied by advanced high-resolution solid-state NMR spectroscopy that combines homonuclear recoupling techniques (two-dimensional 1H- 1H DQF and 1H- 1H RFDR MAS NMR) and combined rotation and multiple-pulse spectroscopy (two-dimensional 1H- 1H FS-LG, 1H- 31P FS-LG). The fine details of the crystal structure of I have been elucidated, mainly those involving the ,,, stacking of 8-hydroxyquinoline and the relative orientation of adjacent such molecules. Compound II exhibits an emission from the lowest triplet-state energy (,,,* 0-phonon transition) of the aromatic rings at 320 nm (31250 cm,1) from 14 K to room temperature. In contrast, the triplet emission of I at 530 nm (18868 cm,1) is only detected at low temperature, because of thermally activated non-radiative mechanisms. The emission spectra of I and II display a lower-energy component with a larger life time, which results from the formation of an excimer state that originated from the ,,, phenanthroline and hydroxyquinoline interactions, respectively. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Homo-coupling of Aryl Iodide and Bromide Catalyzed by Immobilized Palladium with a Bidentate Nitrogen LigandCHINESE JOURNAL OF CHEMISTRY, Issue 10 2009Xiaofang Chen Abstract The immobilized palladium onto organic-inorganic hybrid material, which contains bidentate nitrogen ligands, was a very effective catalyst for homo-coupling of aryl iodide and bromide. The protocol involved the use of N,N -dimethylacetamide as a solvent, and n -tributylamine as a base. The reaction generated the corresponding homo-coupling products in good to excellent yields at low catalyst loading (0.20 mol%). Furthermore, the silica-supported palladium catalyst could be recovered and recycled by a simple filtration of the reaction solution and used for five consecutive trials without loss of its activity. [source] Synthetic Strategies for Hybrid Materials to Improve Properties for Optoelectronic Applications,ADVANCED FUNCTIONAL MATERIALS, Issue 14 2008Olga García Abstract We report, for the first time to the best of our knowledge, a systematic study to relate the laser action from BODIPY dyes, doped into monolithic hybrid matrices, with the synthetic protocols of the final materials prepared via sol-gel. To this aim, the influence of both the hydrolysis time, increased in a controlled way, and the nature of the neutralization agent (pyridine, 3-amino-propyltriethoxy-silane (APS), N -[3-(trimethoxysilyl)propyl]-ethylene diamine (TSPDA), and N1 -[3-(trimethoxysilyl)propyl]- diethylene triamine (TSPTA) on the laser action of PM567, incorporated into hybrid matrices based on copolymers of methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA), with methyltriethoxysilane (TRIEOS) as inorganic precursor, was analyzed. The presence of the amine-modified silane TSPDA as neutralization agent, which is able at the same time to be anchored to the inorganic network enhancing the inorganic-organic compatibility through the matrix interphase, and utilization of hydrolysis times lower than 10 minutes, increased significantly the lasing efficiency and photostability of dye. The extension of this study to the laser behavior of BODIPY dyes embedded in other different hybrid materials based on hydrolyzed-condensed copolymers of MMA with 3-(trimethoxysilyl)propyl methacrylate (TMSPMA) in a 1/1 volumetric proportion, validates the generalization of the above conclusions, which provide guides for the optimization of the synthesis of organic-inorganic hybrid materials with optoelectronic innovative applications independently of their composition. [source] Hybrid Organic-Inorganic Materials Derived from a Monosilylated Hoveyda-type Ligand as Recyclable Diene and Enyne Metathesis CatalystsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2007Xavier Elias Abstract The synthesis of a monosilylated Hoveyda-type monomer is described as well as the preparation of several organic-inorganic hybrid materials derived from it by sol-gel processes and by anchoring to commercial silica gel and MCM-41. The resulting materials were treated with first and/or second generation Grubbs' catalyst to generate Hoveyda,Grubbs' type alkylidene ruthenium complexes covalently bonded to the silica matrix. These materials are efficient recyclable catalysts for the ring-closing metathesis reaction of dienes and enynes, even for the formation of tri- and tetrasubstituted olefins. [source] Hybrid-Bridged Silsesquioxane as Recyclable Metathesis Catalyst Derived from a Bis-Silylated Hoveyda-Type LigandADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2006Xavier Elias Abstract The synthesis of a bis-silylated Hoveyda-type monomer is described as well as the preparation of several organic-inorganic hybrid materials derived from it by a sol-gel process (with and without tetraethyl orthosilicate) and by anchoring to MCM-41. The resulting materials were treated with second generation Grubbs' catalyst to generate second generation Hoveyda,Grubbs-type alkylideneruthenium complexes covalently bonded to the silica matrix. These materials are recyclable catalysts for the ring-closing metathesis reaction of dienes and enynes. [source] | ||||||||||