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Organic Amines (organic + amine)
Selected AbstractsA Novel Layered Bimetallic Phosphite Intercalating with Organic Amines: Synthesis and Characterization of Co(H2O)4Zn4 (HPO3) 6×C2N2H10.CHEMINFORM, Issue 25 2006Zhi-En Lin 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] Acid,Base Bifunctional Catalysis of Silica,Alumina-Supported Organic Amines for Carbon,Carbon Bond-Forming ReactionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 13 2008Ken Motokura Dr. Abstract Acid,base bifunctional heterogeneous catalysts were prepared by the reaction of an acidic silica,alumina (SA) surface with silane-coupling reagents possessing amino functional groups. The obtained SA-supported amines (SA,NR2) were characterized by solid-state 13C and 29Si,NMR spectroscopy, FT-IR spectroscopy, and elemental analysis. The solid-state NMR spectra revealed that the amines were immobilized by acid,base interactions at the SA surface. The interactions between the surface acidic sites and the immobilized basic amines were weaker than the interactions between the SA and free amines. The catalytic performances of the SA,NR2 catalysts for various carbon,carbon bond-forming reactions, such as cyano-ethoxycarbonylation, the Michael reaction, and the nitro-aldol reaction, were investigated and compared with those of homogeneous and other heterogeneous catalysts. The SA,NR2 catalysts showed much higher catalytic activities for the carbon,carbon bond-forming reactions than heterogeneous amine catalysts using other supports, such as SiO2 and Al2O3. On the other hand, homogeneous amines hardly promoted these reactions under similar reaction conditions, and the catalytic behavior of SA,NR2 was also different from that of MgO, which was employed as a typical heterogeneous base. An acid,base dual-activation mechanism for the carbon,carbon bond-forming reactions is proposed. [source] Amine-Intercalated Layered SnII Phosphates with Open-Framework StructuresEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 17 2006Padmini Ramaswamy Abstract Three new SnII phosphate materials, [NH3(CH2)3NH2(CH2)2NH2(CH2)3NH3]·2[Sn2P2O8] (I), [(N2C5H14)2][Sn4P4O16]·3H2O (II) and [(N2C5H14)][Sn2P2O8]·H2O (III), have been synthesised by means of hydrothermal methods using N,N, -bis(3-aminopropyl)ethylenediamine (BAPEN; for I) and homopiperazine (H-PIP; for II and III), respectively, as the structure-directing organic amines. The solids I,III have layered architectures. The structures of all three compounds consist of strictly alternating vertex-sharing trigonal-pyramidal SnO3 and tetrahedral PO4 moieties forming infinite layers possessing apertures bound by 4- and 8-T atoms (T = Sn, P). The distorted 4- and 8-membered apertures within the layers suggest the subtle influence of the lone-pair of electrons of SnII on the structure. The interlamellar space is occupied by the protonated organic amine molecules which interact with the framework through N,H···O hydrogen bonding. The compounds I,III bear some structural relationship to the layered zinc phosphite phases. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Supramolecular Assembly of Perylene Bisimide with , -Cyclodextrin Grafts as a Solid-State Fluorescence Sensor for Vapor DetectionADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Yu Liu Abstract A nanoscopic supramolecular aggregate is constructed from perylene bisimide-bridged bis-(permethyl- , -cyclodextrins) 1 via ,,, stacking interactions. Its self-assembly behavior in organic and aqueous solutions is investigated by UV,Vis, fluorescence, and 1H NMR spectroscopy. Transmission electron microscopy and scanning electron microscopy images show the 1D nanorod aggregation of 1, which is birefringent under crossed polarizer conditions and strongly fluorescent as depicted in the fluorescence microscopy image. X-ray powder diffraction measurements indicate that 1 forms a well-ordered crystalline arrangement with a ,,, stacking distance of 4.02,Å. Furthermore, the solid-state fluorescence sensing is explored by utilizing the poly(vinylidene fluoride) membrane-embedded 1, giving that 1, as a novel vapor detecting material, can probe several kinds of volatile organic compounds and, especially, exhibits high sensitivity to organic amines. [source] The role of the Frontier orbitals in acid,base chemistry of organic amines probed by ab initio and chemometric techniquesINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 11 2010Felipe A. La Porta Abstract The Frontier effective-for-reaction molecular orbital (FERMO) concept emerges as a powerful and innovative implement to investigate the role of molecular orbitals (MOs) applied in the description of breakage and formation of chemical bonds. In this work, theoretical calculations were carried out for conjugated acids of 18 amines and their acid,base behavior was analyzed using MO energies. We observed that highest occupied MO (HOMO) energies are inadequate to describe the acid,base behavior of these compounds. By using the FERMO concept, the reactions that are driven by HOMO, and those that are not, can be better explained, independent of the calculation method used, as independent of the calculation method used, both HF and Kohn,Sham methodologies lead to the same FERMO. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [source] The copper-containing amine oxidase from Arthrobacter globiformis: refinement at 1.55 and 2.20,Å resolution in two crystal formsACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2006David B. Langley Copper-containing amine oxidases are found in all the major kingdoms of life. They catalyse the oxidation of organic amines in the presence of molecular dioxygen to aldehydes and hydrogen peroxide. The catalytic centres contain a Cu atom and a topaquinone cofactor formed autocatalytically from a tyrosine residue in the presence of Cu and molecular oxygen. The structure of the Cu-containing amine oxidase from Arthrobacter globiformis, which was previously refined at 1.8,Å resolution in space group C2 with unit-cell parameters a = 157.84, b = 63.24, c = 91.98,Å, , = 112.0° [Wilce et al. (1997), Biochemistry, 36, 16116,16133], has been re-refined with newly recorded data at 1.55,Å resolution. The structure has also been solved and refined at 2.2,Å resolution in a new crystal form, space group C2, with unit-cell parameters a = 158.04, b = 64.06, c = 69.69,Å, , = 111.7°. [source] Acid,Base Bifunctional Catalytic Surfaces for Nucleophilic Addition ReactionsCHEMISTRY - AN ASIAN JOURNAL, Issue 8-9 2008Ken Motokura Dr. Abstract This article illustrates the modification of oxide surfaces with organic amine functional groups to create acid,base bifunctional catalysts, summarizing our previous reports and also presenting new data. Immobilization of organic amines as bases on inorganic solid,acid surfaces afforded highly active acid,base bifunctional catalysts, which enabled various organic transformations including CC coupling reactions, though these reactions did not proceed with either the homogeneous amine precursors or the acidic supports alone. Spectroscopic characterization, such as by solid-state MAS NMR and FTIR, revealed not only the interactions between acidic and basic sites but also bifunctional catalytic reaction mechanisms. [source] | ||||||||||