Results 151 to 160 of about 1,117,391 (197)
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Inorganica Chimica Acta, 2002
Abstract Three silver(I) coordination complexes of crown ethers, [Ag([15]C6)(ClO4)2](THF) (1), [Ag(DB[21]C7)(H2O)]2(ClO4)2 (2) and [Ag(DB[24]C8)(CF3SO3)]2(acetone)2 (3) have been synthesized in different solvents and characterized structurally. The mononuclear complex 1 and two different dinuclear complexes 2 and 3 are shown in this work.
Ming Wen +4 more
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Abstract Three silver(I) coordination complexes of crown ethers, [Ag([15]C6)(ClO4)2](THF) (1), [Ag(DB[21]C7)(H2O)]2(ClO4)2 (2) and [Ag(DB[24]C8)(CF3SO3)]2(acetone)2 (3) have been synthesized in different solvents and characterized structurally. The mononuclear complex 1 and two different dinuclear complexes 2 and 3 are shown in this work.
Ming Wen +4 more
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Structure and stability of supramolecular crown ether complexes
Journal of Computational Chemistry, 2015Despite the fact that the complexation of ammonium cations with ionophores like crown ethers plays an important role in biological and industrial processes, there is still a lack of theoretical methods to reproduce or even predict the host–guest complex structures or their thermodynamic stabilities in an accurate manner.
Kim Julia Hintze +2 more
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Gas-phase relative stabilities of Tl + -crown ether complexes and Rb + -crown ether complexes
European Journal of Mass Spectrometry, 2018The gas-phase stabilities of Tl + -crown ether complexes and Rb + -crown ether complexes were studied using the electrospray ionization-collision-induced dissociation-tandem mass spectrometry. Tl + and Rb
Magdalena, Frańska, Anna, Michalak
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A Novel Crown Ether. 2C60 Complex
Supramolecular Chemistry, 1999The synthesis and characterisation of a novel complex formed by crown ether 2 and 2 molecules of fullerene C60 is reported.
Francisco Lara +8 more
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Complexation properties of monoaza crown ethers
Analytica Chimica Acta, 1988Abstract A series of five monoaza crown ethers with 12-crown-4 and 15-crown-5 rings were studied with respect to their complexation of Li + , Na + , K + , Ca 2+ and Sr 2+ ions in 95/5 (v/v) methanol/ water. The complexes were studied by potentiometric titrations, with pH and sodium ion-selective electrodes.
T. Wickstrøm +3 more
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Crown ether complexes of transition metals
Polyhedron, 1982Abstract When hydrated nickel (II) chloride reacts with 18-crown-6, two products are yielded: Ni2Cl2(H2O)8 Cl2. 18 C6 (compound I) and 2 NiCl2· 2H2O· 18C6 (compound II). These complexes were separately isolated and characterized by infrared spectroscopy. The crystal structure of compound I is described. It crystallizes in the triclinic system with a =
Jacques Jarrin +3 more
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Beryllium Crown Ether Complexes Reinvestigated
Zeitschrift für anorganische und allgemeine Chemie, 2018The species present in solutions of [12]crown‐4, [15]crown‐5, and [18]crown‐6 complexes with BeCl2 were investigated by 1H, 13C, and 9Be NMR spectroscopy. These are [(BeCl)([12]crown‐4)]+ (1), [(BeCl2)([15]crown‐5)] (2), and [(BeCl2)2([18]crown‐6)] (3), however in solution the majority of the crown ethers is not bound to beryllium. In case of [12]crown‐
Magnus R. Buchner, Matthias Müller
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Recueil des Travaux Chimiques des Pays-Bas, 1983
AbstractThe synthesis of phenyl‐ and tert‐butyl‐phosphadibenzo‐18‐crown‐6 and phenylphosphadibenzo‐21‐crown‐7 is described. The complexation of alkali metal cations and rhodium(I) by these macrocycles and their phosphine oxides has been studied by NMR methods.
A. van Zon, G. J. Torny, J. H. G. Frijns
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AbstractThe synthesis of phenyl‐ and tert‐butyl‐phosphadibenzo‐18‐crown‐6 and phenylphosphadibenzo‐21‐crown‐7 is described. The complexation of alkali metal cations and rhodium(I) by these macrocycles and their phosphine oxides has been studied by NMR methods.
A. van Zon, G. J. Torny, J. H. G. Frijns
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Stability and Reactivity of Crown-Ether Complexes
1980Publisher Summary This chapter describes the physical organic aspects of crown-ether chemistry. It discusses the thermodynamic and kinetic stabilities of crown-ether complexes and describes the chemical reactivity of the complexes. The term macrocyclic polyether refers to cyclic compounds having at least one oxygen donor atom.
F. De Jong, D.N. Reinhoudt
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Magnetic Resonance in Chemistry, 1992
AbstractThe preferred conformations and the complexing behaviour of 16‐ and 17‐membered dibenzo crown ethers were studied by means of both NMR spectroscopy and molecular mechanical calculations. Conclusions could be drawn about the stoichiometry and stability of the alkali metal ion corand complexes. The spin–lattice relaxation times of the crown ether
S. Stoss, W. Schroth, E. Kleinpeter
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AbstractThe preferred conformations and the complexing behaviour of 16‐ and 17‐membered dibenzo crown ethers were studied by means of both NMR spectroscopy and molecular mechanical calculations. Conclusions could be drawn about the stoichiometry and stability of the alkali metal ion corand complexes. The spin–lattice relaxation times of the crown ether
S. Stoss, W. Schroth, E. Kleinpeter
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