Single-crystal X-ray Diffraction (single-crystal + x-ray_diffraction)

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Terms modified by Single-crystal X-ray Diffraction

  • single-crystal x-ray diffraction analysis
  • single-crystal x-ray diffraction data
  • single-crystal x-ray diffraction measurement
  • single-crystal x-ray diffraction studies
  • single-crystal x-ray diffraction study
  • single-crystal x-ray diffraction techniques

  • Selected Abstracts


    Low-Alkali Metal Content in ,-Vanadium Mixed Bronzes: The Crystal Structures of ,-Kx(V,Mo)6O15 (x = 0.23 and 0.32) by Single-Crystal X-Ray Diffraction.

    CHEMINFORM, Issue 51 2007
    Michele Zema
    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]


    Two Hexanickel-Substituted Keggin-Type Germanotungstates,

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2008
    Jun-Wei Zhao
    Abstract Two new inorganic,organic hybrid germanotungstates built from trivacant Keggin fragments and in situ generated hexanickel clusters [Ni(en)2]0.5[{Ni6(,3 -OH)3(en)3(H2O)6}(B-,-GeW9O34)]·3H2O (1) and [{Ni6(,3 -OH)3(dap)3(H2O)6}(B-,-GeW9O34)]·H3O·4H2O (2) (en = ethylenediamine and dap = 1,2-diaminopropane) were hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, single-crystal X-ray diffraction and magnetic analysis. Compound 1 crystallizes in the monoclinic space group P21/n; whereas compound 2 crystallizes in the monoclinic space group P21/c. Single-crystal X-ray diffraction indicates that both contain a hexa-NiII -substituted trivacant Keggin unit [{Ni6(,3 -OH)3(L)3(H2O)6}(B-,-GeW9O34)], (L = en or dap). Magnetic susceptibility measurements show the presence of ferromagnetic coupling interactions within the hexa-NiII clusters for 1 and 2. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Investigation of structure and dynamics in the sodium metallocenes CpNa and CpNa·THF via solid-state NMR, X-ray diffraction and computational modelling

    MAGNETIC RESONANCE IN CHEMISTRY, Issue S1 2007
    Cory M. Widdifield
    Abstract Solid-state 23Na NMR spectra of two organometallic complexes, cyclopentadienylsodium (CpNa) and the tetrahydrofuran (THF) solvate of CpNa (CpNa·THF), are presented. Analytical simulations of experimental spectra and calculated 23Na electric-field gradient (EFG) tensors confirm that both complexes are present in microcrystalline samples of CpNa recrystallized from THF. For the solvate, 23Na NMR experiments at 9.4 T and 11.7 T elucidate sodium chemical shielding (CS) tensor parameters, and establish that the EFG and CS tensor frames are non-coincident. Single-crystal X-ray diffraction (XRD) experiments are used to determine the crystal structure of CpNa·THF: Cmca (a = 9.3242(15) Å, b = 20.611(3) Å, c = 9.8236(14) Å, , = , = , = 90° , V = 1887.9(5)Å3, Z = 8). For CpNa, 23Na NMR data acquired at multiple field strengths establish sodium CS tensor parameters more precisely than in previous reports. Variable-temperature (VT) powder XRD (pXRD) experiments determine the temperature dependence of the CpNa unit cell parameters. The combination of 23Na quadrupolar NMR parameters, pXRD data and calculations of 23Na EFG tensors is used to examine various models of dynamic motion in the solid state. It is proposed that the sodium atom in CpNa undergoes an anisotropic, temperature-dependent, low frequency motion within the ab crystallographic plane, in contrast with previous models. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Quest for Environmentally Benign Ligands for Actinide Separations: Thermodynamic, Spectroscopic, and Structural Characterization of UVI Complexes with Oxa-Diamide and Related Ligands

    CHEMISTRY - A EUROPEAN JOURNAL, Issue 16 2009
    Guoxin Tian Dr.
    Abstract Complexation of UVI with N,N,N,,N, -tetramethyl-3-oxa-glutaramide (TMOGA) and N,N -dimethyl-3-oxa-glutaramic acid (DMOGA; see picture) was studied in comparison with their dicarboxylate analogue, oxydiacetic acid (ODA). The stability constants, enthalpy, and entropy of complexation all decrease in the order ODA> DMOGA>TMOGA, showing that the complexation is entropy driven and the substitution of a carboxylate group with an amide group reduces the strength of complexation with UVI due to the decrease in the entropy of complexation (see figure). Complexation of UVI with N,N,N,,N, -tetramethyl-3-oxa-glutaramide (TMOGA) and N,N -dimethyl-3-oxa-glutaramic acid (DMOGA) was studied in comparison with their dicarboxylate analogue, oxydiacetic acid (ODA). Thermodynamic parameters, including stability constants, enthalpy, and entropy of complexation, were determined by spectrophotometry, potentiometry, and calorimetry. Single-crystal X-ray diffraction, EXAFS spectroscopy, FT-IR absorption spectroscopy, and laser-induced luminescence spectroscopy were used to obtain structural information on the UVI complexes. Like ODA, TMOGA and DMOGA form tridentate UVI complexes, with three oxygen atoms (the amide, ether, and/or carboxylate oxygen) coordinating to the linear UO22+ ion through the equatorial plane. The stability constants, enthalpy, and entropy of complexation all decrease in the order ODA>DMOGA>TMOGA, showing that the complexation is entropy driven and the substitution of a carboxylate group with an amide group reduces the strength of complexation with UVI due to the decrease in the entropy of complexation. The trend in the thermodynamic stability of the complexes correlates very well with the structural and spectroscopic data obtained by single-crystal X-ray diffraction, FT-IR spectroscopy, and laser-induced luminescence spectroscopy. [source]


    Thermally stable porous supramolecular frameworks based on the metal and ,,, stacking directed self-assembly of 2,6-pyridyldicarboxylic acid bis-4-pyridylamide

    JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 8 2003
    Juan C. Noveron
    Abstract We report the formation of two thermally stable supramolecular structures based on 2,6-pyridyldicarboxylic acid bis-4-pyridylamide (PyI) and bis(hexafluoroacetylacetonato)manganese(II) that exhibits a microporous structure with cavities bearing hydrogen bonding motifs that can enclathrate acetone and methanol molecules via well-positioned hydrogen bonding interactions. Single-crystal x-ray diffraction in combination with thermogravimetric analysis and X-ray powder diffraction (XRPD) studies were utilized to study the structure and thermal behavior of trans -[Mn(hfacac)2(PyI)2]·2(CH3)2CO (1) and trans -[Mn(hfacac)2(PyI)2]·2CH3OH (2). Our studies indicated that 1 and 2 are isostructural with respect to their supramolecular assembly and trap solvent molecules along the crystallographic b direction via the inwardly directed hydrogen bonding motifs of the PyI component. These solvent molecules can be thermally removed to generate a crystalline material with micropores bearing hydrogen bonding rich sites within an overall supramolecular matrix similar to 1 and 2. The removal of the guest solvent molecules is reversible and can be followed with XRPD. Copyright © 2003 John Wiley & Sons, Ltd. [source]


    Flux growth and characterization of Ti- and Ni-doped forsterite single crystals

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 5 2009
    A. Bloise
    Abstract Forsterite monocrystals doped with Ti and Ni were grown by the flux growth technique. A suitable mixture of flux (MoO3, V2O5, Li2CO3) and nutrient was slowly cooled down to 750 °C from 1250 °C or 1350 °C. The crystals were then characterized by powder and single-crystal X-ray diffraction, scanning electron microscopy and differential scanning calorimetry (DSC). Variations observed in crystal size were attributed by both the varying experimental conditions in which they had been obtained, and to the amount of Ni substituted for Mg in the structure. High abundances of doped forsterite required a cooling rate of 1.8 K h -1. These synthetic, well-characterized Ti and Ni doped forsterite crystals may have potential for exploitation in industrial fields. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Structural and spectroscopic study of Mg13.4(OH)6(HVO4)2(H0.2VO4)6

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 11 2008

    Abstract Single-crystals of the polar compound magnesium hydrogen vanadate(V), Mg13.4(OH)6(HVO4)2(H0.2VO4)6, were synthesized hydrothermally. It represents the first hydrogen vanadate(V) among inorganic compounds. Its structure was determined by single-crystal X-ray diffraction [space group P 63mc, a = 12.9096(2), c = 5.0755(1) Å, V = 732.55(2) ų, Z = 1]. The crystal structure of Mg13.4(OH)6(HVO4)2(H0.2VO4)6 consists of well separated, vacancy-interrupted chains of face sharing Mg2O6 octahedra, with short Mg2,Mg2 distances of 2.537(1) Å, embedded in a porous magnesium vanadate 3D framework having the topology of the zeolite cancrinite. All three hydrogen positions in the structure were confirmed by FTIR spectroscopy. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Flux growth of straw-like rutile monocrystals

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2008
    A. Bloise
    Abstract Millimetric straw-like rutile monocrystals were grown by the flux growth technique. A suitable mixture of flux (MoO3, V2O5, Li2CO3) and amorphous TiO2 gel was slowly cooled down to 750°C from 1250°C or 1350°C. The best yields of straw-like rutile were obtained with a nutrient/flux ratio and a cooling rate in the range 0.015-0.006 and 1.8-1.9 K h -1, respectively. The hollowed crystals were characterized by powder and single-crystal X-ray diffraction, scanning electron microscopy, microthermometry, and µ-Raman spectroscopy. As for skeletal crystal, the formation of axial canals in rutile is attributed to a lack of nutrient due to the viscosity of the melt and the high growth rate along [001]. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Tetranuclear Manganese Complexes with [MnII4] and [MnII2MnIII2] Units: Syntheses, Structures, Magnetic Properties, and DFT Study,

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 28 2010
    Lucjan B. Jerzykiewicz
    Abstract Two tetranuclear manganese compounds, [Mn4(,3,,2 -L)4Br4(LH)4] (1) and [Mn4(,3,,2 -L)2(,,,2 -L)4L2Br2] (2), with cubane and defect dicubane-like cores were synthesized and characterized by single-crystal X-ray diffraction, magnetic measurements, and DFT calculations (LH = 2-methoxyethanol). The magnetic properties of the resulting [Mn4] building blocks are presented and discussed in detail. In particular, in 2 the MnIII,O,MnIII angle 103.12(8)° is the largest observed to date for such a system. The conjunction of antiferromagnetic and ferromagnetic interactions within the tetranuclear mixed-valent MnII2MnIII2 complexes results in an unusual ST = 1 ground state. [source]


    Systematic Hydrothermal Investigation of Metal Phosphonatobenzenesulfonates by High-Throughput Methods

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2010
    Palanikumar Maniam
    Abstract A high-throughput (HT) investigation using the rigid bifunctional ligand 4-phosphonobenzenesulfonic acid, H2O3P-C6H4 -SO3H (H3L), generated five new phosphonatobenzenesulfonates with copper(II) or lead(II) ions. A comprehensive HT study comprising the screenings of different metal ions, metal salt types and the synthesis optimization were conducted whereby the influence of pH and molar ratios M2+/H3L were investigated. The HT-study led to five new compounds Pb2[(O3P-C6H4 -SO3)(OH)] (1), Cu1.5[(O3P-C6H4 -SO3)(H2O)] (2), NaCu(O3P-C6H4 -SO3)(H2O)3 (3), Cu2[(O3P-C6H4 -SO3)(OH)(H2O)] (4) and Cu3[(O3P-C6H4 -SO3)2(H2O)2] (5). Metal ion screening showed lead(II) and copper(II) to be suitable metal ions. The utilization of discovery and focused arrays allowed to determine the optimal formation fields of the respective compounds. The crystal structures were determined from single-crystal X-ray diffraction and revealed the presence of various MOx polyhedra that form clusters, chains or layers which are connected through the organic linker. IR spectra, thermogravimetric studies, magnetic susceptibility measurements and elemental analyses were conducted to further characterize the compounds 1, 3, 4 and 5. [source]


    A ,3 -Alkoxo-Bridged Tetranuclear [Cu4L2] Copper(II) Complex of a Hexadentate N2O4 Donor Ligand with a [6 + 0] Cu4O4 Cubane Core: Synthesis, Crystal Structure, and Magnetic Properties

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 22 2010
    Dipankar Maity
    Abstract A novel hexacoordinating non-Schiff base ligand (H4L) with N2O4 donor atoms has been synthesized by simple Mannich reactions. The use of this ligand with Cu(ClO4)2·6H2O in different molar ratios as well as pH leads to the formation of a mononuclear species and a tetranuclear CuII complex possessing a cubane [Cu4L2] core with almost equal Cu···Cu separation. In the presence of an excess amount of copper(II) ions and triethylamine at reflux, the mononuclear [CuH2L] species can be converted into the tetranuclear one, whereas the reverse process was not observed even after prolonged reaction time. Both the complexes have been characterized by single-crystal X-ray diffraction and magnetic measurements. Magnetic studies reveal that complex 1 displays a paramagnetic Curie-type behavior whereas 2 displays a singlet-spin ground state induced by strong intramolecular antiferromagnetic interactions. [source]


    Lithiation of a Cyclen-Derived (NNNN) Macrocycle and Its Reaction with n -Butyllithium

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2010
    Sabine Standfuss
    Abstract Cyclic polyamine 1,4,7-trimethyl-1,4,7,10-tetraazacyclododecane, (Me3TACD)H (1), was metalated with n -butyllithium in pentane to give [Li2(Me3TACD)2] (2). The structure of this compound is dimeric in the solid state as shown by single-crystal X-ray diffraction. With an excess of nBuLi, nBuLi is incorporated into the product. Depending on the stoichiometry, the compounds [Li3(nBu)(Me3TACD)2] (3) or [Li4(nBu)2(Me3TACD)2] (4) are formed. As shown by single-crystal X-ray diffraction, both molecular structures show a ladder motif. (Me3TACD)H reacted with NaI/Na2CO3 in acetonitrile to give benzene-soluble [NaI(Me3TACD)H] (5). [source]


    1,3,5-Triazapentadiene Nickel(II) Complexes Derived from a Ketoxime-Mediated Single-Pot Transformation of Nitriles

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2010
    Maximilian N. Kopylovich
    Abstract A series of cationic (2+) [Ni{HN=C(R)NHC(R)=NH}2](X)2 {R = 4-(Cl)C6H4 (1), 3-(NC)C6H4 (3), 4-(NC)C6H4 (4) and Me (7); X = Cl, (1, 3, 4) or MeCOO,·H2O (7)} and neutral [Ni{HN=C(R)NC(R)=NH}2](solvate) {R = 3-(Cl)-4-py (2), 3-py (5) and 4-py (6); solvate = MeOH and/or H2O; py = pyridyl} N,N -chelating bis(1,3,5-triazapentadiene/ato)nickel(II) [Ni(tap)2]2+/0 complexes has been easily generated by a ketoxime-mediated single-pot reaction of a nickel(II) salt [NiCl2·2H2O or Ni(MeCOO)2·4H2O] with 4-chlorobenzonitrile, isophthalonitrile, terephthalonitrile, acetonitrile, 2-chloro-4-cyanopyridine, 3-cyanopyridine or 4-cyanopyridine, respectively. The obtained compounds have been characterized by IR, 1H and 13C{1H} NMR spectroscopy, FAB-MS(+) or ESI-MS(+), elemental analyses and single-crystal X-ray diffraction [for 7 and solvated mono- {1a·(Me2CO)0.33·(MeOH)0.67} and bis-deprotonated (2b·2Me2CO, 4b·CHCl3, 5b·Me2CO and 6b·MeOH) products, formed upon recrystallization of 1, 2, 4, 5 and 6, respectively]. The crystal structures of all compounds bear similar monomeric Ni(tap)2 units with a nearly square-planar geometry. In addition, the structure of 7 features the formation of infinite 1D zig-zag water,acetate chains {[(H2O)2(MeCOO)2]2,}n, which multiply interact with the [Ni(tap)2]2+ cations to generate a 2D hydrogen-bonded supramolecular assembly. [source]


    Heteroleptic Guanidinate- and Amidinate-Based Complexes of Hafnium as New Precursors for MOCVD of HfO2

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2010
    Ke Xu
    Abstract The synthesis and characterization of four new heteroleptic complexes [Hf{,2 -(iPrN)2CNMe2}2Cl2] (1), [Hf{,2 -(iPrN)2CNMe2}2Me2] (2), [Hf{,2 -(iPrN)2CMe}2Cl2] (3), and [Hf{,2 -(iPrN)2CMe}2Me2] (4) are reported. All the complexes were characterized by spectroscopic methods, while compounds 1,3 were further examined by single-crystal X-ray diffraction, revealing that the complexes are monomers with the hafnium center in a distorted octahedral geometry. The thermal properties of the chlorine-free complexes (2, 4) were examined to determine their suitability for metalorganic chemical vapor deposition (MOCVD) applications, and compound 2 showed good volatility and thermal stability. On the basis of these results, compound 2 was selected for MOCVD of HfO2 with oxygen as oxidant. Depositions were carried out on Si(100) substrates in the temperature range 300,700 °C. The as-deposited HfO2 films crystallized in the monoclinic phase at temperatures above 500 °C, and the composition analysis determined by Rutherford back-scattering (RBS) and X-ray photoelectron spectroscopy (XPS) revealed that the films were stoichiometric and free of carbon. Thus, alkylguanidinatohafnium complex 2 is a promising precursor for growing HfO2 films in a wide temperature range with the desired stoichiometry, because of its adequate volatility, sufficient temperature window between vaporization and decomposition, as well as its ability to decompose cleanly in the presence of oxygen. [source]


    A Family of 1,1,3,3-Tetraalkylguanidine (H-TAG) Solvated Zinc Aryloxide Precatalysts for the Ring-Opening Polymerization of rac -Lactide

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2010
    Julia J. Ng
    Abstract Reaction of [Zn(,-TAG){N(SiMe3)2}]2 {TAG = N=C[N(CH2CH3)2N(CH3)2] (DEDMG), N=C{[NCH2CH2CH2CdH2(N,Cd)]N(CH2CH3)2} (DEPYRG) and N=C{[NCH2CH2CH2CH2CeH2(N,Ce)]N(CH2CH3)2} (DEPIPG)} with 2 equiv. of ethanol (EtOH) and 2 equiv. of HOAr {OAr = OC6H3(CMe3)-2-(CH3)-6 (BMP) or OC6H2[C(CH3)3]2 -2,6-(CH3)-4 (4MeDBP)} results in dizinc alkoxides with the general formula [Zn(,-OEt)(OAr)(H-TAG)]2 (1,3). Et2Zn was additionally treated with 2 equiv. of 1,1,3,3-tetramethylguanidine (H-TMG) and H-BMP or HOC6H3(C6H5)2 -2,6 to yield [Zn(BMP)2(H-TMG)2] (4) and [Zn{OC6H3(C6H5)2 -2,6}2(H-TMG)2] (5). Complexes 1, 2, 4, and 5 were characterized by single-crystal X-ray diffraction. Polymerization of rac -lactide with 1,5 and [Zn(,-OMe)(4MeDBP)(H-TMG)]2 (6) were found to generate polylactide (PLA). The bulk powders for all complexes were found to be in agreement with the crystal structures based on elemental analyses, FTIR spectroscopy, and 1H and 13C NMR spectroscopic studies. [source]


    Mono(aryloxido)Titanium(IV) Complexes and Their Application in the Selective Dimerization of Ethylene

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2009
    Jean-Benoit Cazaux
    Abstract We report on the synthesis of mono(aryloxido)titanium(IV) complexes of general formula {Ti[O(o -R)Ar]X3}, with X = OiPr, ArO = 2- tert -butyl-4-methylphenoxy and R = CMe3 (2a), CMe2Ph (2b) and CH2NMe2 (2c). Attempts to reach pure mono(aryloxido) complexes when R = CH2NMe(CH2Ph) (2d) or CH2N(CH2Ph)2 (2e) were unsuccessful. When R = CH2OMe, the analogous mononuclear complex was not obtained, and instead, a dinuclear complex [(2- tert -butyl-4-methyl-6-methoxymethylphenoxy) TiCl(OiPr)(,2 -OiPr)2TiCl(OiPr)2] (3) was formed. Complexes 2b and 3 were characterized by single-crystal X-ray diffraction. The former contains a tetrahedrally coordinated TiIV centre, whereas in the latter the aryloxido ligand behaves as a chelating,bridging ligand between the two, chemically very different metal centres that form two face-sharing octahedra. Different synthetic approaches starting from [Ti(OiPr)4] or [TiCl(OiPr)3] were evaluated and are discussed. The hemilabile behaviour of the aryloxido ligand resulting from reversible coordination of its side arm was studied by variable-temperature 1H NMR spectroscopy for 2c (R = CH2NMe2). Complexes 2a,d were contacted with ethylene and AlEt3 as cocatalyst. When activated with AlEt3 (3 equiv.) at 20 bar and 60 °C, complex 2c exhibits interesting activity (2100 g/gTi/h) for the selective dimerization of ethylene to 1-butene (92,% C4=; 99+% C4=1). Noticeable differences in catalyst activity were observed when the R group was modified. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    The Variable Binding Modes of Phenylbis(pyrid-2-ylmethyl)phosphane and Bis(pyrid-2-ylmethyl) Phenylphosphonite with AgI and CuI

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2009
    Fernando Hung-Low
    Abstract A series of new bridging phosphane and phosphonite structures forming three- and six-membered rings with the metal centers were synthesized and characterized. The resulting compounds of phenylbis(pyrid-2-ylmethyl)phosphane (1) with the silver(I) salts of trifluoroacetate (tfa,), tetrafluoroborate (BF4,), and trifluoromethanesulfonate (OTf,), and copper tetrakis(acetonitrile) hexafluorophosphate (PF6,) shows the flexibility of the ligand by displaying different coordination modes associated with the electronic and structural characteristics of the corresponding anion. Accordingly, ligand 1 in these complexes displays two different binding modes. With Agtfa and AgBF4 compounds 3 and 4 are obtained where the ligand chelates to two silver atoms that exhibit normalAg,Ag contacts in the range of 2.9 Å. When AgOTf or Cu(NCCH3)4PF6 are used, one molecule of 1 bridges the metal centers through a phosphorus atom while another is terminally bound. This induces short M,M distances of 2.6871 and 2.568 Å for 5 and 6, respectively. Similarly, the coordination behavior of the heterofunctional bis(pyrid-2-ylmethyl) phenylphosphonite ligand (2) is reported with Cu(NCCH3)4PF6 (7) and AgBF4 (8) to form two novel discrete molecules. In these complexes 2 coordinates through the P and N atoms, with the difference that in 7 the O atom of one of the carbinol arms is also bound to the Cu. Elemental analysis, variable-temperature multinuclear NMR spectroscopy, single-crystal X-ray diffraction, and low-temperature luminescence studies were carried out to fully characterize the compounds. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    Synthesis and Cytotoxicity Studies of Fluorinated Derivatives of Vanadocene Y

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2009
    Brendan Gleeson
    Abstract From the reaction of 6-(2-fluoro-4-methoxyphenyl)fulvene (1a), 6-(3-fluoro-4-methoxyphenyl)fulvene (1b) and 6-[4-(trifluoromethoxy)phenyl]fulvene (1c) with LiBEt3H, lithiated cyclopentadienide intermediates (2a,c) were synthesised. These intermediates were then transmetallated to vanadium with VCl4 to yield the benzyl-substituted vanadocenes bis[(2-fluoro-4-methoxybenzyl)cyclopentadienyl]vanadium(IV) dichloride (3a), bis[(3-fluoro-4-methoxybenzyl)cyclopentadienyl]vanadium(IV) dichloride (3b), and bis[(4-trifluoromethoxybenzyl)cyclopentadienyl]vanadium(IV) dichloride (3c). The three vanadocenes 3a,c were characterised by single-crystal X-ray diffraction. All three vanadocenes had their cytotoxicity investigated through MTT-based preliminary in-vitro testing on the LLC-PK and Caki-1 cell lines in order to determine their IC50 values. Vanadocenes 3a,c were found to have IC50 values of 6.0 (+/,4), 35 (+/,7) and 13 (+/,3) ,M on the LLC-PK cell line and IC50 values of 78 (+/,11), 18 (+/,16) and 2.2 (+/,0.5) ,M on the Caki-1 cell line respectively. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    Synthesis and Characterization of Hypervalent Organoantimony(III) Compounds Containing the [2-(Me2NCH2)C6H4]2Sb Fragment

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2009
    Laura M. Opris
    Abstract Compounds containing the [2-(Me2NCH2)C6H4]2Sb moiety were prepared by using R2SbX [X = Cl (1), Br (2)] as starting materials. The reaction of 1 with Me3SiCH2MgCl gave the mixed alkyl,aryl stibine R2SbCH2SiMe3 (3). Reduction of 2 with Mg in thf followed by in situ air oxidation or treatment with S8 resulted in the isolation of (R2Sb)2E [E = O (4), S (5)]. Compound 5 is also formed from R2SbCl and Na2S. The reaction of 4 with [W(CO)5(thf)] gives the unexpected complex [(R2SbOH)W(CO)5] (6). The new compounds were investigated by IR, 1H, and 13C NMR spectroscopy, as well as by mass spectrometry. The structures of 3,6 were determined by single-crystal X-ray diffraction. For compounds 3,5, both nitrogen atoms from the pendant arms are involved in intramolecular N,Sb coordination, which results in distorted square-pyramidal (C,N)2SbC or (C,N)2SbE (E = O, S) cores. By contrast, in 6 only one nitrogen atom is strongly coordinated to the antimony center, whereas the second nitrogen atom is involved in N···H,O bonding. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    Platinum(IV) Complexes of 3- and 4-Picolinic Acids Containing Ammine or Isopropylamine Ligands , Synthesis, Characteri­zation, X-ray Structures, and Evaluation of Their Cytotoxic Activity against Cancer Cell Lines,

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 30 2008
    María J. Macazaga
    Abstract The preparation and characterization of the new complexes trans -[PtCl4(NH3)(3-picolinic acid)] (1), trans -[PtCl4{NH2CH(CH3)2}(3-picolinic acid)] (2), trans -[PtCl4(NH3)(4-picolinic acid)] (3), and trans -[PtCl4{NH2CH(CH3)2}(4-picolinic acid)] (4) are described. The main structural feature of these complexes is the presence of ligands capable of multiple hydrogen-bonding interactions. Crystals of 1, 2, 3, and 4 suitable for single-crystal X-ray diffraction were grown, and the molecular structures of these compounds are discussed. In contrast to the inactive parent PtII complexes, the PtIV complexes displayed cytotoxic activity against various cancer cell lines used at the National Cancer Institute (NCI) for in vitro screens. Once more, the isopropylamine derivatives showed the best cytotoxicity values. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Two Hexanickel-Substituted Keggin-Type Germanotungstates,

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2008
    Jun-Wei Zhao
    Abstract Two new inorganic,organic hybrid germanotungstates built from trivacant Keggin fragments and in situ generated hexanickel clusters [Ni(en)2]0.5[{Ni6(,3 -OH)3(en)3(H2O)6}(B-,-GeW9O34)]·3H2O (1) and [{Ni6(,3 -OH)3(dap)3(H2O)6}(B-,-GeW9O34)]·H3O·4H2O (2) (en = ethylenediamine and dap = 1,2-diaminopropane) were hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, single-crystal X-ray diffraction and magnetic analysis. Compound 1 crystallizes in the monoclinic space group P21/n; whereas compound 2 crystallizes in the monoclinic space group P21/c. Single-crystal X-ray diffraction indicates that both contain a hexa-NiII -substituted trivacant Keggin unit [{Ni6(,3 -OH)3(L)3(H2O)6}(B-,-GeW9O34)], (L = en or dap). Magnetic susceptibility measurements show the presence of ferromagnetic coupling interactions within the hexa-NiII clusters for 1 and 2. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Nitroamino Triazoles: Nitrogen-Rich Precursors of Stable Energetic Salts

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2008
    Yangen Huang
    Abstract 1-Nitroamino-1,2,3-triazole (5) was synthesized and its zwitterionic structure was established using single-crystal X-ray diffraction. The calculated detonation properties for 4-nitroamino-1,2,4-triazole (2) (P = 33.4 GPa, vD = 8793 m/s) and 1-nitroamino-1,2,3-triazole (5) (P = 33.0 GPa, vD = 8743 m/s) are comparable with RDX. A new family of energetic salts 7,21 based on either the 1-nitroamino-1,2,3-triazolate or the 4-nitroamino-1,2,4-triazolate anion were prepared and characterized by vibrational spectroscopy (IR), multinuclear NMR spectra, elemental analyses, density, TGA and DSC. The heats of formation (,fH°298) and detonation properties for these stable salts were calculated using Gaussian 03 and Cheetah 4.0, respectively. Comparison of the properties of the 1,2,3- and 1,2,4-triazolate salts indicates that while the 1,2,4-derivatives are more stable thermally, the 1,2,3-analogs invariably have higher heats of formation. In contrast to its salts, 1-nitroamino-1,2,3-triazole (5) is extremely shock-sensitive with an impact sensitivty of <1 J. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Guest-Inclusion Behavior of Double-Strand 1D Coordination Polymers Based on N,N, -Type Schiff Base Ligands

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2008
    Qing Wang
    Abstract Four double-strand one-dimensional (1D) coordinationpolymers, namely, {[Ni(N3Py)2(NO3)2]·(C6H6)x·C2H5OH}n (1), [Cd(ImBNN)2(CH3C6H4SO3)2]n (2), {[Co(N3OPy)2(H2O)2](ClO4)2·C6H6·H2O}n (3), and {[Co(N3OPy)2(H2O)2](ClO4)2·(C8H10)x}n (4) were obtained from the assembly of three N,N, -type Schiff base ligands, 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene (N3Py), 2,5-bis(4,-(imidazol-1-yl)benzyl)-3,4-diaza-2,4-hexadiene (ImBNN), and bis[4-(3-pyridylmethylenemino)phenoxy]methane (N3OPy), with transition-metal ions. All complexes were characterized by single-crystal X-ray diffraction, X-ray powder diffraction, and FTIR measurements. The guest-inclusion behavior of these complexes were investigated by thermogravimetric and X-ray powder diffraction analyses. The structural relationship between the ligands and the cavity sizes and packing fashions have been discussed to elucidate the distinctive guest-inclusion behavior of these complexes.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Synthesis, Characterization, and Sensitizing Properties of Heteroleptic RuII Complexes Based on 2,6-Bis(1-pyrazolyl)pyr­idine and 2,2,-Bipyridine-4,4,-dicarboxylic Acid Ligands

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 36 2007
    Athanassios I. Philippopoulos
    Abstract Starting from the Ru(bpp)Cl3 precursor (1), a family of novel heteroleptic RuII complexes of the general formulae [Ru(bpp)(dcbpyH)(X)] [X = Cl, (2a), NCS,, (3)] and Na[Ru(bpp)(dcbpy)(CN)] (4) with the ligands 2,6-bis(1-pyrazolyl)pyridine (bpp) and 2,2,-bipyridine-4,4,-dicarboxylic acid (dcbpyH2) has been synthesized, spectroscopically characterized, and attached to nanocrystalline TiO2 electrodes to be tested as solar cell sensitizers. Addition of HCl to (2a) led to the corresponding cationic derivative [Ru(bpp)(dcbpyH2)Cl]Cl (2b). All complexes were characterized by FT-IR, FT-Raman, UV/Vis, 1H NMR spectroscopy, elemental analysis, and mass spectrometry. Complex 4 and the previously reported [Ru(bdmpp)(dcbpyH2)Cl](PF6) (5) [bdmpp is 2,6-bis(3,5-dimethyl-1-pyrazolyl)pyridine] were characterized by single-crystal X-ray diffraction. The photo-electochemical properties of the dyes 2,4 were investigated and the efficiency of the corresponding dye-sensitized solar cells was compared to the sensitizing performance of the cis -[Ru(dcbpyH)2(NCS)2](NBu4)2 (N719) dye.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    Optical, Magnetic and Structural Properties of the Spin-Crossover Complex [Fe(btr)2(NCS)2]·H2O in the Light-Induced and Thermally Quenched Metastable States

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 36 2007
    Vincent Legrand
    Abstract [Fe(btr)2(NCS)2]·H2O [btr = 4,4,-bis(1,2,4-triazole)] is thearchetype of highly cooperative and low-dimensional spin-crossover complexes, which exhibit low-spin (LS) to high-spin (HS) light-induced conversion at very low temperature. The structural reorganizations related to the light-induced and thermally induced LS,HS transitions were characterized by single-crystal X-ray diffraction below the relaxation temperature (T = 15 K < TLIESST) and at 130 K within the thermal hysteresis loop. We show that the LIESST and thermal spin transitions lead to the same structural variations, namely an elongation of the Fe,N bonds by 0.18 Å (Fe,NNCS) and 0.20 Å (Fe,Nbtr), on going from LS to HS, together with a reorientation of the NCS group by nearly 13°. The atomic displacement amplitudes, derived from the crystal structures, indicate lattice vibration modes of larger amplitudes and correlatively lower vibration frequencies in the HS state. The deformation of the crystal lattice as a function of temperature and laser excitation was quantitatively analyzed in terms of the HS and LS thermal-expansion (,HS and ,LS) and spin-transition spontaneous-strain (,) tensors. The eigendirections and eigenvalues of the , and , tensors correlate well with the weak and strong interactions in the solid and are responsible for the high cooperativity and low-dimensional behaviour. Magnetic and spectroscopic measurements were performed in all the different spin states and related to the structural findings. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    Crystal Structure and Surface Photovoltage Properties of MnII Coordination Supramolecules

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2007
    Li-Ping Sun
    Abstract Three MnII coordination supramolecular complexes [Mn(pdc)(H2O)]n1, {[Mn(pdc) (phen)(H2O)]·3H2O}n2, and {[Mn(cyan)2(H2O)4]·2HCl·2(Hcyan)} 3 (H2pdc = pyridine-2,3-dicarboxylic acid, Hcyan = cyanuric acid, phen = 1,10-phenanthroline) were hydrothermally synthesized and their structures determined by single-crystal X-ray diffraction. The pdc group in complex 1 bridges the MnII ions to form an infinite 3D structure. In complex 2, the MnII ion is bridged to a 1D infinite chain by pdc groups and the chain is further connected to a 2D structure by hydrogen bonds. The 3D structure of complex 3 is formed by hydrogen bonds and O···Cl weak interactions. Surface photovoltage spectroscopy (SPS) of complexes 1,3 indicate that they all possess positive SPV response in the range of 300,800 nm and show p -type semiconductor characteristic. The intensities of the SPV responses are obviously different, and this can mainly be attributed to the differences in their structures. Field-induced surface photovoltage spectroscopy (FISPS) of complexes 1,3 confirms their p -type semiconductor characteristic.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    Transition-Metal (MnII and CoII) Complexes with the Heteropolymolybdate Fragment [AsVMo9O33]7,: Crystal Structures, Electrochemical and Magnetic Properties

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 17 2007
    Yanyan Yang
    Abstract Two novel heteropolymolybdates, [(CH3)4N]8n[M(H2O)5]2n(H3O)2n[{M(H2O)5}2(MAsVMo9O33)2]n[M(H2O)4(MAsVMo9O33)2]n·20nH2O (M = Mn2+, 1; M = Co2+, 2), constructed from the new fragment (AsVMo9O33)7, and a transition metal have been synthesized in aqueous solution and characterized by elemental analysis, IR spectroscopy, thermal gravimetric analysis, and single-crystal X-ray diffraction. Structurally the title complexes resemble a sandwich-type complex because they involve the coordination of two transition metals to two [AsVMo9O33]7, fragments, which derive from the well-known B -, - Keggin structure. Compounds 1 and 2 exhibit a one-dimensional chain-like framework [M(H2O)4(MAsVMo9O33)2]8n, with isolated {[M(H2O)5]2(MAsVMo9O33)2}6, units residing among the chains. The magnetic properties of the two complexes were investigated to indicate typical antiferromagnetic interactions through the MnII,O,MnII bridge unit for complex 1 and the CoII,O,CoII bridge unit for complex 2. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    Synthesis, Coordination and Catalytic Utility of Novel Phosphanyl,ferrocenecarboxylic Ligands Combining Planar and Central Chirality

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2007
    Martin Lama
    Abstract The chiral ferrocene derivative (R,Rp)-2-[1-(diphenylphosphanyl)ethyl]ferrocenecarboxylic acid (1) is prepared together with selected derivatives resulting from modification at the phosphane moiety [P -oxide (5) and P -sulfide (4)] and the carboxyl group {amides bearing benzyl (6) and (R)- or (S)-1-phenylethyl substituents [(R)- 7 and (S)- 7] at the amide nitrogen atom}. Acid 1 and amide 6 are studied as ligands in rhodium and palladium complexes. Bridge cleavage of the dimer [{Rh(,-Cl)Cl(,5 -C5Me5)}2] with 1 gives [RhCl2(,5 -C5Me5)(1 -,P)] (9) containing P-monodentate 1, which undergoes smooth conversion to the (phosphanylalkyl)ferrocenecarboxylato complex [RhCl(,5 -C5Me5){Fe(,5 -C5H5)(,5 -C5H3 -1-CH(Me)PPh2 -2-COO-,2O,P}] (10) upon treatment with silica gel or alumina. Yet another O,P -chelate complex,[Rh{Fe(,5 -C5H5)(,5 -C5H3 -1-CH(Me)PPh2 -2-COO-,2O,P}(CO)(PCy3)] (11; Cy = cyclohexyl) is obtained directly by an acid-base reaction between the acetylacetonato complex [Rh(acac)(CO)(PCy3)] and 1. Amide 6 reacts with [{Pd(,-Cl)(,3 -C3H5)}2] to give the expected phosphane complex [PdCl(,3 -C3H5)(6 -,P)] (12), while the replacement of the cyclooctadiene (cod) ligand in [PdCl(Me)(cod)] affords the chelate complex [PdCl(Me)(6 -,2O,P)] (13). All compounds are characterised by spectroscopic methods and the solid-state structures of 5, 9, 11, 13, (R,Sp)-2-[1-(diphenylphosphoryl)ethyl]-1-[N -(R)-(1-phenylethyl)carbamoyl]ferrocene [(R)- 8; phosphane oxide from (R)- 7], and the synthetic precursors (R,Sp)-1-bromo-2-[1-(diphenylphosphanyl)ethyl]ferrocene (2) and (R,Sp)-1-bromo-2-[1-(diphenylthiophosphoryl)ethyl]ferrocene (3) determined by single-crystal X-ray diffraction. The catalytic properties of 1 and the amides are probed in enanatioselective rhodium-catalysed hydrogenation and palladium-catalysed asymmetric allylic alkylation. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    A Trinuclear Aqua Cyano-Bridged Ruthenium Complex [{(,5 -C5H5)(PPh3)2Ru(,-CN)}2RuCl2(PPh3)(H2O)]PF6: Synthesis, Characterization and Crystal Structure

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2007
    Viatcheslav Vertlib
    Abstract The organometallic trinuclear aqua cyano-bridged complex [{(,5 -C5H5)(PPh3)2Ru(,-CN)}2RuCl2(PPh3)(H2O)]PF6 (1), in which the fragment [RuCl2(PPh3)(H2O)] acts as a bridge and an acceptor group between the two terminal cyclopentadienyl ruthenium cyano moieties, was isolated in moderate yield from the reaction of [(,5 -C5H5)(PPh3)2RuCN] with [RuCl2(PPh3)3] in THF. To the best of our knowledge, compound 1 is one of the few examples of a trinuclear array of ruthenium fragments bridged by the nitrogen atom of the,C,N, group (Ru,C,N,Ru,,N,C,Ru) with a Ru-coordinated water molecule. The new aqua complex was structurally characterized by FTIR, 1H, 13C, and 31P NMR spectroscopy, mass spectrometry, elemental analysis, single-crystal X-ray diffraction, and cyclic voltammetry. The title complex crystallizes in a triclinic unit cell a = 17.3477(6) Å, b = 17.8551(5) Å, c = 18.2460(7) Å, , = 95.693(2)°, , = 111.648(2)°, and , = 97.839(2)° in the space group P with Z = 2.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


    Unusual T4(1) Water Chain Stabilized in the One-Dimensional Chains of a Copper(II) Coordination Polymer

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2007
    Yi Jin
    Abstract A novel T4(1) water chain in a new CuII coordination polymer, {[Cu(C4H6N2)2(C4H2O4)] (H2O)3}n (1, where C4H6N2 = 2-methylimidazole, C4H2O4 = maleate), has been synthesized and structurally characterized by single-crystal X-ray diffraction. Thermogravimetry, infrared spectroscopy, elemental analysis, and magnetic analysis have also been used to characterize 1. Complex 1 crystallizes in the trigonal space group P3221, and the 1-D chains composed of cyclic water tetramers play an important role in stabilizing the overall polymeric structure. Furthermore, this 1-D water chain presents an unusual association mode of water molecules.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]