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Now showing 1 - 10 of 21
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    Dicyclohexylbis(naphthalen-1-ylmethyl)phosphonium chloride chloroform disolvate
    (Chester : International Union of Crystallography, 2012) Gowrisankar, S.; Neumann, H.; Spannenberg, A.; Beller, M.
    In the title solvated phosphonium salt, C34H40P+·Cl -·2CHCl3, the two cyclohexyl and two 1-naphthylmethyl groups at the P atom are in a distorted tetrahedral arrangement [105.26 (6)-113.35 (6)°]. Both cyclohexyl rings adopt a chair conformation. The dihedral angle between the naphthyl ring systems is 74.08 (3)°.
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    Dicarbonyl-{3,3′-di-tert-butyl-5,5′-di-methoxy-2, 2′-bis[(4,4,5,5-tetraphenyl-1,3,2-dioxaphospho-lan-2-yl)-oxy-κP] biphen-yl}hydridorhodium(I) diethyl ether monosolvate
    (Chester : International Union of Crystallography, 2012) Selent, D.; Spannenberg, A.; Börner, A.
    In the title compound, [Rh(C 74H 68O 8P2)H(CO) 2]·C 4H 10O, the C 2HP 2 coordination set at the Rh I ion is arranged in a distorted trigonal-planar geometry with one P atom of the diphosphite mol-ecule and the H atom adopting the axial coordination sites.
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    2,4-Bis(diphenyl-phosphan-yl)-1,1,2,3,3,4-hexa-phenyl-1,3-diphospha-2, 4-dibora-cyclo-butane tetra-hydro-furan sesqui-solvate
    (Chester : International Union of Crystallography, 2012) Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    In the title compound, C60H50B2P 4·1.5C4H8O, the diphospha-diborane mol-ecule lies on an inversion centre, whereas the disordered tetra-hydro-furan solvent mol-ecule is in a general position with a partial occupancy of 0.75. The diphosphadiborane mol-ecule consists of an ideal planar four-membered B 2P2 ring with an additional phenyl and a-PPH2 group attached to each B atom.
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    Di-μ-sulfido-bis{[rac-1,2-bis(η5-4,5,6, 7-tetrahydroinden-1-yl)ethane]zirconium(IV)} toluene monosolvate
    (Chester : International Union of Crystallography, 2012) Haehnel, M.; Altenburger, K.; Spannenberg, A.; Arndt, P.; Rosenthal, U.
    The title dimeric zirconium complex, [Zr3(C20H 24)2S2]·C7H8, was obtained from the reaction of (ebthi)Zr(η2-Me3Si-C2-SiMe3) [ebthi is rac-1,2-bis(η5-4,5,6,7-tetrahydroinden-1-yl)ethane] and S=C=N-ada (ada = adamantan-1-yl) along with the formation of the isonitrile C N-ada. Each ZrIV atom is coordinated by the sterically hindered ebthi ligand and two μ-sulfide ligands in a strongly distorted tetrahedral geometry. The [ZrS]2 unit is almost planar (mean deviation from the best plane of the four atoms = 0.025Å). A -CH2-CH2- group in one ebthi ligand was disordered over two sites, with refined occupancy factors of 0.551(6) and 0.449(6). The asymmetric unit also contains a toluene solvent molecule.
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    Tetracarbonyl[bis(diphenylphosphanyl)-tetramethyldisiloxane- κ 2 P,P′]chromium(0)
    (Chester : International Union of Crystallography, 2012) Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, [Cr(C 28H 32OP 2Si 2)(CO) 4], was obtained by the ligand-exchange reaction of Cr(CO) 6 with (Ph 2PSiMe 2) 2O in refluxing toluene. The CrC 4P 2 coordination geometry is distorted octa-hedral, with a P - Cr - P bite angle of 99.22 (4)°.
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    (+)-Chlorido[(1,2,3,4-η;P 2′)-2′- diphenylphosphanyl-2-diphenylphosphoryl-1,1′-binaphthyl]rhodium(I) methanol monosolvate
    (Chester : International Union of Crystallography, 2012) Meissner, A.; Selle, C.; Drexler, H.-J.; Heller, D.
    In the title complex, [RhCl(C 44H 32OP 2)]·CH 3OH, the Rh I ion is coordinated by a naphthyl group of a partially oxidized 2,2′-bis-(diphenylphosphanyl)-1, 1′-binaphthyl (BINAP) ligand in a 4 mode, one P atom of the diphenylphosphanyl group and one Cl atom. The P=O group does not interact with the Rh I ion but accepts an O - H⋯O hydrogen bond from the methanol solvent molecule.
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    Synthetic glycopeptides and glycoproteins with applications in biological research
    (Frankfurt am Main : Beilstein-Institut, 2012) Westerlind, Ulrika
    Over the past few years, synthetic methods for the preparation of complex glycopeptides have been drastically improved. The need for homogenous glycopeptides and glycoproteins with defined chemical structures to study diverse biological phenomena further enhances the development of methodologies. Selected recent advances in synthesis and applications, in which glycopeptides or glycoproteins serve as tools for biological studies, are reviewed. The importance of specific antibodies directed to the glycan part, as well as the peptide backbone has been realized during the development of synthetic glycopeptide-based anti-tumor vaccines. The fine-tuning of native chemical ligation (NCL), expressed protein ligation (EPL), and chemoenzymatic glycosylation techniques have all together enabled the synthesis of functional glycoproteins. The synthesis of structurally defined, complex glycopeptides or glyco-clusters presented on natural peptide backbones, or mimics thereof, offer further possibilities to study protein-binding events.
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    The molecular structure of 1,2:5,6-Di-O-isopropylidene-3-otoluenesulfonyl- α-D-glucofuranose
    (Basel : MDPI AG, 2012) Mamat, C.; Peppel, T.; Köckerling, M.
    The crystal and molecular structure of 1,2:5,6-di-O-isopropylidene-3-Otoluenesulfonyl- α-D-glucofuranose is reported. This compound crystallizes from a petroleum ether/ethyl acetate mixture with the chiral orthorhombic space group P212121 with four molecules in the unit cell. The unit cell parameters are: a = 9.7945(7) Å, b = 10.1945(7) Å, c = 21.306(1) Å, and V = 2127.4(2) Å3. No classical hydrogen bonds were found. Bond lengths and angles of this tosylated glucofuranose derivative are typical.
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    Comment on "Synthesis, characterization and growth mechanism of flower-like vanadium carbide hierarchical nanocrystals"
    (Cambridge : Royal Society of Chemistry, 2012) Presser, Volker; Vakifahmetoglu, Cekdar
    This Letter is in response to a recent paper by Ma et al. (CrystEngComm, 2010, 12, 750-754) which arguably studied vanadium carbide nanostructures whereas all available evidence indicates the study of vanadium oxide. We feel that it is important to communicate to the community several inconsistencies so that the interesting material reported can be seen in the right light, especially with several groups nowadays having reported similar structures from vanadium oxide synthesis.
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    Bi-phasic nanostructures for functional applications
    (Cambridge : Royal Society of Chemistry, 2012) Veith, Michael; Lee, Juseok; Miro, Marina Martinez; Akkan, C. Kaan; Dufloux, Cecile; Aktas, O. Cenk
    Biphasic solid state composites of the type metal/metal oxide or element/element oxide can be synthesized in one pot chemical reactions using so called molecular "single source precursors". Due to their singular genesis these composites show peculiar hetero-structures based on core-shell hierarchies such as superlattices and composite nanospheres or nanowires. They exhibit superior or new functional properties compared to their individual constituent compounds. In the current work, we review in particular the synthetical and mechanistical approach of bi-phasic (Al/Al2O3) nanostructures such as nanospheres, nanowires and nanoloops using a single source precursor. Other bi-phasic materials of the general formula M/MOx (for example M = Ge, Sn, Pb) are addressed for comparison. The impact of different synthetical conditions as well as of modification of surfaces by laser techniques and their technological relevance are presented briefly. Additionally, functional applications of the prepared surfaces are explained with some outstanding case studies. These case studies are primarily concerned with their use as biomaterials and their application in medicine as well as with their use as thin films for optics and functional surfaces.