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  • 1
    ISSN: 1434-1948
    Keywords: Hydrogen bonds ; Indium ; Lithium ; Nitrogen heterocycles ; Zinc ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The lithiation of 2,5-di(tert-butyl)pyrrole (1) yields bis(tetrahydrofuran)lithium 2,5-di(tert-butyl)pyrrolide (2), which is monomeric in solution as well as in the solid state. Due to the coordination number of three for the lithium atom, short Li-O and Li-N bond lengths of 193 pm are observed. The metathesis reaction of 2 with tris(trimethylsilyl)-methylzinc chloride (3) gives colorless bis[tris(trimethyl-silyl)methylzinc] chloride 2,5-di(tert-butyl)pyrrolide (4). The pyrrolide ligand and the chlorine atom bridge the zinc atoms. One of the zinc atoms is bonded to the nitrogen atom of the pyrrolide substituent, while the other bonds to the opposite C-C bond. At 215 pm, the Zn-N bond is very long compared to those in alkylzinc amides, whereas the Zn-C distances lie in the range of Zn-C bond lengths found between zinc and η5-bonded cyclopentadienide ligands. The molecular structures of 1 and of the low-melting THF adduct 1·thf show a similar 2,5-di(tert-butyl)pyrrole molecule, but in the latter case a weak N-H···O bond is observed (N-H 97 pm, O···H 199 pm).
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0044-2313
    Keywords: Yttrium complexes ; yttrium tris[bis(trimethylsilyl)amide] ; yttrium tris[bis(trimethylsilyl)methanide] ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bis(trimethylsilyl)amides and -methanides of Yttrium  -  Molecular Structures of Tris(diethylether-O)lithium-(μ-chloro)-tris[bis(trimethylsilyl)methyl]yttriate, solvent-free Yttrium Tris[bis(trimethylsilyl)amide] as well as the Bis(benzonitrile) ComplexThe reaction of yttrium(III) chloride with the three-fold molar amount of LiE(SiMe3)2 (E = N, CH) yields the corresponding yttrium derivatives. Yttrium tris-[bis(trimethylsilyl)amide] crystallizes in the space group P31c with a = 1 636,3(2), c = 849,3(2) pm, Z = 2. The yttrium atom is surrounded trigonal pyramidal by three nitrogen atoms with Y—N-bond lengths of 222 pm. Benzene molecules are incorporated parallel to the c-axes. The compound with E = CH crystallizes as a (Et2O)3LiCl-adduct in the monoclinic space group P21/n with a = 1 111,8(2), b = 1 865,2(6), c = 2 598,3(9) pm, β = 97,41(3)° and Z = 4. The reaction of yttrium tris[bis(trimethylsilyl)amide] with benzonitrile yields the bis(benzonitrile) complex, which crystallizes in the triclinic space group P1 with a = 1 173,7(2), b = 1 210,3(2), c = 1 912,4(3) pm, α = 94,37(1), β = 103,39(1), γ = 117,24(1)° and Z = 2. The amido ligands are in equatorial, the benzonitrile molecules in axial positions.
    Notes: Die Reaktion von Yttrium(III)-chlorid mit der dreifachen molaren Menge LiE(SiMe3)2 (E = N, CH) ergibt die entsprechenden Yttrium-Derivate. Yttrium-tris[bis(trimethylsilyl)amid] kristallisiert in der Raumgruppe P31c mit a = 1 636,3(2), c = 849,3(2) pm, Z = 2. Das Yttriumatom ist trigonal pyramidal koordiniert mit Y—N-Bindungslängen von 222 pm. Entlang der c-Achse sind Benzolmoleküle eingeschlossen. Die Verbindung mit E = CH kristallisiert als (Et2O)3LiCl-Addukt in der monoklinen Raumgruppe P21/n mit a = 1 111,8(2), b = 1 865,2(6), c = 2598,3(9) pm, β = 97,41(3)° und Z = 4. Die Umsetzung von Yttrium-tris[bis(trimethylsilyl)amid] mit Benzonitril ergibt einen Bis(benzonitril)-Komplex, der in der triklinen Raumgruppe P1 mit a = 1173,7(2), b = 1210,3(2), c = 1912,4(3) pm, α = 94,37(1), β = 103,39(1), γ = 117,24(1)° und Z = 2 kristallisiert. Die Amido-Liganden sind äquatorial, die Benzonitril-Moleküle axial koordiniert.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1555-1560 
    ISSN: 0044-2313
    Keywords: Iodocuprate(I) ; [Cu2I4]2- ; tetraphenylphosphonium ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zwei neue Modifikationen von [P(C6H5)4]2[Cu2I4]Bei der Reaktion von granuliertem Kupfer mit Iod und [P(C6H5)4]I in trockenem Aceton unter Stickstoffatmosphäre wurden Einkristalle von zwei neuen Modifikationen von [P(C6H5)4]2[Cu2I4] erhalten. Sie kristallisieren monoklin, Raumgruppe P21/n (Nr. 14), a = 11.550(6), b = 7.236 (2), c = 27.232 (13) Å, β = 98.13(3)°, V = 2253(2) Å3 und Z = 2 ([P(C6H5)4]2[Cu2I4]-C) bzw. Raumgruppe Cc (Nr. 9), a = 17.133(5), b = 15.941(5), c = 18.762(6) Å, β = 114.02(1)°, V = 4681(3) Å3 und Z = 4 ([P(C6H5)4]2[Cu2I4] -D). In diesen Verbindungen liegen dimere di-μ-iodo-diiodocuprat(I)-Einheiten vor, die planar (C) bzw. gewinkelt (D) sind.
    Notes: Single crystals of two new modifications of [P(C6H5)4]2[Cu2I4] were obtained by reaction of granulated copper with iodine and [P(C6H5)4]I in dry acetone under nitrogen atmosphere. They crystallise monoclinically, space group P21/n (No. 14), a = 11.550(6), b = 7.236(2), c = 27.232(13) Å, β = 98.13(3)°, V = 2253(2) Å3, and Z = 2 ([P(C6H5)4]2[Cu2I4]-C), and space group Cc (No. 9), a = 17.133(5), b = 15.941(5), c = 18.762 (6) Å, β = 114.02(1)°, V = 4681(3) Å3, and Z = 4 ([P(C6H5)4]2[Cu2I4]-D), respectively. In these compounds the [CuI2]- anions form dimers di-μ-iodo-diiodocuprate(I), which are either planar (C) or folded (D).
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 685-688 
    ISSN: 0044-2313
    Keywords: Copper antimony selenide ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structure of Cu3SbSe3The hitherto unknown crystal structure of Cu3SbSe3 has been determined from single crystals. The compound crystallizes in the orthorhombic system, space group Pnma (No. 62), with a = 7.9865(8), b = 10.6138(9) and c = 6.8372(7) Å, V = 579.6(1) Å3, Z = 4. Most remarkable feature of the structure are groups of three cis-edge-sharing tetrahedra [Cu3Se8] which are interlinked to a threedimensional arrangement by SbSe3-units. In contrast to Cu3SbS3 in the temperature range from -180 to 25°C no hints for a phase transition could be detected by means of X-ray- and thermoanalytical methods.
    Notes: Die bisher unbekannte Kristallstruktur von Cu3SbSe3 wurde aus Einkristalldaten ermittelt. Die Verbindung kristallisiert orthorhombisch, RG Pnma (Nr. 62) mit a = 7,9865(8), b = 10,6138(9) und c = 6,8372(7) Å, V = 579.6(1) Å3, Z = 4. Die Struktur zeichnet sich durch Baugruppen [Cu3Se8] aus drei cis-kantenverknüpften Tetraedern aus, die über ihre Liganden mit SbSe3-Gruppen zu einem dreidimensionalen Netzwerk verknüpft sind. Im Gegensatz zu Cu3SbS3 konnten Hinweise auf eine Phasenumwandlung im Temperaturbereich von -180 bis 25°C weder durch röntgenographische noch durch thermoanalytische Untersuchungen gefunden werden.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1992-1997 
    ISSN: 0044-2313
    Keywords: Copper antimony sulfide ; sulfo salts ; crystal structure ; phase transitions ; Extended Hückel calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cu3SbS3: Crystal Structure and PolymorphismThe hitherto unknown crystal structure of β-Cu3SbS3 at room temperature could be determined from a twinned crystal. The compound crystallizes in the monoclinic system, space group P21/c (No. 14), with a = 7.808(1), b = 10.233(2) and c = 13.268(2) Å, β = 90.31(1)°, V = 1 060.1(2) Å3, Z = 8. An Extended-Hückel-Calculation shows weak bonding interactions between copper atoms which are coordinated trigonal planar. At -9°C a first order phase transition occurs and the crystals disintegrate. The low-temperature modification (γ) crystallizes in the orthorhombic system with a = 7.884(2), b = 10.219(2) and c = 6.623(2) Å, V = 533.6(2) Å3 (-100°C). At 121°C a phase transition of higher order is observed. The high-temperature polymorph (α) of Cu3SbS3 is orthorhombic again. From high-temperature precession photographs the space groups Pnma (No. 62) or Pna21 (No. 33) can be derived. The lattice constants at 200°C are a = 7.828(3), b = 10.276(4) and c = 6.604(3) Å, V = 531.2(2) Å3.
    Notes: Die bisher unbekannte Kristallstruktur von β-Cu3SbS3 bei Zimmertemperatur wurde anhand eines verzwillingten Kristalls ermittelt. Die Verbindung kristallisiert monoklin, RG P21/c (Nr. 14) mit a = 7,808(1), b = 10,233(2) und c = 13,268(2) Å, β = 90,31(1)°, V = 1 060,1(2) Å3, Z = 8. Eine Extended-Hückel-Rechnung ergibt schwach bindende Wechselwirkungen zwischen den trigonal-planar koordinierten Kupferatomen. Bei -9°C erfolgt eine reversible Phasenumwandlung 1. Ordnung, bei der die Kristalle zerfallen. Die Tieftemperaturmodifikation (γ) kristallisiert orthorhombisch mit a = 7,884(2), b = 10,219(2) und c = 6,623(2) Å, V = 533,6(2) Å3 (-100°C). Beim Aufheizen beobachtet man bei 121°C eine Phasenumwandlung höherer Ordnung. Die Hochtemperaturmodifikation (α) von Cu3SbS3 kristallisiert ebenfalls orthorhombisch. Aus Hochtemperatur-Präzessionsaufnahmen ergibt sich Pnma (Nr. 62) oder Pna21 (Nr. 33) als mögliche Raumgruppe. Die Gitterkonstanten bei 200°C sind nach Guinier-Aufnahmen a = 7,828(3), b = 10,276(4) und c = 6,604(3) Å, V = 531,2(2) Å3.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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