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  • 1
    Electronic Resource
    Electronic Resource
    Ultrasonic activation of chalcogen-chalcogen bonds: synthesis of bis(organyltellurenyl) selenides and sulfides, (RTe)2(Se,S) (1991)
    s.l. : American Chemical Society
    Organometallics 10 (1991), S. 2101-2102 
    Details
    ISSN: 1520-6041
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/om00053a008
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  • 2
    Electronic Resource
    Electronic Resource
    Darstellung und Eigenschaften von TiCl4-n(OTeF5)n(n = 1-4), Cs2[Ti(OTeF5)6] und Ti(OTeF5)4 · 2 POCl3 (1980)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 1414-1419 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Properties of TiCl4-n(OTeF5)n(n = 1-4), Cs2[Ti(OTeF5)6] und Ti(OTeF5)4 · 2 POCl3TiCl4 reacts with HOTeF5 to afford TiCl3OTeF5. This compound dismutates via TiCl2 (OTeF5)2 and TiCl(OTeF5)3 to Ti(OTeF5)4. With CsOTeF5 the latter forms Cs2[Ti(OTeF5)6] but not Cs[Ti(OTeF5)5]. Ti(OTeF5)4 shows strong Lewis acid behavior. Interaction with POCl3, (CH3)2SO, CH3CN, CH3O[CH2]2OCH3, and CH3NO2 was studied and a correlation of 19F NMR data of the F5TeO group with the donor numbers of the mentioned bases was undertaken.
    Notes: TiCl4 reagiert mit HOTeF5 unter Bildung von TiCl3OTeF5, das über TiCl2 (OTeF5)2 und TiCl(OTeF5)3 zu Ti(OTeF5)4 dismutiert. CsOTeF5 bildet mit dieser Verbindung Cs2[Ti(OTeF5)6], jedoch nicht Cs[Ti(OTeF5)5]. Die Adduktbildung von Ti(OTeF5)4 mit POCl3, (CH3)2SO, CH3CN, CH3O[CH2]2OCH3 und CH3NO2 wurde untersucht und eine Korrelation zwischen 19F-NMR-Daten der F5TeO-Gruppe mit den Donorzahlen der Basen versucht.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19801130420
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  • 3
    Electronic Resource
    Electronic Resource
    Darstellung und Eigenschaften von B(OTeF5)3, Cs[B(OTeF5)4] und B(OTeF5)3 · CH3CN (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 2644-2648 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preparation and Properties of B(OTeF5)3, Cs[B(OTeF5)4], and B(OTeF5)3·CH3CNInteraction of BCl3 with HOTeF5 affords B(OTeF5)3 (1) in quantitative yield. This compound reacts with CsOTeF5 to give Cs[B(OTeF5)4] (2) and with acetonitrile to form the adduct B(OTeF5)3·CH3CN (3). Thermolysis of 1 above 130°C leads to TeOF4 which cannot be isolated, but dimerizes to 4 and polymerizes to F5Te[OTeF4]nOTeF5.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811140727
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  • 4
    Electronic Resource
    Electronic Resource
    Darstellung und Eigenschaften von cis- und trans-(HO)2TeF4 (1982)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 1019-1027 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Properties of cis- and trans-(HO)2TeF4Hydrolysis of imidazolium pentafluoroorthotellurate affords diimidazolium cis-tetrafluoroorthotellurate (1b), solvolysis of orthotelluric acid in HF/pyridine yields monopyridinium trans-tetrafluoroorthotellurate (2a). From these salts the free acids cis- and trans-(HO)2TeF4 (1, 2) are liberated with conc. sulfuric acid. 2 is thermodynamically more stable than 1, isomerization proceeds only beyond 150°C. 2 hydrolyzes within minutes, whereas 1 is stable enough in aqueous solution to allow the determination of the acidity constants: pK1 = 0.68, pK2 = 4.99. In absol. methanol 1 is a somewhat stronger acid than 2. Both acids form volatile hydrates, 1:1 adducts with dioxane, and with SO3 cis- and trans-HOTeF4(OSO3H) (1c, 2c) and cis- and trans-TeF4(OSO3H) (1d, 2d).
    Notes: Hydrolyse von Imidazolium-pentafluoroorthotellurat führt zu Diimidazolium-cis-tetrafluoroorthotellurat (1b), Solvolyse von Orthotellursäure in HF/Pyridin zu Monopyridinium-trans-tetrafluoroorthotellurat (2a). Aus diesen Salzen werden mit konz. Schwefelsäure cis- und trans-(HO)2TeF4 (1, 2) freigesetzt. 2 ist thermodynamisch stabiler als 1, Isomerisierung tritt jedoch erst oberhalb 150°C ein. 2 hydrolysiert innerhalb von Minuten, die Stabilität von 1 in wäßriger Lösung erlaubt die Bestimmung der Säureexponenten: pK1 = 0.68, pK2 = 4.99. In absol. Methanol ist 2 eine etwas schwächere Säure als 1. Beide Säuren bilden sublimierbare Hydrate, 1:1-Addukte mit Dioxan und mit SO3 die Verbindungen cis- und trans-HOTeF4(OSO3H) (1c, 2c) und cis- und trans-TeF4(OSO3H)2 (1d, 2d).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19821150318
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  • 5
    Electronic Resource
    Electronic Resource
    Cyclopentadienone Cyclopentadienediyl Diselenoketals (1998)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1998 (1998), S. 973-976 
    Details
    ISSN: 1434-1948
    Keywords: Cyclopentadiene ; Selenium ; Ketal ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of di-tert-butylcyclopentadiene with excess potassium tert-butoxide in the presence of elemental selenium leads to cyclopentadienes bridged by two or three selenium atoms through one or two diselenoketal functionalities. 2,5,4′,6′-Tetra-tert-butyl-5′H-spirocyclopentane-1,2′-cyclopenta[b][1,3]diselena-2,4-diene (1) and 1,3,5,7-tetra-tert-butyl-3a,7a-dihydro-3a,7a-epi-selenodicyclopenta[b,e][1,4]diselenine (2) have been characterized by single-crystal X-ray diffraction.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Stabile Tellur-Ylide: Darstellung und Reaktivität von Diorganyltelluronium-4,5-dicyanimidazol-2-yliden (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 699-705 
    Details
    ISSN: 0009-2940
    Keywords: Tellurium ylides ; Diorganyltelluronium 4,5-dicyanoimidazole-2-ylides, stability of, reactivity of, Stevens rearrangement ; Imidazole, 2-(methyltelluro)- ; Imidazolide, 2-(methyltelluronio)- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Stable Tellurium Ylides: Synthesis and Reactivity of Diorganyltelluronium 4,5-Dicyanoimidazol-2-ylidesDiorganyl tellurides R2Te (R=Me, Me3SiCH2, Ph) react with 2-diazo-4,5-dicyano-2H-imidazole (1) at - 30°C to form the title compounds 2 - 4. The ylides 3 and 4 are thermally stable up to their melting points of 159 and 243°C, resp., whereas 2 undergoes a modified Stevens rearrangement at 190°C with formation of a 2-(methyltelluro)imidazole (10). The reactivity of 2 - 4 is determined by an extreme charge separation between the onium centre and the ylide entity. No Wittig reactivity is observed, alkylation occurs at the imidazole nitrogen and carbanions lead to tetraorganyl tellurium compounds with limited stability.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240405
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  • 7
    Electronic Resource
    Electronic Resource
    Synthesis and Structure of Bis(2,4-di-tert-butyl-1,3-cyclopentadien-1-yl)-disulfane, S2(tBu2C5H3)2, and Bis[2,4-di-tert-butyl-5-(trimethylsilyl)-1,3-cyclopentadien-1-yl]disulfane, S2 [tBu2(Me3Si)C5H2]2 (1996)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 129 (1996), S. 69-71 
    Details
    ISSN: 0009-2940
    Keywords: Disulfanes ; Cyclopentadienyl ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of 1,3-di-tert-butylcyclopentadienyllithium and 1,3-di-tert-butyl-4-(trimethylsilyl)cyclopentadienyllithium with S2Cl2 gives bis(2,4-di-tert-butyl-1,3-cyclopentadien-1-yl)di-sulfane (1) and bis[2,4-di-tert-butyl-5-(trimethylsilyl)-1,3-cyclopentadien-1-yl) disulfane (2), respectively. The structure of 2 was determined by single-crystal X-ray diffraction. Compounds 1 and 2 are the first biscyclopentadienylchalcogens with the chalcogen in vinylic position.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19961290114
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  • 8
    Electronic Resource
    Electronic Resource
    Lithium 2,2,6,6-Tetramethylpiperidinoselenolate: An Unsymmetrical Dimer with an Unusually Coordinated Lithium (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 119-122 
    Details
    ISSN: 0009-2940
    Keywords: Selenolate ; Aminoselenolate ; Lithium compound i Ab initio calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lithium 2,2,6,6-tetramethylpiperidide inserts elemental selenium into its Li-N bond with the formation of lithium 2,2,6,6-tetramethylpiperidinoselenolate 1. In the crystal 1 is an unsymmetric dimer. One lithium atom is coordinated tetrahedrally by two molecules of tetrahydrofuran and two selenium atoms, the other lithium atom exhibits an approximately rectangular-planar coordination by two N,Se-chelating groups. The lithium atoms are bridged by two selenium atoms thus forming a planar Li2Se2 core. Ab initio Hartree-Fock calculations show 1 and the hypothetical symmetric dimer 2 to be of equal energy, whereas the non-chelated dimer 3 is of distinctly higher energy. Exclusive crystallization of 1 is most likely a consequence of its large dipole moment of 6.18 D. Calculations also show that the deformation of the observed geometry around the uniquely coordinated lithium atom in 1 towards distorted tetrahedral or complete planarity leads to an increase of energy. Excessive charge transfer from selenium to nitrogen explains the overwhelming tendency for the N,Se-chelating bonding.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300120
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  • 9
    Electronic Resource
    Electronic Resource
    SET-Mechanismus bei Substitutionsreaktionen an Diorganyldichalkogeniden (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2279-2281 
    Details
    ISSN: 0009-2940
    Keywords: SET mechanism ; Selenide, tris(trimethylsilyl)methyl-substituted ; Telluride, tris(trimethylsilyl)methyl-substituted ; Selenol, tris(trimethylsilyl)methyl- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: SET Mechanism in Substitution Reactions with Diorganyl DichalcogenidesReaction of the sterically demanding tris(trimethylsilyl)methyl carbanion (Tsi⊖) with bis[tris(trimethylsilyl)methyl] diselenide (Tsi2Se2) or ditelluride (Tsi2Te2) in THF does not lead to the expected substitution products Tsi2Se or Tsi2Te. Instead, 2- tetrahydrofuranyl tris(trimethylsilyl)methyl selenide (4a) or telluride (4b), tris(trimethylsilyl)methane (5), and tris(trimethylsilyl)-methylselenol (6a) are formed. This is interpreted in terms of a single electron transfer (SET) from Tsi⊖ to the respective diorganyl dichalcogenide, giving rise to intermediate chalcogenyl radicals TsiSe⊙ and TsiTe⊙, which are trapped by the solvent THF. Methyl- or phenyllithium react with Tsi2Se2 or Tsi2Te2 to afford the expected substitution products Me—Ch—Tsi (1a,1b) or Ph—Ch—Tsi (2a, 2b) (a: CH = Se, b: Ch = Te), but Products derived from chalcogenyl radicals are detectable in minor yields.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221213
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  • 10
    Electronic Resource
    Electronic Resource
    Tris(trimethylsilyl)methantellurenylhalogenide (Me3Si)3CTeX (X = Cl, Br, I): Synthese stabiler Alkantellurenylhalogenide (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1255-1256 
    Details
    ISSN: 0009-2940
    Keywords: Alkanetellurenyl halides ; Tris(trimethylsilyl)methanetellurenyl halides ; Methyl tris(trimethylsilyl)methyl telluride ; Phenyl tris(trimethylsilyl)methyl telluride ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tris (trimethylsilyl)methanetellurenyl Halides (Me3Si)3 CTex (X = Cl, Br, I): Synthesis of Stable Alkanetellurenyl HalidesThe first stable and isolable alkanetellurenyl halides, tris(trimethylsilyl)methanetellurenyl chloride, bromide, and iodide (1a-c) are obtained quantitatively by halogenolysis of bis[tris-(trimethylsilyl)methyl] ditelluride with SO2Cl2, Br2, and I2, respectively. Their synthetic potential is examplified by transformation to methyl tris(trimethylsilyl)methyl telluride (2) and phenyl tris(trimethylsilyl)methyl telluride (3).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220707
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