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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 109 (1976), S. 761-768 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal and Molecular Structure of Bis(di-tert-butylmethyl) OxalateThe structure of the title compound (4) has been determined from X-ray data and refined to R = 0.048. 4 crystallizes in the space group C2/c with lattice parameters a = 23.599(4) Å, b = 12827(1) Å, C = 15.272(2) Å and β = 108.89(2)°. - The molecule exhibits the unusual Z-configuration. Bond lenghts and angles show no particularities with the exception of the central C—C-bond which appears significantly short (a = 1.531 Å).
    Notes: Die Struktur der Titelsubstanz (4) wurde röntgenorgraphisch bestimmt und bis zu einem R von 0.048 verfeinert. 4 kristallisiert in der Raumgruppe C2/c mit den Zellparametern a = 23.599(4) Å, b = 12.827 (1) Å, c = 15.272(2) Å und β = 108.89(2)°. - Das Molekül liegt in der ungewöhnlichen Z-Konfiguration vor. Bindungslängen und -winkel zeigen mit Ausnahme der zentralen C—C-Bindung, die mit A = 1.531 Å relativ kurz erscheint, normale Werte.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 1159-1166 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Twisted Oxalic Acid Derivatives The Crystal and Molecular Structure of N,N,N′,N′-Tetramethyloxamide and -monothiooxamideThe structures of the title compounds (2 and 3) have been determined from X-ray data, and refined to R = 0.065 (2) and 0.057 (3) respectively. 2 crystallizes in the space group C2/c, 3 in the space group P21/c. - In the crystal 2 exhibits a configuration in which the two halves of the molecule are twisted by 71.4°. This angle amounts to 87.4° in 3.
    Notes: Die Strukturen der Titelsubstanzen (2 und 3) wurden röntgenographisch bestimmt und bis zu R-Werten von 0.065 (2) bzw. 0.057 (3) verfeinert. 2 kristallisiert in der Raumgruppe C2/c, 3 in der Raumgruppe P21/c. - 2 liegt im Kristall in einer Konfiguration vor, bei der die beiden Molekülhälften um 71.4° gegeneinander verdrillt sind; bei 3 beträgt dieser Winkel 87.4°.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 1511-1517 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Alkynul Compounds of Transition Metals, XXIX. Alkynyl[ethylenebis(diphenylphosphine)] complexes of Platinum(II)cis-[PtCl2(dpe)] reacts with alkali acetylides in liquid ammonia or liquid methylamine to yield nonionic monomers of the type cis-[Pt(C≡C̊)2(dpe)] (dpe = (C6H5)2P[CH2]2P(C6H5)2; R = H, CH3, C6H5). The analogous reaction with the divalent anion of o-diethynylbenzene, however, gives the polymeric cis-[Pt(C≡C)2C6H4(dpe)]n, cis-[Pt(C≡C)2C6H4(dpe)]n. With an excess of acetylide polymeric complexes of the type [K2Pt(C≡C̊)4(dpe)]n are precipitated.
    Notes: Durch Umsetzung von cis-[PtCl2(dpe)] mit Alkaliacetyliden in flüssigem Ammoniak bzw.flüssigem Methylamin werden nichtionische, einkernige Verbindungen des Typs cis-[Pt(C≡C̊)2(dpe)] (dpe = (C6H5)2P[CH2]2P(C6H5)2; R = H, CH3, C6H5) dargestellt. Eine analoge Reaktion mit dem zweiwertigen Anion des o-Diäthinylbenzols hingegen führt zu einem koordinationspolymeren cis-[Pt(C≡C)2C6H4(dpe)]n. Die Anwendung eines Acetylidüberschusses führt zu polymeren Komplexen des Typs [K2Pt(C≡C̊)4(dpe)]n.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 3792-3798 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal and Molecular Structure of O,O′-Diethyl 5-tert-ButyldithioisophthalateThe structure of the title compound (4) has been determined from X-ray data by means of direct methods and refined to R=0.057. 4 crystallizes in the space group P1¯.  -  The molecule is approximately planar; the interplanar angles between the plane of the benzene ring and those of the RO—CS-groups being 5.3° and 7.6°, respectively. The C=S bond length of 1.631 ± 0.002 Å points to a moderate double bond character.
    Notes: Die Struktur der Titelsubstanz (4) wurde röntgenographisch mit Hilfe der Direktmethode bestimmt und bis zu einem R von 0.057 verfeinert. 4 kristallisiert in der Raumgruppe P1¯.  -  Das Molekül ist fast eben gebaut; die Interplanarwinkel zwischen der Ebene des Benzolrings und denen der RO—CS-Gruppen betragen 5.3° und 7.6°. Die C=S-Bindungslänge von 1.631 ± 0.002 Å läßt auf einen mäßig ausgeprägten Doppelbindungscharakter schließen.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 1685-1692 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation, Reactions, Crystal and Molecular Structure of the Cyclic Sulfenylcarboxylate: Methyl 3-Oxo-3H-2.1-benzoxathiole-7-carboxylateOn heating of 2-(benzylsulfinyl)isophthalic acid (4) with acetic acid/acetic anhydride the cyclic sulfenylcarboxylates 7a and 7b are formed in an unexpected elimination reaction and rearrangement, respectively. 7a can be methylated to the title compound 7c. The structure of 7c has been determined from X-ray data and refined to R = 0.06. 7c crystallizes in the monoclinic system, space group P21/c. The molecule is nearly planar and reveals an intramolecular interaction which is reflected in a short S…‥O distance of 252 pm and an unusual IR spectrum (νCO 1750. 1650 cm-1).
    Notes: In einer unerwarteten Eliminierungsreaktion bzw. Umlagerung bilden sich beim Erhitzen von 2-(Benzylsulfinyl)isophthalsäure (4) mit Essigsäure/Essigsäureanhydrid die cyclischen Carbonsäure-Sulfensäureanhydride 7a und 7b. 7a kann zur Titelverbindung 7c methyliert werden. Die Struktur von 7c wurde röntgenographisch bestimmt und bis zu R = 0.06 verfeinert. 7c kristallisiert monoklin in der Raumgruppe P21/c. Das Molekül ist fast planar und zeigt intramolekulare Wechselwirkung, die an einem geringen S…‥O-Abstand (252 pm) und einem ungewöhnlichen IR-Spektrum (νCO 1750, 1650 cm-1) erkannt werden kann.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 2255-2277 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thioketyls, 5. Isotropic ESR Parameters in Thio- and SelenoketylsThe preparation of aliphatic and aromatic thio- and selenoketones and of some of their D-, 13C-, and 77Se derivatives is described. Most of these compounds yield persistent radical anions on one-electron electroreduction, which are studied by ESR spectroscopy.  -  The 13C coupling constants allow the conclusion that in thio- and selenoketyls the spin density is mainly located at the central carbon atom.  -  The observed temperature dependence of the coupling constants is in agreement with a planar geometry of the thioketyl molecule.
    Notes: Die Darstellung aliphatischer und aromatischer Thio- und Selenoketone sowie einiger ihrer D-, 13C- und 77Se-angereicherten Derivate wird beschrieben.  -  Bei der elektrochemischen Einelektronen-Reduktion liefern die meisten Vertreter persistente Radikalanionen, die ESR-spektroskopisch untersucht werden. Die gemessenen isotropen 13C-Kopplungskonstanten erlauben den Schluß, daß in der Thio- bzw. Selenoketyl-Gruppe die Spinpopulation am zentralen C-Atom am größten ist.  -  Die beobachtete Temperaturabhängigkeit der Kopplungskonstanten ist mit einer planaren Geometrie des Thioketyl-Moleküls in Einklang.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 2221-2228 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thioketyls, 8. Radical Anions of α-Thioxoketones (“Monothiosemidiones”)Radical anions (“monothiosemidiones”) 5 are obtained by in-situ electroreduction of α-thioxoketones. Conclusions about the spin density distribution are drawn from their ESR spectra. The unpaired electron is mainly located in the central CO—CS group. - Only 5a-g exhibit proton hfs splittings, and that for the protons of the thiobenzoyl but not of the benzoyl group. 13C-satellites of the CS- and CH3-carbon atoms are observed in the spectra of 5h-j. From the latter π-spin populations of the thiocarbonyl carbon atom of 0.82 (5h) and 0.54 (5j), respectively, are calculated.
    Notes: Durch in-situ-Elektroreduktion werden α-Thioxoketone in die Radikalanionen („Monothiosemidione“) 5 übergeführt. Aus deren ESR-Spektren lassen sich Rückschlüsse über die Aufenthaltswahrscheinlichkeit des ungepaarten Elektrons ziehen. Die zentrale CO—CS-Gruppe enthält den überwiegenden Teil der Spindichte. - Nur bei 5a-g treten meßbare Protonen-HFS-Aufspaltungen auf, und zwar für die Protonen der Thiobenzoyl- nicht aber der Benzoylgruppen. Bei 5h-j beobachtet man 13C-Satelliten der CS- und CH3-Kohlenstoffatome. Aus letzteren erhält man π-Spinpopulationen am Thiocarbonyl-C-Atom von 0.82 (5h) bzw. 0.54 (5j).
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 575-581 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Coupling constants of the 13C and 33S nuclei are determined from the ESR spectra of specifically labelled di-tert-butyl-monothiosemidione (1-·) and -dithiosemidione (2-·) radical anions, the latter being formed on one-electron reduction of 3,4-di-tert-butyl-1,2-dithiete. Spin densities are calculated from these coupling constants and, especially, from the anisotropic values. - Using the semi-empirical MNDO/Cl and MINDO3/Cl methods including configurational interaction (Cl) the geometries and theoretical spin densities are determined and discussed in terms of the experimental values.
    Notes: Aus den ESR-Spektren spezifisch mit 13C und 33S markierter Derivate werden die Kopplungskonstanten dieser Kerne im Di-tert-butyl-monothiosemidion- (1-·) und -dithiosemidion-Radikalanion (2-·) bestimmt. Letzteres entsteht bei der Einelektronen-Reduktion von 3,4-Di-tert-butyl-1,2-dithiet. Aus den Kopplungs-konstanten - insbesondere den anisotropen Werten - werden die Spindichten erhalten. - Mit Hilfe des semi-empirischen MNDO/Cl- und MINDO 3/Cl-Verfahrens unter Einbeziehung der Konfigurationswechselwirkung (Cl) werden die Geometrien der betrachteten Moleküle sowie theoretische Spindichten ermittelt und den experimentellen Daten gegenübergestellt.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 2065-2068 
    ISSN: 0009-2940
    Keywords: Benzo[c]thiophenes ; Oxidation ; Quinones ; Sulfines ; Diels-Alder reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Unexpected Diels-Alder and Oxidation Reactions of Benzo[c]thiophenesThe oxidation of thiophenes by peracids to form thiophene S-oxides could not be carried out with benzo[c]thiophenes. With the sterically hindered compound 1a the quinones 2 and 3 were produced whereas the anisyl-substituted derivative 1b formed the sulfine 5. Significantly different behaviour of 1a and 1b was also observed for the Diels-Alder reaction with N-phenylmaleimide. The unexpected and unusual adduct 6 was the only product formed from 1a, with low yield though, whereas the normal Diels-Alder adduct was obtained from 1b.
    Additional Material: 1 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 2245-2249 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation fo 1,3-Dithiolanes and 1,3-Dithianes on Electroreduction of ω-Chloroalkyl DithiocarboxylatesCyclic thioacetals of type 4 and 5 are formed by intramolecular nucleophilic attack in the cathodic reduction of the ω-chloroalkyl dithiocarboxylates 1 and 2. The yield of 2-tert-butyl-1,3-dithiane (4a) is 52%, whereas elimination of dithiocarboxylate anions occurs to a considerable extent in the other cases.
    Notes: Bei der kathodischen Reduktion der Dithiocarbonsäure-(ω-chloralkyl)ester 1 und 2 entstehen durch intramolekularen Ringschluß cyclische Thioacetale des Typs 4 und 5. Die Ausbeute erreicht bei 2-tert-Butyl-1,3-dithian (4a) 52%; in den anderen Fällen tritt in erheblichem Maße Eliminierung von Dithiocarboxylat-Ionen ein.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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