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  • 1
    Electronic Resource
    Electronic Resource
    Thioketyle, 9 ESR-Untersuchungen und semi-empirische MO-Rechnungen an aliphatischen Mono- und Dithiosemidion-Radikalanionen (1987)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 575-581 
    Details
    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
    URL: http://dx.doi.org/10.1002/cber.19871200418
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  • 2
    Electronic Resource
    Electronic Resource
    Thioketyle, 8. Radikalanionen von α-Thioxoketonen („Monothiosemidione“) (1982)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 2221-2228 
    Details
    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
    URL: http://dx.doi.org/10.1002/cber.19821150618
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  • 3
    Electronic Resource
    Electronic Resource
    The He(Iα) Photoelectron Spectra of Substituted 1,2-Dithietes (1983)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 66 (1983), S. 801-808 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The He(Iα) photoelectron (PE.) spectra of a series of substituted 1,2-dithietes have been recorded and assigned with respect to the orbital sequence derived from an STO-3G model calculation and by correlation with the PE. spectra of related compounds. The results provide additional support for the presence of a closed, four-membered ring moiety in all the 1,2-dithietes investigated. In all cases the two highest occupied molecular orbitals are b2(π)= HOMO, a2(π), with exception of 3,4-bis(trifluoromethyl)-1,2-dithiete where the sequence b2(π), a2(π) or a2(π), b2(π) is uncertain.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19830660312
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  • 4
    Electronic Resource
    Electronic Resource
    Darstellung von Diaryl- und Aryl-tert-butyl-α-thioxoketonen (1981)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1981 (1981), S. 10-19 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of Diaryl and Aryl tert-Butyl α-ThioxoketonesThe preparation of the α-haloketones 6, 13-16, 19, and 20 is reported. 13 or its precursor, the acyloin 9, respectively, is conveniently obtained by a Seebach synthesis.  -  Reaction of the haloketones with tetraethylammonium thiosulfate (21) yields the Bunte salts 22-27 which form the thioketones 28-33 on cleavage with aqueous alkali. 29 is stable as a crystalline, blue monomer in contrast with other aromatic α-thioxoketones. This ist also true for the aromatic-aliphatic derivatives 30 and 31 as well as their isomers 32 and 33 which do not dimerize.
    Notes: Die Darstellung der α-Halogenketone 6, 13-16, 19 und 20 wird beschrieben. 13, bzw. seine Vorstufe 9, ist am besten durch eine Seebach-Synthese zugänglich.  -  Durch Umsetzung mit Tetraethylammonium-thiosulfat (21) erhält man aus den Halogenketonen die Bunte-Salze 22-27, die nach Spaltung mit Alkali die Thioketone 28-33 liefern. 29 ist im Gegensatz zu anderen aromatischen α-Thioxoketonen als kristallisiertes blaues Monomeres beständig. Auch die aromatisch-aliphatischen Vertreter 30 und 31 sowie ihre Isomeren 32 und 33 dimerisieren nicht.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198119810104
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