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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 67 (1995), S. 1472-1476 
    ISSN: 0009-286X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The kinetics of the autoxidation of 2,3-dimethylbutadiene (1,3) yielding polymeric peroxides have been investigated and compared with the spontaneous autoxidation of the Me-ester of 10,12-octadecadienoic acid. Both reactions are shown to be of autocatalytical character: the rate of autoxidation is proportional to the square root of mole O2/mole diene. The peroxides split into radicals starting autoxidation chains in a monomolecular manner. The energies activation have been determined.The influences of azoisobutyronitrile, ascaridole, di-tert. -butylperoxide and copper salt of α-ethylcaproic acid on the autoxidation of the Me-ester of 10,12-octadecadienoic acid have been investigated. The result of all is that polymeric peroxides are formed.
    Notes: Die spontane Autoxydation des Dimethylbutadiens, die zu polymeren Peroxyden führt, wird kinetische verfolgt und mit der Autoxydation des konjugierten 10, 12-Octadecadiensäuremethylesters verglichen. Beide Reaktionen verlaufen autokatalytisch. Die Reaktionsgeschwindigkeit ist zu Beginn der Wurzel aus dem Autoxydationsgrad (Mol O2/Mol Substrat) proportional. Die gebildeten Peroxyde zerfallen monomolekular in kettenstartende Radikale. Die Brutto-aktivierungsenergieen werden angegeben.Die Einwirkung von Azodiisobuttersäurenitril, Ascaridol, Di-tert.-Butylperoxyd und Cu++ -oktoat auf die Autoxydation des 10,12-Octadecadiensäuremethylesters wird untersucht. Es ergibt sich, daß auch die Autoxydation des konjugiert-ungesättigten Fettsäure-esters zu polymeren Peroxyden führt.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The polymeric peroxides of dimethylbutadiene, isoprene and cyclopentadiene are thermally decomposed and the fragments analyzed. The content of 1,2-structure of the polymeric peroxide of dimethyl-butadiene is about 40-50%, of the polymeric peroxides of isoprene nearly 25%. The polymeric peroxide of cyclopentadiene has only 1,4-structure.The reaction of the polymeric peroxides with perbenzoic acid had been investigated. The presence of peroxy groups in α-position to an ethylenic bond changes their reactivity with perbenzoic acid, decreasing the reactivity of internal double bonds.
    Notes: Die polymeren Peroxyde von Dimethylbutadien, Isopren und Cyclopentadien werden thermisch zersetzt und die erhaltenen Bruchstücke untersucht. Quantitative Bestimmungen von Formaldehyde ergeben, daß das polymere Dimethylbutadienperoxyd zu 40 bis 50%, das polymere Isopreperoxyd zu etwa 25% aus 1,2-Copolymerisaten der Diene mit molekularem Sauerstoff bestehen. Das polymere Cyclopentadienperoxyd entsteht dagegen anscheinend nur durch 1,4-Addition, da der Nachweis des für ein 1,2-Copolymerisat als Zersetzungsprodukt zu erwartenden Glutaconsäuredialdehyds nicht gelang.Es wird außerdem versucht, mit Perbenzoesäure die bei 1,4-Autoxydation zu erwar-tenden kettenständigen Doppelbindungen neben den bei 1,2-Autoxydation zu erwarten-den Vinylseitenketten zu bestimmen. Die Anwesenheit einer peroxydischen Gruppe in α-Stellung zu einer Doppelbindung ändert deren Reaktionsfähigkeit mit der Persäure; sie ist bei kettenständigen Doppelbindungen vermindert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 18 (1956), S. 406-413 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The Me-ester of 9,11-octadecadienoic acid reacts in 1.2 and 1.4-position with moleculare oxygen to give relatively low molecular oxygen-copolymers. These polymeric peroxides produce autocatalyzing effects in the authoxidation reaction. They are rather resistent and can be stored without showing formation of aldehydes. The reaction of perbenzoic acid with external and internal double bounde standing in α-position to peroxy groups was studied at the examples of allyl-tert.-butyl peroxide and cyclohexenylmethyl peroxide.
    Notes: 9,11-Octadecadiensäuremethylester reagiert mit molekularem Sauerstoff in 1,2- und 1,4-Stellung unter Bildung von relative niedermolekularen Sauerstoff-Copolymerisation. Diese polymeren Peroxyde sind bei der Authoxydation autokatalytisch wirksam. Sie sind recht beständig; die buldung von Aldehyden wurde dei der Aufbewahrung nicht beobachtet. Die Reaktion von end- und von kettenständigen Doppelbindungen, die in Nachbarschaft zu Peroxygruppen stechen, mit Perbenzoesäure wird am Beispiel des Allyl-tert.-Butyl- und des Cyclohexenylmethylperoxyds untersucht.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 223-229 
    ISSN: 0009-2940
    Keywords: Porphyrin-quinone cyclophanes ; Photoinduced electron transfer ; Absorption and emission spectra of porphyrin-quinone cyclophanes ; Photosynthesis models ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Syntheses and spectroscopic properties of the porphyrin-quinone cyclophanes 1, 2 and 3 of which structural and/or conformational studies have recently reported[1] are described. Physical properties related to photoinduced electron-transfer reactions like redox potentials, absorption and emission spectra were determined for these compounds.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0009-2940
    Keywords: Photosynthesis models ; Photoinduced electron transfer ; Porphyrin-quinone cyclophanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: To study the structure dependence of photoinduced electron transfer between porphyrins and quinones the concept of a new family of porphyrin-quinone cyclophanes with vertical arrangements of porphyrin and quinone units is presented. The syntheses of the quinone-porphyrin-quinone cyclophane 1, the prototype of this series, and of the quinone-porphyrindonor cyclophanes 12 and 14 are described. Spectroscopic data are discussed with regard to the structures involved and in relation to electron-transfer reactions occurring in these systems.
    Type of Medium: Electronic Resource
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