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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 107-124 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloheptadecaoctaenes and [17]Annulenyl AnionsThe dimer 1 of cyclooctatetraene reacts with “methylene” and ethoxycarbonylcarbene to yield different monoadducts 2 and 7-10. From the esters 7-10 the acids 11-13 are available. All endocyclic σ-bonds of the tetracyclic compounds 2,8,11-13 are cleaved by UV light with formation of the cycloheptadecaoctaenes 15-17.17 decarboxylates in acetone cleanly to give crystalline cycloheptadecaoctaene (18). In the presence of bases, the carbon acids 15 and 18 are converted into the [17] annulenyl anion (19). An analogous behaviour is shown by 20 and 22 which yield the same mixture of methyl[17]annulenyl anions (21). Some properties of the seventeen-membered higher vinylogues of cyclopentadiene and cyclopentadienyl anion are investigated.
    Notes: Dimeres Cyclooctatetraen 1 reagiert mit „Methylen“ und Ethoxycarbonylcarben zu verschiedenen Monoaddukten 2 und 7-10. Aus den Estern 7-10 sind die Säuren 11-13 zugänglich. In den Tetracyclen 2, 8, 11-13 brechen unter der Einwirkung von UV-Licht alle endocyclischen σ-Bindungen auf. Es entstehen die Cycloheptadecaoctaene 15-17. 17 decarboxyliert in Aceton glatt zum kristallinen Cycloheptadecaoctaen (18). Die Kohlenstoffsäuren 15 und 18 bilden in Gegenwart von Basen das [17]Annulenyl-Anion (19). Analoges Verhalten zeigen 20 und 22. Man erhält das gleiche Gemisch von Methyl[17]annulenyl-Anionen (21). Einige Eigenschaften der siebzehn-gliedrigen höheren Vinylogen des Cyclopentadiens und Cyclopentadienyl-Anions werden untersucht.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses and Some Properties of Mono- and Disubstituted Bicyclo[4.2.2]decatetraenesWe report the syntheses of the mono- and disubstituted bicyclo[4.2.2]decatetraenes 12 ⇌ 13, 14 ⇌ 15, 16, 17 ⇌ 18, 24 and 19, 20, respectively. The Diels-Alder/retro-Diels-Alder reaction possible in these molecules gives rise to a detectable equilibrium mixture between two valence isomers in the case of 12 ⇌ 13, 14 ⇌ 15 and 17 ⇌ 18. The half-lives of the molecules 13, 18, and 24 at 35°C are of the order of 13 to 24 minutes.  -  We also describe some experiments designed to detect a didehydrobicyclo[4.2.2]decatetraene 37 or 38.
    Notes: Wir berichten über die Darstellungen der mono- und disubstituierten Bicyclo[4.2.2]decatetraene 12 ⇌ 13, 14 ⇌ 15, 16, 17 ⇌ 18, 24 bzw. 19, 20. Die in diesen Molekülen mögliche Diels-Alder/Retro-Diels-Alder-Reaktion führt bei 12 ⇌ 13, 14 ⇌ 15, 17 ⇌ 18 zu einem nachweisbaren Gleichgewichtsgemisch zwischen zwei Valenzisomeren. Die Halbwertszeiten der Verbindungen 13, 18 und 24 liegen bei 35°C zwischen ca. 13 bis 24 Minuten.  -  Wir informieren ferner über einige Versuche zum Nachweis eines Didehydrobicyclo[4.2.2]decatetraens 37 oder 38.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1979 (1979), S. 533-546 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of Substituted Bicyclo[4.3.1]decatrienyl CationsThe rearrangement of bicyclo[4.2.2]decatetraenes to bicyclo[4.3.1]decatrienes on addition of electrophiles opens a route to methano-bridged dihomotropylium ions. We report here on some substituted cations, namely 2-methyl- (16), 2-chloro- (22), 2-bromo- (26), 2,5-dimethyl- (29), 1-methyl- (37), 1-chloro- (38), 1-bromo- (39), 7-phenyl- (42) and the 7-(2-methoxyphenyl)bicyclo]4.3.1]decatrienylcation (44). Cyclic π-electron delocalization in the bicyclo[4.3.1]-decatrienyl cation (1) is more or less disturbed but never suppressed by the substituents mentioned.-3-Methylbicyclo[4.2.2]decatetraene (30) behaves atypically on addition of HBr. 10-exo-Methoxy-4-methyltricyclo[4.3.1.02,9]deca-3,7-diene (33) is isolated after solvolysis with methanol. A mechanistic interpretation is given.
    Notes: Bicyclo[4.2.2]decatetraene lagern sich im Regelfall bei der elektrophilen Addition in Bicyclo[4.3.1]decatriene um. Das erschließt einen Zugang zu methanoüberbrückten Dihomotropyliumionen. In dieser Arbeit berichten wir über einige substituierte Kationen. Es sind dies das 2-Methyl- (16), 2-Chlor- (22), 2-Brom- (26), 2,5-Dimethyl- (29), 1-Methyl- (37), 1-Chlor- (38), 1-Brom- (39), 7-Phenyl- (42) und 7-(2-Methoxyphenyl)bicyclo[4.3.1]decatrienylkation (44). Die cyclische π-Elektronendelokalisation im Bicyclo[4.3.1]decatrienylkation (1) wird durch die genannten Substituenten mehr oder weniger gestört aber nicht unterbunden.-3-Methyl-bicyclo[4.2.2]decatetraen (30) zeigt bei der HBr-Addition atypisches Verhalten. Nach der Methanolyse liegt 10-exo-Methoxy-4-methyltricyclo[4.3.1.02,9]deca-3,7-dien (33) vor. Eine mechanistische Deutung wird angegeben.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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