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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 339-349 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Mode of Reaction of Methylene Cyclopropenes with Diazo AlkanesThe reactions of diazomethane, diazoethane and 1-diazopropane with methylene cyclopropenes 8 and 15 are investigated. 8 yields pyridazine derivatives; with diazoethane the cyclic azo compound 12 is obtained as an intermediate of pyridazine formation. 15 yields pyrazolenine derivatives which are transformed thermally either to pyrazole 20 or to the cyclopropene derivatives 17a and b. The reaction mechanisms are discussed.
    Notes: Die Umsetzungen von Diazomethan, Diazoäthan und 1-Diazo-propan mit den Methylen-cyclopropenen 8 und 15 werden untersucht. 8 ergibt Pyridazin-Derivate, im Falle des Diazoäthans wird als Zwischenstufe die cyclische Azoverbindung 12 gefaßt. 15 liefert Pyrazolenin Derivate, die thermisch zum Pyrazol 20 bzw. Den Cyclopropenen 17 a und b umgewandelt werden. Die Reaktionsmechanismen werden diskutiert.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1980 (1980), S. 409-415 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thermolysis of ortho-Chloro-Substituted 1,2-DiarylethylenediaminesOn heating bis(2,6-dichlorophenyl)ethylenediamines 1a - d give indoles and  -  in the case of the racemates 1b and d  -  tetrahydroindoloindoles. The d,1-form of the corresponding 2,4-dichloro compound 1f leads to a 2,4,5-triarylimidazolidine, the meso-form 1e to an aziridine, whose formation via a 2,cis-4,5-triarylimidazolidine appears likely from mechanistic considerations.
    Notes: Die Bis(2,6-dichlorphenyl)ethylendiamine 1a - d reagieren bei der Thermolyse zu Indolen und im Falle der Racemate 1b und d auch zu Tetrahydroindoloindolen. Die d,1-Form der entsprechenden 2,4-Dichlorverbindung 1f führt zu einem 2,4,5-Triarylimidazolidin, die meso-Form 1e zu einem Aziridin, dessen Bildung über ein 2,cis-4,5-Triarylimidazolidin durch mechanistische Betrachtungen wahrscheinlich gemacht werden konnte.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 746 (1971), S. 120-133 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Triafulvenes with N-, S- and P-ylides, II1). Allylpyridinium Betaines and TriafulvenesThe allylbetaine 5a reacts with diphenylcyclopropenone (1a) in aprotic solvents forming 2,3,6-triphenylphenol (10). In protic solvents 1a and 5a-c give the esters 12 of Δ3.5-hexadienoic acid. 1,2-Diphenyl-3-diacetylmethylenecyclopropene (1b) yields with 5a and 5c the fulvenes 20a and 20c, respectively, in addition with 5a 2,3,6-triphenyl-1-diacetylmethylbenzene (19) and the acetylene 23. The structure of the products is proved by spectral data, chemical degradation and independent synthesis. From their formation a ketene-allene mechanism (pages 123, 127) seems to be very likely.
    Notes: Das Allylbetain 5a reagiert mit Diphenylcyclopropenon (1a) in aprotischem Solvens zu 2.3.6-Triphenyl-phenol (10). In protischem Solvens entstehen dagegen mit 5a-c Δ3.5-Hexadiensäureester 12. - 1.2-Diphenyl-3-diacetylmethylen-cyclopropen (1b) ergibt mit 5a und 5c die Fulven-Derivate 20a bzw. 20c, mit 5a zusätzlich 2.3.6-Triphenyl-1-diacetylmethyl-benzol (19) und das Acetylen 23. Die Konstitution der erhaltenen Produkte wird durch ihre Spektren, Abbaureaktionen und unabhängige Synthese bewiesen. Ihre Bildung macht einen Keten-Allen-Mechanismus (S. 123, 127) sehr wahrscheinlich.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 746 (1971), S. 102-119 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Triafulvenes with N-, S- and P-Ylides, I. Enol Betaines and TriafulvenesPyridinium-, diethylsulfonium- and triphenylphosphonium-enolbetaines (3, 16 and 17, respectively) react with cyclopropenones forming pyrones-(2) 5 (table 1). 3-Diacylmethylene-cyclopropenes yield 2-diacylmethylene-pyranes 14 with 3 and 16, while with 17 derivatives 21 of methylenecyclobutene. The structure of the different products is elucidated by means of spectral data, chemical reactions and independent syntheses. The mechanism of their formation is discussed.
    Notes: Pyridinium-, Diäthylsulfonium- und Triphenyl-phosphonium-enolbetaine (3 bzw. 16 bzw. 17) reagieren mit Cyclopropenonen zu Pyronen-(2) 5 (Tab. 1). 3-Diacylmethylen-cyclopropene ergeben mit 3 und 16 2-Diacylmethylen-pyrane 14, mit 17 jedoch Derivate 21 des Methylencyclobutens. Die Struktur der erhaltenen Produkte wird durch Spektren, chemische Reaktionen und unabhängige Synthesen gesichert; ihr Bildungsmechanismus wird diskutiert.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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