Ringöffnungsreaktionen von Cyclopropyl‐Radikalen, IV. Darstellung und Thermolyse substituierter 1‐Aziridinpercarbonsäure‐tert‐butylester

Organisch-Chemisches Institut der Universität Münster, D-4400 Münster, Orléansring 23
Berichte der deutschen chemischen Gesellschaft (Impact Factor: 2.94). 05/1975; 108(5):1527 - 1532. DOI: 10.1002/cber.19751080521


cis-2,3-Diphenylaziridinyl-Radikale 6, in Äthylbenzol durch Thermolyse des cis-2,3-Diphenyl-1-aziridinpercarbonsäure-tert-butylesters (1) erzeugt, isomerisieren nach den Ergebnissen der Produktanalyse quantitativ zu 1,3-Diphenyl-2-azaallyl-Radikalen 7. trans-2,3-Dimethylaziridinyl-Radikale, die auf zwei Wegen unabhängig erzeugt wurden, lassen sich bis +40°C ESR-spektroskopisch nachweisen, ohne daß eine Valenzisomerisierung feststellbar ist.
Ring opening of Cyclopropyl Radicals, IV. Synthesis and Thermolysis of substituted tert-Butyl 1-Aziridinepercarboxylates
cis-2,3-Diphenylaziridinylradicals 6 were generated by thermolysis of tert-butyl cis-2,3-diphenyl-1-aziridinepercarboxylate (1) in ethylbenzene at 130°C. By product analysis it was shown that the radicals 6 isomerize under the reaction conditions completely to give 1,3-diphenyl-2-azaallyl radicals 7. trans-2,3-Dimethylaziridinyl radicals were generated by two independent methods. Their e.s.r. spectrum can be observed up to + 40°C without the detection of valence isomerisation.

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