Summary
The oxidation of 2,2-Diacyl-1-arylhydrazines1a–l with the system Pb(OAc)4-CF3COOH-CH2Cl2 led to the formation of two types of radical products. Phenazinium cation radicals5a–h were formed from 2,2-diacyl-1-arylhydrazines1a–h, while hydrazyl radicals2i–l were observed to be the only radical products of the oxidation of1i–l. The generated radicals are characterized by their EPR parameters.
Zusammenfassung
Die Oxidation der 2,2-Diacyl-1-arylhydrazine1a–l mit dem System Pb(OAc)4-CF3COOH-CH2Cl2 führte zu zwei unterschiedlichen Typen von Radikalen. Aus den 2,2-Diacyl-1-arylhydrazinen1a–h werden die Phenaziniumkationenradikale5a–h gebildet, während nach Oxidation von1i–l die entsprechenden Hydrazyle2i–l als einzige Radikalprodukte nachweisbar waren. Die erzeugten Radikale wurden durch ihre EPR-Parameter charakterisiert.
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References
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The hydrazoxyl radical41(g=2.0057) can be prepared by the oxidation of1l with t-BuO ·2 radicals generated by the decomposition of t-BuOOH with PbO2. EPR parameters in mT (a NON =1.302, aN=0.194, a 0H =0.160, a mH =0.095 (1H), a mH =0.058 (1H)) document ortho effect of the tert-butyl group also in this case, especially when compared with EPR data of other hydrazoxyls4 [2].
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Omelka, L., Kluge, R. & Schulz, M. Radical products of the oxidation of 2,2-diacyl-1-arylhydrazines with the system Pb(OAc)4-CF3COOH-CH2Cl2 . Monatsh Chem 126, 155–161 (1995). https://doi.org/10.1007/BF00812244
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DOI: https://doi.org/10.1007/BF00812244