Electronic effects in dianion radicals of nitro derivatives of 2-phenylbenzimidazole
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The EPR spectra of the dianion radicals of 5(6)-nitro-2-(4-aminophenyl)benzimidazole (I), 5(6)-nitro-2-phenylbenzimidazole (II), 5(6)-nitro-2-(4-nitrophenyl)benzimidazole (III), 5(6)-nitro-2-(3-nitrophenyl)benzimidazole (IV), and 2-(4-nitrophenyl) benzimidazole (V), obtained by electrochemical reduction in dimethylformamide (DMF) in a Bu4NClO4 -base electrolyte in the presence of Bu4NOH (VI), were studied. Under the influence of VI, these compounds split out a proton from the imidazole ring and give anions I–V, which are capable of adding an electron reversibly. It was shown that the unpaired electron in I and II is localized in the benzimidazole system and that the splitting of the nitrogen atom of the nitro group does not depend significantly on the substituent in the phenyl ring. The introduction of a nitro group in the phenyl ring (III–V) leads to localization of the unpaired electron on it. The nature of the substituent in the benzimidazole system has a significant effect on the splitting constant for the nitrogen atom of the nitro group.
KeywordsImidazole Nitrogen Atom Benzimidazole Phenyl Ring Dimethylformamide
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- 1.P. G. Haines and E. C. Wagner, J. Am. Chem. Soc., 71, 2793 (1949).Google Scholar
- 2.I. M. Sosonkin, G. N. Strogov, G. E. Troshin, V. K. Shchel'tsyn, and N. V. Fedyainov, Summaries of Papers Presented at the Third All-Union Conference on Charge-Transfer Complexes and Ion-Radical Salts [in Russian], Zinatne, Riga (1976), p. 112.Google Scholar
- 3.R. D. Allendoerfer and P. H. Rieger, J. Chem. Phys., 46, 3266 (1967).Google Scholar
- 4.T. Fujinaga, Y. Deguchi, and K. Umemoto, Bull. Chem. Soc. Jpn., 37, 822 (1964).Google Scholar
- 5.I. M. Sosonkin, A. N. Domarev, É. G. Kaminskaya, A. I. Tolstikov, F. F. Lakomov, and A. Ya. Kaminskii, Zh. Prikl. Khim., 44, 950 (1971).Google Scholar
- 6.I. M. Sosonkin, A. Ya. Kaminskii, S. S. Gitis, and É. G. Kaminskaya, Dokl. Akad. Nauk SSSR, 197, 635 (1971).Google Scholar
- 7.S. N. Dobryakov, Zh. Struk. Khim., 6, 39 (1965).Google Scholar
- 8.A. Bartl, Z. Naturforsch., 23a, 1975 (1968).Google Scholar