Abstract
Electrochemical reduction in dimethylformamide of unsymmetrical 1-Cl-4-X-phthalazines and symmetrical 1,4-X2-phthalazines (X = Cl, PhO, MeO, EtO, i-PrO) was studied by voltammetry and electrolysis-ESR. The electron trasfer on 1,4-dichlorophthalazine and unsymmetrical 1-Cl-4-X-phthalazines induces anionoid elimination of Cl and X, pyridazine ring cleavage, and phthalonitrile formation. In this previously unknown process the transfer of two electrons induces cleavage of three σ bonds and formation of two new π bonds. The reduction of 1,4-dialkoxy(diaryloxy)phthalazines involves formation of stable radical anions which undergo no heteroring cleavage. Possible mechanisms of the processes studied were discussed. It was assumed that the same mechanism with pyridazine ring cleavage may be realized with other phthalazine derivatives and heteroannelated pyridazines containing readily leaving nucleofuge groups α to nitrogens.
Similar content being viewed by others
REFERENCES
Plump, R.E. and Hammet, L.P., Trans. Electrochem. Soc., 1938, vol. 73, Chem. Abstr., 1938, vol. 32, no. 7, no. 24 368.
Butin, K.P., Usp. Khim., 1971, vol. 40, no. 6, p. 1058.
Berdnikov, E.A., Fedorov, S.B., and Kargin, Yu.M., Zh. Obshch. Khim., 1978, vol. 48, no. 4, p. 875.
Chechina, O.N. and Tomilov, A.P., Elektrokhimiya, 1999, vol. 35, no. 2, p. 149.
Taran, L.A., Buzykin, B.I., Mironova, O.Yu., Gazetdinova, N.G., and Kitaev, Yu.P., Izv. Akad. Nauk SSSR, Ser. Khim., 1983, no. 1, p. 166.
Sosonkin, I.M., Strogov, G.N., Novikov, V.N., and Ponomareva, T.K., Khim. Geterotsikl. Soedin., 1977, no. 1, p. 23.
Sosonkin, I.M., Strogov, G.N., Ponomareva, T.K., Domaraev, A.N., Glushkova, A.A., and Freidlin, G.N., Khim. Geterotsikl. Soedin., 1981, no. 2, p. 195.
Alwair, K. and Grimshaw, J., J. Chem. Soc., Perkin Trans. 2, 1973, no. 13, p. 1811.
Fuchs, P., Hess, U., Holst, H.H., and Lund, H., Acta Chem. Scand., 1981, no. 3, p. 185.
Sosonkin, I.M. and Strogov, G.N., Khim. Geterotsikl. Soedin., 1982, no. 8, p. 1126.
Shimanskaya, N.P., Kotok, L.A., and Alekhina, T.F., Zh. Obshch. Khim., 1976, vol. 46, no. 10, p. 2346.
Khmel'nitskaya, E.Yu., Zh. Obshch. Khim., 1977, vol. 47, no. 5, p. 1158.
Supin, G.S., Fainshraiber, M.Ya., Mel'nikova, I.A., Mel'nikov, I.A., and Motorova, T.N., Zh. Obshch. Khim., 1977, vol. 47, no. 10, p. 2338.
Ivanova, V.Kh., Buzykin, B.I., and Bystrykh, N.N., Khim. Geterotsikl. Soedin., 1979, no. 4, p. 541.
Buzykin, B.I., Yanilkin, V.V., Morozov, V.I., Maksimyuk, N.I., and Eliseenkova, R.M., Abstracts of Papers, Mezhdunarodnaya Nauchnaya Konferentsiya “Organicheskii sintez i kombinatornaya khimiya” (Int. Sci. Conf. “Organic Synthesis and Combinatorial Chemistry”), Moscow, 1999, P-27.
Buzykin, B.I., Yanilkin, V.V., Morozov, V.I., Maksimyuk, N.I., Eliseenkova, R.M., and Nastapova, N.V., Mendeleev. Commun., 2000, no. 1, p. 34.
Buzykin, B.I., Yanilkin, V.V., Morozov, V.I., Eliseenkova, R.M., and Maksimyuk, N.I., Izv. Ross. Akad. Nauk, Ser. Khim., 2000, no. 1, p. 181.
Stone, E.W. and Maki, A.H., J. Chem. Phys., 1963, vol. 39, no. 7, p. 1635.
Wiberg, K. and Lewis, Th.P., J. Am. Chem. Soc., 1970, vol. 92, no. 24, p. 7154.
Lund, H. and Jensen, E.Th., Acta Chem. Scand., 1970, vol. 24, no. 6, p. 1867.
Rieger, P.H., Bernal, J., Reinmuth, W.H., and Fraenkel, G.K., J. Am. Chem. Soc., 1963, vol. 85, no. 6, p. 683.
Mann, C.K. and Barnes, K.K., Electrochemical Reactions in Nonaqueous Media, New York: Dekker, 1970. Translated under the title Elektrokhimicheskie reaktsii v nevodnykh sistemakh, Moscow: Khimiya, 1974, p. 194.
Mairanovskii, V.G., Elektrosintez monomerov (Electrosynthesis of Monomers), Moscow: Nauka, 1980, p. 244.
Buzykin, B.I., Bystrykh, N.N., Stolyarov, A.P., Flegontov, S.A., Zverev, V.V., and Kitaev, Yu.P., Khim. Geterotsikl. Soedin., 1976, no. 3, p. 402.
Cook, J.C.S., Katrizkiy, A.R., Page, A.D., and Ramaian, M., J. Chem. Soc., Perkin Trans. 2, 1973, no. 9, p. 1184.
Mairanovskii, V.G., Dokl. Akad. Nauk SSSR, 1985, vol. 284, no. 2, p. 386.
Yanilkin, V.V., Doctoral (Chim.) Dissertation, Kazan, 1998.
Yanilkin, V.V., Berdnikov, E.A., and Buzykin, B.I., Elektrokhimiya, 2000, vol. 36, no. 2, p. 146.
Druey, J. and Ringer, B.H., Helv. Chim. Acta, 1951, vol. 34, no. 21, p. 195.
Rowe, F.M. and Peters, A.T., J. Chem. Soc., 1933, p. 1331.
Elvidge, J.A. and Redman, A.P., J. Chem. Soc., 1960, no. 4, p. 1710.
Braun, A. and Tcherniac, J., Ber., 1907, no. 40, part 2, p. 2709.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Yanilkin, V.V., Buzykin, B.I., Morozov, V.I. et al. Electrochemical Reduction of 1,4-Disubstituted Phthalazines. Russian Journal of General Chemistry 71, 1636–1646 (2001). https://doi.org/10.1023/A:1013979709884
Issue Date:
DOI: https://doi.org/10.1023/A:1013979709884