Russian Journal of Organic Chemistry

, Volume 48, Issue 3, pp 434–438 | Cite as

Prototropic isomerization of dihydropyridazinecarboxylic and dihydropyridazinedicarboxylic acid esters

Article

Abstract

3,5-Disubstituted 1,4-dihydropyridazine-4-carboxylic and 4,6-disubstituted 2,5-dihydropyridazine-3,5-dicarboxylic acid esters undergo isomerization into 2,5-dihydropyridazine-4-carboxylate and 1,4-dihydropyridazine-3,5-dicarboxylate derivatives, respectively, by the action of a catalytic amount of a mineral acid or strong base at 20°C. The transformation may be regarded as prototropic rearrangement, and it includes two consecutive 1,2-hydride shifts. The direction of the isomerization is determined by higher thermodynamic stability of the isomer containing a β-aminoacrylate fragment.

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References

  1. 1.
    Razin, V.V., Yakovlev, M.E., Shataev, K.V., and Selivanov, S.I., Russ. J. Org. Chem., 2004, vol. 40, p. 1027.CrossRefGoogle Scholar
  2. 2.
    Yakovlev, M.E. and Razin, V.V., Russ. J. Org. Chem., 2004, vol. 40, p. 1033.CrossRefGoogle Scholar
  3. 3.
    Schmidt, M.W., Baldridge, K.K., Boatz, J.A., Elbert, S.T., Gordon, M.S., Jensen, J.J., Koseki, S., Matsunaga, N., Nguyen, K.A., Su, S., Windus, T.L., Dupuis, M., and Montgomery, J.A., J. Comput. Chem., 1993, vol. 14, p. 1347; Nemukhin, A.V., Grigorenko, B.L., and Granovskii, A.A., Vestn. Mosk. Univ., Khim., 2004, vol. 45, p. 75.CrossRefGoogle Scholar
  4. 4.
    MarvinBeans 5.3.7; http://www.chemaxon.com.
  5. 5.
    Rocha, G.B., Freire, R.O., Simas, A.M., and Stewart, J.J.P., J. Comput. Chem., 2006, vol. 27, p. 1101.CrossRefGoogle Scholar
  6. 6.
    Vasin, V.A. and Razin, V.V., Synlett, 2001, p. 658.Google Scholar
  7. 7.
    Breslow, R. and Battiste, M., Chem. Ind., 1958, p. 1143.Google Scholar

Copyright information

© Pleiades Publishing, Ltd. 2012

Authors and Affiliations

  1. 1.St. Petersburg State UniversitySt. PetersburgRussia
  2. 2.Ogarev Mordovian State UniversitySaranskRussia

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