Abstract
A method for the introduction of a 3-indolyl group in compounds with an active methylene group was developed. The corresponding 3-indolyl diketones were obtained by condensation of 1-acetyl-3-indolinone with dimedone, 4-hydroxycoumarin, 1,2-diphenyl-3,5-pyrazolinedione, and barbituric and thiobarbituric acids and subsequent alkaline hydrolysis of the condensation products. The existence of cyclic six-membered 3-indolyl diketones in the enol form and of cyclic five-membered 3-indoly diketones in the keto form was shown by IR and UV spectroscopy. Depending on the conditions, (1-acetyl-3-indolyl)cyanoacetamide, 1,3-bis(1-acetyl-3-indolyl)-1,3,3-tricyano-2-amino-1-propene, and 1-acetyl-3-indolylmalononitrile are obtained in the condensation of 1-acetyl-3-indolinone with malononitrile. 1-Acetyl-3-indolylmalononitrile exists in equilibrium with the keteneimine form and in protic solvents is converted to 3-cyano-8-acetylpyrrolo[2,3-b]indole by intramolecular cyclization.
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V. N. Borisova, E. N. Gordeev, and N. N. Suvorov, Khim. Geterotsikl. Soedin., No. 3, 357 (1977).
C. D. Nenitzescu and D. Raileaunu, Ber., 91, 1141 (1958).
N. N. Suvorov, V. S. Velezheva, and V. V. Vampilova, Khim. Geterotsikl. Soedin., No. 4, 515 (1974).
A. N. Kost, I. P. Sugrobova, and A. P. Yakubov, Zh. Org. Khim., 1, 124 (1965).
O. Ya. Neiland and G. Ya. Vanag, Usp. Khim., 34, 436 (1959).
R. Blaut, J. Am. Chem. Soc., 68, 566 (1946).
M. R. Weir and J. B. Hyne, Can. J. Chem., 41, 2905 (1963).
T. R. Kasturi, V. K. Sharma, A. Srinivasan, and G. Subrahmanyam, Tetrahedron, 29, 4103 (1973).
S. Trofimenko, J. Org. Chem., 28, 217 (1963).
A. Albert and E. Serjeant, Ionization Constants of Acids and Bases, Methuen (1962).
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 360–368, March, 1977.
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Velezheva, V.S., Sevodin, V.P., Erofeev, Y.V. et al. Indole derivatives. Chem Heterocycl Compd 13, 290–297 (1977). https://doi.org/10.1007/BF00470313
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DOI: https://doi.org/10.1007/BF00470313