New pyrylium derivatives in the indole series

Nitrogen-unsubstituted 2,3-dihydroindole and its homologs, as well as 1,2,3,4-tetrahydro-- carbolines, react with 2,6-dimethyl-4-methoxypyrylium perchlorates to give N-pyrylated derivatives of indole, which are converted to the corresponding pyridine bases by the action of ammonium salts and form 1-aminopyridinium derivatives with hydrazine hydrate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1531–1533, November, 1972.