Halochromism of thiophene-containing analogs of chalcones and their derivatives

The formation of hydroxy-, acyloxy-, chloro-, and tetrachlorophosphoroxycarbonium ions was established on the basis of the electronic absorption spectra of thiophene-containing analogs of chalcones and their derivatives in concentrated sulfuric acid, in dilute solutions of sulfuric acid in acetic and trichloroacetic anhydrides, and in acetonitrile benzene, dichloroethane, and nitromethane in the presence of phosphorous pentachloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1361–1364, October, 1971.