Interaction of acyl derivatives of the Fischer base with meta-substituted phenols. Synthesis of 2H- and 4H-spirochromenes of the indoline series

Acyl derivatives of the Fischer base react in the presence of phosphorus oxychloride with m-diethylaminophenol or resorcinol, forming spiro (indoline-2,2-2H]chromenes) and spiro(indoline-2,4-4H]chromenes). The ratio of the isomers depends on the solvent and the substituent in the phenol. The structure of the compounds obtained was established on the basis of the data of the ¹H and ¹³C NMR spectra.Translated from Khimiya Geterosiklicheskikh Soedinenii, No. 8, pp. 1101–1104, August, 1984.