Benzindoles. 18. Some electrophilic substitution reactions involving the hydrogen atoms in 4,5,6,7-dibenzindole

The principal electrophilic substitution reactions involving the hydrogen atom of 4,5,6,7-dibenzindole — the Vilsmeier reaction, the Mannich reaction, diazo coupling, and acylation — were studied, and a qualitative comparison of its reactivities with indole and 4,5- and 6,7-benzindoles was made. It was established that 4,5,6,7-dibenzindole has the most clearly expressed electron-donor properties. The structures of the synthesized compounds were proved by data from the IR, UV, PMR, and mass spectra.See [1] for communication 17.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 366–370, March, 1979.