Synthesis of polynuclear heterocycles. Part III. Imidazo[4,5-f]benzofuroxans and -furazans

Abstract

Several examples of the hitherto unreported imidazo[4,5-f]benzofuroxan ring system have been prepared by both thermal (135°) and photolytic decomposition of the appropriate azidonitrobenzimidazoles. Pyrolysis of the nitroazides at higher temperature (180–190°) gave the corresponding imidazo[4,5-f]furanzans. The ¹H n.m.r. and u.v. spectra are recorded.

Some new 6-amino-5-nitro- and 5-amino-6-nitro-benzimidazoles are reported.