Indolizines. Part V. The synthesis of 3-amino- and 3-acetamido-indolizines and their precursors, the 3-azo-, -nitroso-, -nitro-, and -acetyl-indolizines

Abstract

The most convenient method for the preparation of 3-aminoindolizines has been shown to be the rapid reduction of 3-nitrosoindolizines by means of hydrazine hydrate in the presence of palladium–charcoal. The amines have also been prepared by similar reduction of 3-nitro- and 3-azoindolizines, and, as their acetyl derivatives, by the Schmidt reaction from 3-acetylindolizines. Indolizine and 2-methylindolizine have, for the first time, been nitrated in the 3-position by the use of acetic anhydride and nitric acid; the implications of this reaction are discussed.