Synthesis of o-Quinones of 3H-Benzindole

Article abstract of DOI:10.1007/BF00505760

4,5-Dioxo-4,5-dihydro-3H-benzindole derivatives were synthesized from 3-nitro-o-naphthoquinones with keto enol residues in the 4 position.One of these products was methylated at the nitrogen atom of the pyrrole ring.The N-methyl derivative was used for the synthesis of a phenazine.