Systèmes Aromatiques à 10 Électrons π Dérivés de l'Aza-3a-pentalène: XXVI—Etude de quelques Dérivés Polyazapentaléniques en Résonance du Carbone-13

The ¹³C n.m.r. study of nine azapentalenes was carried out and all the signals were assigned. In one case, very unusual couplings between the carbon atoms and the proton bonded to the pyrrole nitrogen atom were observed. The usefulness of ¹³C n.m.r. spectroscopy for the study of annular tautomerism is demonstrated.