Asymmetric and symmetric annellation effects—III Benzocoronenes

1:2–5:6-Dibenzocoronene (IV) was obtained from 1:2–4:5–8:9-tribenzopyrene (II) via the dianhydride (III). 1:2–4:5-Dibenzopyrene (V) condensed twice with maleic anhydride. The resulting dianhydride (VI) gave 1:2-benzocoronene (VII) on decarboxylation. 1:12-o-Phenyleneperylene (X) was obtained by a zinc dust melt from the quinone (VIII). The annellation effects passing from triphenylene and perylene to the benzocoronenes indicate the presence of a triphenylene complex within the electronic fine structure of coronene.