Naphthazarin-Polycyclic Conjugated Hydrocarbons and Iptycenes

The
synthesis of a set of naphthazarin-containing polycyclic conjugated
hydrocarbons is described herein. Sequential Diels–Alder reactions
on a tautomerized naphthazarin core were employed to access the final
conjugated systems. Complete conjugation across the backbone can be
achieved through complexation with BF2, as observed by 1H NMR analysis and UV/vis spectroscopy. Precise synthetic
control over the degree of oxidation of naphthazarin quinone Diels–Alder
adduct 10 is additionally demonstrated and enables us
to direct its subsequent reactivity. Finally, this work serves to
demonstrate the potential for naphthazarin as a building block in
the synthesis of novel organic electronic materials.