Abstract
Classical polycyclic aromatic hydrocarbons (PAHs) are a large group of π-conjugated
planar structures. To explore more properties of PAHs, new structures have been designed,
including some with nonplanar topologies and heteroatom-containing moieties. As important
nanographene (NG) units, hexabenzocoronene (HBC) and its derivatives have been intensively
researched. Many HBC-based nonplanar NGs have been developed, and heteroatom-doped
HBC-based NGs have also been designed and synthesized. Here, we summarize some methods
for the synthesis of HBC-based NGs containing a seven- or eight-membered ring, and
we discuss our newly synthesized NGs containing embedded azepine or azocine moieties,
obtained by a modified synthetic route and a conventional Müllen’s synthetic method,
respectively.
Key words
nanographenes - Diels–Alder reaction - polycyclic aromatic hydrocarbons - hexabenzocoronenes
- azepines - azocines