Recent advances and future challenges in the bottom-up synthesis of azulene-embedded nanographenes.

Abstract

In recent years, significant progress has been made in the synthesis of various nanographenes incorporating non-benzenoid rings, expanding the scope of molecular design beyond all-hexagon polycyclic aromatic hydrocarbons (PAHs). Among these, π-conjugated scaffolds featuring embedded azulene units have gained considerable attention due to their unique optical and electronic properties. This review provides an overview of representative azulene-embedded nanographenes, with a particular focus on the synthetic strategies. Additionally, it explores selected aspects of aromaticity and spectroscopic properties.