Synthesis of Ring-Fused Pyridinium Salts by Intramolecular Nucleophilic Aromatic Substitution Reaction and Their Optoelectronic Properties

The synthesis of nitrogen cation-doped polycyclic aromatic hydrocarbons (PAHs) having a variety of counteranions is reported via the trimethylsilyl (TMS)-promoted intramolecular aromatic nucleophilic substitution (SNAr) reaction of fluoroarenes and pyridine groups. The electrochemical properties and optical properties of the obtained nitrogen cation-doped PAHs were studied in detail, clarifying that they have low-lying LUMO levels and good emission properties derived from the incorporation of planar N-arylpyridinium moieties.