Synthesis of Aryl-Substituted Hexa-Alkynyl Hexaazatrinaphthylenes via Sonogashira Coupling and Evaluation of Their Photophysical Properties.

Hexaazatrinaphthylene (HATNA) has recently been a subject of great interest as a polycyclic heteroaromatic scaffold in materials science, specifically in the field of discotic liquid crystals (DLCs), battery cathodes, n-type semiconductors, and so on. However, little is known about the photophysical properties of HATNA derivatives. Here we report the synthesis of a new class of hexa(arylethynyl) HATNA derivatives via consecutive Sonogashira coupling. This protocol showed good functional-group tolerance and moderate to good yields were achieved. The obtained HATNA products showed favorable photophysical properties, with molar absorption coefficients up to 1.69 × 105 (M-1 cm-1) and high quantum yields up to 0.73.