Heptene end-capped Thiele hydrocarbons with tunable configuration and emission and on-surface transformation via annulation

We report a para-quinodimethane skeleton (p-QDM)-based polycyclic aromatic hydrocarbon (PAH) with heptenes as end-capping groups and F-substituents in the central six-membered ring. This compound shows the syn-configuration in one crystal form with relative strong emission (Φ_F = 0.25), and the anti-configuration in another crystal form with weak emission. Furthermore, this compound was transformed into the more annulated PAHs via on-surface C-F bond activations.