Abstract 5, 14-α-Diketopentacene, a structural isomer of 6, 13-α-diketopentacene, was prepared from pentacene in three steps. In addition to the typical n–π* absorption of the diketone moiety at around 468 nm and the anthracene-like absorption at 333, 349, and 367 nm, a broad absorption was observed at around 386 nm, which could be assigned to an intramolecular charge-transfer absorption from anthracene to the diketone moiety. 5, 14-α- ...