title: Dibenzo[a,f]perylene bisimide: effects of introducing two fused rings.
abstract: Perylene bisimides (PBIs) are fascinating dyes with various potential applications. To study the effects of introducing a dibenzo-fused structure to the perylene moiety, π-extended PBI derivatives with a dibenzo-fused structure at both of the a and f bonds were synthesized. The twisted structure was characterized by X-ray crystal structure analysis. In the cyclic voltammograms, the dibenzo[a,f]-fused PBI showed a reversible oxidation wave at much less positive potential, relative to a dibenzo[a,o]-fused PBI derivative. These data indicated that two ring fusions at both sides of a naphthalene moiety, which construct a tetracene core, effectively raise the HOMO level compared to fusion of one ring at each naphthalene moiety (two anthracene cores). The dibenzo[a,f]-fused PBI derivative showed an absorption band at 735 nm with a shoulder band reaching 900 nm.
authors.affiliation: Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan), Fax: (+81) 774-38-3178.
authors.lastname: Chaolumen
authors.forename: Hiroki
authors.initials: H
authors.lastname: Enno
authors.forename: Michihisa
authors.initials: M
authors.lastname: Murata
authors.forename: Atsushi
authors.initials: A
authors.lastname: Wakamiya
authors.forename: Yasujiro
authors.initials: Y
authors.lastname: Murata
keywords: X-ray analysis; benzannulation; dyes; perylene bisimide; tetracene