title: Tuning redox chemistry and photophysics in core-substituted tetraazaperopyrenes (TAPPs).
abstract: Core substitution of tetraazaperopyrenes (TAPPs) has been achieved, and with it, considerable variation of their photo- and redox-chemical properties. Through Suzuki cross coupling starting from the fourfold core-brominated tetraazaperopyrene, aryl-substituted TAPPs were synthesized, which displayed very high fluorescence quantum yields (up to 100 %) in solution. Besides the Suzuki reactions, Stille and Sonogashira cross-couplings were also found to be suitable methods for core derivatization, as demonstrated in the syntheses of alkynyl-substituted tetraazaperopyrene congeners. Furthermore, TAPPs incorporating intramolecular donor-acceptor combinations of aromatic units (8, 9) were accessible by coupling the electron-poor peropyrene core with electron-rich aromatic units, which act as strong electron donors. Finally, C-heteroatom coupling (O, S, N) gave rise to novel TAPP derivatives with strongly modified redox-chemical behaviour and photophysics in the solid state as well in solution. In particular, TAPP derivatives displaying red fluorescence were obtained for the first time.
authors.affiliation: Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg (Germany), Fax: (+49) 6221-545609.
authors.forename: Sonja
authors.initials: S
authors.lastname: Geib
authors.forename: Susanne C
authors.initials: SC
authors.lastname: Martens
authors.forename: Michaela
authors.initials: M
authors.lastname: Märken
authors.forename: Arina
authors.initials: A
authors.lastname: Rybina
authors.forename: Hubert
authors.initials: H
authors.lastname: Wadepohl
authors.forename: Lutz H
authors.initials: LH
authors.lastname: Gade
keywords: electrochemistry; electron transfer; fluorescence; photophysics; redox chemistry