title: Polyphenylene dendrimers with perylene diimide as a luminescent core.
abstract: A novel synthesis is presented of a fourfold ethynyl-substituted perylene diimide dye 4, which acts as a core molecule for the buildup of polyphenylene dendrimers. Around the luminescent core 4, a first-generation (5), a second-generation (6), and a third-generation (7) polyphenylene dendritic environment consisting of pentaphenylbenzene building blocks are constructed. The dendrimers 5 and 6 are synthesized by an exclusively divergent route, whereas for 7, a combination of a divergent and convergent approaches is applied. Absorption and emission spectra of 5-7 in different solvents and in a film have been measured and compared to a nondendronized model compound 13. In solution, the internal chromophore is scarcely influenced by the dendritic scaffold; however, in the solid state, aggregation of the perylene diimide is prevented very effectively by the four rigid dendrons. Additionally, fluorescence quantum yields in solution have been determined for 5-7 and 13; they decrease as the number of generation increases.
authors.affiliation: Max-Planck-Institute for Polymer Research, Mainz, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Herrmann
authors.forename: T
authors.initials: T
authors.lastname: Weil
authors.forename: V
authors.initials: V
authors.lastname: Sinigersky
authors.forename: U M
authors.initials: UM
authors.lastname: Wiesler
authors.forename: T
authors.initials: T
authors.lastname: Vosch
authors.forename: J
authors.initials: J
authors.lastname: Hofkens
authors.forename: F C
authors.initials: FC
authors.lastname: De Schryver
authors.forename: K
authors.initials: K
authors.lastname: Müllen