title: Triazole bridges as versatile linkers in electron donor-acceptor conjugates.
abstract: Aromatic triazoles have been frequently used as π-conjugated linkers in intramolecular electron transfer processes. To gain a deeper understanding of the electron-mediating function of triazoles, we have synthesized a family of new triazole-based electron donor-acceptor conjugates. We have connected zinc(II)porphyrins and fullerenes through a central triazole moiety--(ZnP-Tri-C(60))--each with a single change in their connection through the linker. An extensive photophysical and computational investigation reveals that the electron transfer dynamics--charge separation and charge recombination--in the different ZnP-Tri-C(60) conjugates reflect a significant influence of the connectivity at the triazole linker. Except for the m4m-ZnP-Tri-C(60)17, the conjugates exhibit through-bond photoinduced electron transfer with varying rate constants. Since the through-bond distance is nearly the same for all the synthesized ZnP-Tri-C(60) conjugates, the variation in charge separation and charge recombination dynamics is mainly associated with the electronic properties of the conjugates, including orbital energies, electron affinity, and the energies of the excited states. The changes of the electronic couplings are, in turn, a consequence of the different connectivity patterns at the triazole moieties.
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
authors.forename: Gustavo
authors.initials: G
authors.lastname: de Miguel
authors.forename: Mateusz
authors.initials: M
authors.lastname: Wielopolski
authors.forename: David I
authors.initials: DI
authors.lastname: Schuster
authors.forename: Michael A
authors.initials: MA
authors.lastname: Fazio
authors.forename: Olivia P
authors.initials: OP
authors.lastname: Lee
authors.forename: Christopher K
authors.initials: CK
authors.lastname: Haley
authors.forename: Angy L
authors.initials: AL
authors.lastname: Ortiz
authors.forename: Luis
authors.initials: L
authors.lastname: Echegoyen
authors.forename: Timothy
authors.initials: T
authors.lastname: Clark
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Guldi
mesh_terms: D003432:Cross-Linking Reagents / Q000737:chemistry; D004583:Electrons; D037741:Fullerenes / Q000737:chemistry; D008665:Metalloporphyrins / Q000737:chemistry; D014230:Triazoles / Q000737:chemistry*
chemical_list: D003432:Cross-Linking Reagents; D037741:Fullerenes; D008665:Metalloporphyrins; D014230:Triazoles; C017802:zinc hematoporphyrin