TY  - JOUR
A1  - Merz, Julia
A1  - Dietz, Maximilian
A1  - Vonhausen, Yvonne
A1  - Wöber, Frederik
A1  - Friedrich, Alexandra
A1  - Sieh, Daniel
A1  - Krummenacher, Ivo
A1  - Braunschweig, Holger
A1  - Moos, Michael
A1  - Holzapfel, Marco
A1  - Lambert, Christoph
A1  - Marder, Todd  B.
T1  - Synthesis, Photophysical and Electronic Properties of New Red-to-NIR Emitting Donor-Acceptor Pyrene Derivatives
JF  - Chemistry - A European Journal
N2  - We synthesized new pyrene derivatives with strong bis(para ‐methoxyphenyl)amine donors at the 2,7‐positions and n ‐azaacene acceptors at the K‐region of pyrene. The compounds possess a strong intramolecular charge transfer, leading to unusual properties such as emission in the red to NIR region (700 nm), which has not been reported before for monomeric pyrenes. Detailed photophysical studies reveal very long intrinsic lifetimes of >100 ns for the new compounds, which is typical for 2,7‐substituted pyrenes but not for K‐region substituted pyrenes. The incorporation of strong donors and acceptors leads to very low reduction and oxidation potentials, and spectroelectrochemical studies show that the compounds are on the borderline between localized Robin‐Day class‐II and delocalized Robin‐Day class‐III species.
KW  - orylation
KW  - K-region
KW  - luminescence
KW  - polycyclic aromatic hydrocarbons
KW  - redox
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-207486
VL  - 26
IS  - 2
ER  - 
TY  - JOUR
A1  - Liu, Bin
A1  - Vonhausen, Yvonne
A1  - Schulz, Alexander
A1  - Höbartner, Claudia
A1  - Würthner, Frank
T1  - Peptide Backbone Directed Self-Assembly of Merocyanine Oligomers into Duplex Structures
JF  - Angewandte Chemie International Edition
N2  - The pseudopeptide backbone provided by N-(2-aminoethyl)-glycine oligomers with attached nucleobases has been widely utilized in peptide nucleic acids (PNAs) as DNA mimics. Here we demonstrate the suitability of this backbone for the formation of structurally defined dye stacks. Toward this goal a series of peptide merocyanine (PMC) dye oligomers connected to a N-(2-aminoethyl)-glycine backbone were prepared through peptide synthesis. Our concentration-, temperature- and solvent-dependent UV/Vis absorption studies show that under the control of dipole–dipole interactions, smaller-sized oligomers consisting of one, two or three dyes self-assemble into defined duplex structures containing two up to six chromophores. In contrast, upon further extension of the oligomer, the chosen peptide backbone cannot direct the formation of a defined duplex architecture anymore due to intramolecular aggregation between the dyes. For all aggregate species a moderate aggregation-induced emission enhancement is observed.
KW  - dipole-dipole interaction
KW  - peptide backbone
KW  - merocyanine
KW  - dye assembly
KW  - duplex structure
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318797
VL  - 61
IS  - 21
ER  -