Oligoindenopyrenes: a new class of polycyclic aromatics
Hermann A Wegner1, Helge Reisch, Karsten Rauch
1Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany.
The Journal of Organic Chemistry
|November 18, 2006
Summary
Researchers synthesized novel oligoindenopyrenes, a new class of polycyclic aromatic hydrocarbons. These robust, colored compounds show potential for organic materials and devices due to efficient deactivation pathways.
Area of Science:
- Organic Chemistry
- Materials Science
- Photophysics
Background:
- Polycyclic aromatic hydrocarbons (PAHs) are crucial in organic electronics.
- Developing novel PAHs with tailored properties is essential for advanced materials.
- Understanding photophysical processes in complex aromatic systems is key for device applications.
Purpose of the Study:
- To synthesize a new class of polycyclic aromatic hydrocarbons: oligoindenopyrenes.
- To investigate the structural and photophysical properties of these novel compounds.
- To explore their potential applications in organic materials and devices.
Main Methods:
- Synthesis of oligoindenopyrenes via a palladium-catalyzed Suzuki-Heck coupling cascade.
- Characterization of the synthesized compounds, including structural and optical properties.
- Photophysical measurements, including deactivation pathways, fluorescence quantum yield, and fluorescence decay time.
Main Results:
- Successful synthesis of oligoindenopyrenes, robust and highly colored molecules.
- Oligoindenopyrenes exhibit properties relevant to C(70) substructures.
- Tetraindenopyrene derivative 3d shows highly efficient deactivation (99%) via internal conversion, with a low fluorescence quantum yield (0.004) and short fluorescence decay time (0.6 ns).
Conclusions:
- Oligoindenopyrenes represent a new, synthetically accessible class of PAHs.
- Their robust nature and unique optical properties suggest potential for new organic materials.
- Efficient non-radiative decay pathways in tetraindenopyrene derivatives are confirmed, impacting their luminescent behavior for potential device applications.
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