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Benzopyrano-Fused Phenanthridine-Based Columnar Mesogens: Synthesis, Self-organization and Charge-Transport
Vanishree Bhat S1, Marichandran Vadivel1, Dharmendra Pratap Singh2
1Soft Condensed Matter group, Raman Research Institute, C. V. Raman Avenue, Bangalore, 560080, India.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|March 1, 2023
Summary
Novel nitrogen and oxygen-containing dimers exhibit excellent thermal stability and self-organization. These chromenonaphthophenanthridine materials show promising ambipolar charge transport for organic electronics.
Area of Science:
- Supramolecular chemistry
- Organic electronics
- Materials science
Background:
- Columnar mesogens are supramolecular nano-architectures with unique properties due to self-assembly.
- Incorporating heteroatoms into π-conjugated systems influences mesomorphic and photophysical properties, making them suitable for optoelectronics.
Purpose of the Study:
- To synthesize novel nitrogen and oxygen-incorporated chromenonaphthophenanthridine-based elliptical dimers.
- To investigate their mesomorphic, photophysical, and charge transport properties for potential optoelectronic applications.
Main Methods:
- Synthesis via tandem Pictet-Spengler cyclization and ipso-aromatic substitution.
- Mesophase characterization using polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction.
- Photophysical analysis via UV-vis and emission spectroscopy.
- Charge transport evaluation using time-of-flight measurements.
Main Results:
- Successful synthesis of novel elliptical dimers.
- Demonstrated liquid crystalline behavior and excellent thermal stability.
- Achieved ambipolar charge transport with mobilities of approximately 10^-3 cm^2 V^-1 s^-1.
- High solubility and self-organizing properties were observed.
Conclusions:
- The synthesized chromenonaphthophenanthridine dimers possess favorable properties for organic electronics.
- Their ambipolar charge transport and thermal stability make them promising for optoelectronic devices.
- Further research into these materials could advance organic electronic applications.
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