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Electron-deficient triphenylene and trinaphthylene carboximides
1Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543.
Organic Letters
|June 25, 2009
Summary
New disk-like molecules, triphenylene and trinaphthylene carboximides, were synthesized. These materials exhibit ordered columnar structures, showing potential as n-type semiconductors for electronic devices.
Area of Science:
- Organic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Triphenylene and trinaphthylene derivatives are known for their unique electronic and self-assembly properties.
- Carboximide functional groups can significantly alter molecular electronic characteristics.
- Diels-Alder reactions are a powerful tool for constructing complex polycyclic aromatic systems.
Purpose of the Study:
- To synthesize novel triphenylene and trinaphthylene carboximides.
- To investigate the impact of electron-withdrawing carboximide groups on molecular properties.
- To characterize the self-assembly behavior and mesophase properties of the synthesized compounds.
Main Methods:
- Diels-Alder reactions utilizing in situ generated radialenes and N-alkylmaleimides.
- Differential Scanning Calorimetry (DSC) for thermal analysis.
- Polarized Optical Microscopy (POM) and X-ray diffraction for structural characterization.
Main Results:
- Successful synthesis of a series of triphenylene and trinaphthylene carboximides.
- Observation of high electron affinity due to the incorporated carboximide groups.
- Formation of one-dimensional columnar structures in the solid state with long-range order.
Conclusions:
- The synthesized carboximide derivatives exhibit well-defined mesophase properties.
- The observed long-range ordered columnar phase makes these molecules promising candidates for n-type semiconductor applications.
- This study expands the library of discotic liquid crystals with potential in organic electronics.
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