Highly Deformed o-Carborane Functionalised Non-linear Polycyclic Aromatics with Exceptionally Long C-C Bonds
Adam V Marsh1, Mark Little1, Nathan J Cheetham2
1Department of Chemistry and Centre for Processable Electronics, Imperial College London, London, SW7 2AZ, UK.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 12, 2020
Summary
Researchers synthesized novel carborane-functionalised non-linear acenes, revealing unique structural distortions and aggregation-induced emission properties. These findings advance the understanding of carborane chemistry and luminescent materials.
Area of Science:
- Organic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Carboranes are unique boron-containing clusters with diverse applications.
- Non-linear acenes are polycyclic aromatic hydrocarbons with interesting electronic and optical properties.
- Functionalizing acenes with carboranes can lead to novel materials with tailored characteristics.
Purpose of the Study:
- To synthesize and characterize novel carborane-functionalised non-linear acenes.
- To investigate the structural and photoluminescent properties of these new compounds.
- To explore potential applications in areas like organic electronics and sensing.
Main Methods:
- Synthesis of carborane-substituted phenanthrene and benzo(k)tetraphene via Bull-Hutchings-Quayle benzannulation.
- X-ray crystallography to determine crystal structures and analyze aromatic deformation.
- Photoluminescence spectroscopy to study intramolecular charge-transfer and emission properties.
Main Results:
- The synthesized compounds exhibited significant aromatic deformation, setting new records for carborane compounds.
- Unusually long carboranyl C-C bond lengths were observed in the organo-substituted carboranes.
- Efficient intramolecular charge-transfer and aggregation-induced emission (AIE) properties were demonstrated.
- An uncommon low-energy excimer was detected in the phenanthryl derivative.
Conclusions:
- Two new carborane-functionalised non-linear acenes with unique structural and luminescent characteristics have been successfully synthesized.
- These compounds showcase high aromatic deformation and promising AIE properties, driven by intramolecular charge-transfer.
- The observed structural and photophysical behaviors suggest potential for these materials in advanced optical and electronic applications.
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