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Ribbon-Type Boron-Doped Polycyclic Aromatic Hydrocarbons: Conformations, Dynamic Complexation and Electronic
Wenting Sun1, Jiaxiang Guo1, Zengming Fan1
1State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
Angewandte Chemie (International Ed. in English)
|August 11, 2022
Summary
Researchers developed novel boron-doped molecular ribbons (MRs) using photochemical cyclization. These new boron-doped MRs exhibit photochromism and show potential as organic semiconductors in transistors.
Area of Science:
- Synthetic Chemistry
- Material Science
- Organic Electronics
Background:
- Molecular ribbons (MRs) are 1D topological polycyclic aromatic hydrocarbons (PAHs) crucial for chemistry and materials science.
- Developing novel MR structures with tailored electronic properties remains a key challenge.
Purpose of the Study:
- To synthesize novel boron-doped molecular ribbons (MRs) with extended π-systems.
- To investigate the photophysical properties and potential applications of these new boron-doped MRs.
Main Methods:
- Photochemical cyclization of conjugated organoboranes via Mallory photoreaction in solution.
- Characterization of synthesized boron-doped PAHs, including structural and photophysical analysis.
- Fabrication and testing of organic field-effect transistors (OFETs) using the synthesized materials.
Main Results:
- Successfully synthesized a series of ribbon-type boron-doped PAHs with multiple cove edges.
- Two compounds feature isomeric C68B2 π-skeletons, 2.2 nm in length, representing a new class of boron-doped MRs.
- Boron doping imparts Lewis acidity, leading to photo-induced dual-dissociation behavior and photochromism in adducts.
- Demonstrated potential as organic semiconductors through OFET fabrication, despite contorted conformations.
Conclusions:
- A novel strategy for synthesizing boron-doped molecular ribbons via photochemical cyclization was established.
- The synthesized boron-doped MRs exhibit unique photochromic properties due to Lewis acidity and excited-state dynamics.
- These materials hold promise for applications in organic electronics, particularly as organic semiconductors.
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