Electron-Deficient Polycyclic π-System Fused with Multiple B←N Coordinate Bonds.

Area of Science:

• Organic Chemistry
• Materials Science
• Organic Electronics

Background:

• Developing novel polycyclic π-systems is crucial for advanced organic electronic applications.
• Achieving rigid, planar structures in large π-systems remains a synthetic challenge.

Purpose of the Study:

• To synthesize an extensive polycyclic π-system with 23 fused rings.
• To explore the utility of a novel borylation reaction for constructing rigid molecular architectures.
• To develop new n-type conjugated materials for organic electronics and photovoltaics.

Main Methods:

• A one-pot borylation reaction was employed to synthesize the polycyclic π-system.
• The reaction forms both B-N covalent and B←N coordinate bonds.
• Characterization of the resulting molecule's structure and electronic properties.

Main Results:

• Successfully synthesized a 23-fused-ring polycyclic π-system.
• The borylation reaction efficiently formed four B-N covalent and four B←N coordinate bonds in one pot.
• B←N coordinate bonds induced a near-coplanar conformation and lowered the LUMO energy level to -3.82 eV.

Conclusions:

• The developed borylation strategy is highly effective for synthesizing extensive rigid polycyclic molecules.
• This approach facilitates the creation of n-type conjugated materials with potential applications in organic electronics and photovoltaics.
• The dual role of B←N coordinate bonds in structural control and electronic tuning was demonstrated.