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Triarylborane-Modified Aza[7]helicenes Featuring Two-Photon Absorption and Dual-State Circularly Polarized
Run-Ze Wang1, Zhi-Qiang Liu2, Min Wang3
1School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
Organic Letters
|February 19, 2026
Summary
Two novel borylphenyl-substituted aza[7]helicenes exhibit dual circularly polarized luminescence (CPL) and two-photon absorption (TPA) properties. These findings advance the development of advanced optical materials for potential applications in optoelectronics.
Area of Science:
- Organic Chemistry
- Materials Science
- Photophysics
Background:
- Azahelicenes are a class of chiral aromatic compounds with unique photophysical properties.
- Developing molecules with integrated circularly polarized luminescence (CPL) and two-photon absorption (TPA) is crucial for advanced optical applications.
Purpose of the Study:
- To synthesize and characterize novel borylphenyl-substituted aza[7]helicenes.
- To investigate the CPL and TPA properties of these new molecular architectures.
- To explore the potential of these molecules in optoelectronic devices.
Main Methods:
- Synthesis of borylphenyl-substituted aza[7]helicenes.
- Spectroscopic analysis including CPL and TPA measurements.
- Photoluminescence quantum yield (ΦF) determination in various media (solution, doped film, neat film).
Main Results:
- Two borylphenyl-substituted aza[7]helicenes were successfully synthesized.
- Both molecules exhibited strong CPL with high fluorescence quantum yields (ΦF = 0.15-0.99) across different states.
- Significant TPA properties were observed, with the quadrupolar derivative reaching δTPA = 329 GM.
Conclusions:
- The synthesized aza[7]helicenes possess dual CPL and TPA functionalities.
- These molecules represent rare examples of integrated dual-state CPL and TPA properties.
- The enhanced charge transfer features and optical properties suggest potential for applications in chiral optoelectronics and photonics.
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