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Updated: Jan 15, 2026
09:35
Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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A Rational Framework to Estimate the Chiroptical Activity of [6]Helicene Derivatives
Mirko Vanzan1, Susanna Bertuletti2, Giacomo Becatti1
1Department of Physics, University of Milan, Via Celoria 16, 20133 Milan, Italy.
The Journal of Physical Chemistry. A
|October 6, 2025
Summary
Researchers explored how chemical modifications affect helicenes
Area of Science:
- Organic Chemistry
- Physical Chemistry
- Materials Science
Background:
- Helicenes possess intrinsic structural chirality and intense chiroptical properties, making them promising for technological applications.
- Chiroptical property estimation for helicenes is crucial for their application but remains challenging.
Purpose of the Study:
- To investigate the influence of substituents on the chiroptical properties of [6]helicene.
- To establish a framework for fine-tuning helicene properties through chemical modification.
Main Methods:
- Combined experimental optical characterization and ab initio calculations.
- Systematically varied substituents (size, chemical nature) on the [6]helicene core.
Main Results:
- Both electron-withdrawing and electron-donating substituents red-shifted and diminished the optical activity.
- Observed changes in transition energy and intensity are linked to substituent-induced perturbations on π-conjugation.
Conclusions:
- Substituent modification offers a viable strategy for tailoring helicenes' chiroptical properties.
- This study provides insights for designing novel helicene-based materials with specific optical characteristics.
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