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Hierarchical Chirality Memory Governs Dual Chiroptical Inversion in Mesoscopic Helical Covalent Organic Frameworks
Zhenzhen Jiang1, Xinlin Zha1, Mengjuan Zuo1
1Key Laboratory of Textile Fiber and Products, Ministry of Education, Wuhan Textile University, Wuhan, China.
Angewandte Chemie (International Ed. in English)
|August 7, 2026
Summary
Researchers developed a dynamic covalent evolution strategy to create crystalline chiral covalent organic frameworks (CCOFs) with tunable chiroptical properties. This method allows for programmable control over optical responses in advanced materials.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Crystalline chiral covalent organic frameworks (CCOFs) with tunable chiroptical properties are difficult to synthesize.
- Controlling chirality and optical responses from a single chiral source is a significant challenge in materials science.
Purpose of the Study:
- To develop a dynamic covalent evolution strategy for constructing mesoscopic helical CCOFs.
- To achieve programmable chiroptical properties and explore novel inversion modes in CCOFs.
- To demonstrate the versatility of the strategy using a single chiral template system.
Main Methods:
- Dynamic covalent evolution strategy.
- Thermodynamic self-crystallization.
- Monomer exchange (single-step and stepwise).
- Time-dependent experiments and theoretical calculations.
- Pore-confined incorporation of guests.
Main Results:
- Transformed helical polymers into mesoscopic helical CCOFs.
- Observed two distinct chiroptical inversion modes (conventional and packing-dependent).
- Demonstrated persistent chirality- and packing-memory effects during dynamic reconstruction.
- Synthesized 24 mesoscopic helical CCOFs with diverse chemistries and programmable responses.
- Extended inversion modes to circularly polarized luminescence films.
Conclusions:
- The dynamic covalent evolution strategy enables the construction of CCOFs with programmable chiroptical properties.
- The study reveals novel chiroptical inversion mechanisms related to sub-nanometer chiral packing.
- This approach offers a versatile platform for designing advanced chiral materials with tailored optical functionalities.
Keywords:
chiral covalent organic frameworkschiral packingchirality memorychiroptical inversiondynamic covalent reconstructionMore Related Videos
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