Related Experiment Video
Updated: May 16, 2025
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
8.0K
Hierarchical chirality conversion switched by biaxial halogen bonding
Weilong Ma1, Zhaozhen Cao1, Na Zhang1
1Key Laboratory of Colloid and Interface Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University Jinan 250100 People's Republic of China nzhang@sdu.edu.cn xingpengyao@sdu.edu.cn.
Chemical Science
|April 14, 2025
Summary
Researchers controlled molecular and supramolecular chirality in peptides using halogen bonds. This work enables dynamic manipulation of chiroptical properties in peptide-based materials.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Organic Chemistry
Background:
- Peptide-based materials offer tunable properties for advanced applications.
- Controlling chirality at multiple levels (molecular and supramolecular) is key for chiroptical materials.
- Biaxial halogen bonds are emerging as precise tools for molecular assembly control.
Purpose of the Study:
- To demonstrate controlled conversion between folded molecular chirality and supramolecular chirality in peptides.
- To investigate the switching mechanism of chirality using biaxial halogen bonds.
- To inspire the design of novel peptide-based chiroptical materials.
Main Methods:
- Conjugation of amino acid segments to a bipyridine core to form β-turns and promote β-sheet arrays.
- Intramolecular chirality transfer to appended pyrenes for chiroptical signal generation.
- Self-assembly into nanohelices and subsequent disruption/rearrangement using hypervalent iodine(III) species via biaxial halogen bonds.
Main Results:
- Achieved efficient excimer emission and boosted circularly polarized luminescence (dissymmetry factor up to 10⁻²).
- Demonstrated self-assembly into nanohelices with solvent-mediated supramolecular chirality.
- Showcased the suppression of supramolecular chirality and recovery of molecular chirality through biaxial halogen bonding, enabling dynamic chiroptical manipulation.
Conclusions:
- Developed a method for dynamic control over hierarchical chirality in peptides.
- Established biaxial halogen bonds as effective switches for supramolecular chirality.
- Opened new avenues for designing responsive peptide- and protein-based chiroptical materials.
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