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Phenazine-Based Oligomers as Redox-Responsive Molecular Actuators
Jingwei Yin1, Vladimir B Birman1
1Washington University Department of Chemistry, Campus Box 1134, One Brookings Drive, Saint Louis, Missouri 63130, United States.
The Journal of Organic Chemistry
|November 10, 2022
Summary
Nanosized foldamers with alternating phenazine and terephthalamide units exhibit reversible extension-contraction. This response to oxidation state changes is achievable through both chemical and electrochemical methods, offering a clean and repeatable process.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Nanotechnology
Background:
- Foldamers are polymers that mimic protein secondary structures.
- Controlling foldamer conformation is crucial for developing responsive materials.
- Butterfly-coil foldamers offer unique structural properties.
Purpose of the Study:
- To investigate the responsive behavior of nanosized butterfly-coil foldamers.
- To explore the use of oxidation state changes to control foldamer conformation.
- To assess the reversibility and cleanliness of the conformational change process.
Main Methods:
- Synthesis of foldamers with alternating phenazine-1,6-dicarboxamide and 2,5-dialkoxyterephthalamide moieties.
- Induction of conformational changes via chemical methods (catalytic hydrogenation/aerial oxidation).
- Induction of conformational changes via electrochemical methods.
Main Results:
- Nanosized butterfly-coil foldamers demonstrated extension-contraction behavior.
- Conformational changes were directly linked to alterations in the oxidation state of the foldamer.
- Both chemical and electrochemical methods proved effective in inducing and reversing the conformational changes.
- The process was characterized as clean and fully reversible.
Conclusions:
- Butterfly-coil foldamers can be designed to exhibit tunable conformational dynamics.
- Oxidation state modulation provides a viable mechanism for controlling foldamer structure at the nanoscale.
- The reversible nature of these foldamers opens possibilities for applications in molecular machines and responsive nanomaterials.
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