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Controlling molecular shuttling in a rotaxane with weak ring recognition sites.
Nina Bukhtiiarova1,2, Alberto Credi1,2, Stefano Corra1,2
1CLAN-Center for Light Activated Nanostructures, Istituto per la Sintesi Organica e Fotoreattività, CNR area della ricerca Bologna, via Gobetti, 101, 40129, Bologna, Italy.
Chemical Communications (Cambridge, England)
|October 18, 2023
Summary
This study introduces a novel rotaxane molecular shuttle with tunable ring positioning. Environmental changes like solvent polarity and acid-base stimuli precisely control the ring
Area of Science:
- Supramolecular Chemistry
- Materials Science
Background:
- Controllable rotaxanes are essential for molecular machines.
- Precise control over molecular component positioning is challenging.
Purpose of the Study:
- To design and synthesize a rotaxane molecular shuttle with tunable ring distribution.
- To investigate the influence of external stimuli on the rotaxane's conformation.
Main Methods:
- Synthesis of a rotaxane featuring triazolium and tertiary ammonium recognition sites.
- Investigation of ring distribution using varying solvent polarities and counteranions.
- Stimuli-responsive studies using acid-base treatments.
Main Results:
- The rotaxane exhibits tunable ring distribution between two recognition sites.
- Solvent polarity and counteranion identity precisely control the coconformational equilibrium.
- Acid-base stimuli effectively toggle the shuttling motion of the ring.
Conclusions:
- This novel rotaxane design allows for precise control over molecular shuttling.
- The system demonstrates sensitivity to environmental changes, enabling stimuli-responsive behavior.
- Opens new possibilities for rotaxanes in sensing and advanced materials.
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