A Dual Functional Molecular Tweezer: pH-Driven C60 Capture/Release and Ba2+ Selective Recognition
Yixing He1, Zhi Yu1, Selina X Yao2
1College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China.
Organic Letters
|August 8, 2025
Summary
New molecular tweezers based on resorcinarenes can reversibly bind C60 fullerenes. These tweezers also act as sensors for barium ions, showcasing a bifunctional molecular architecture for advanced applications.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Materials Science
Background:
- Resorcinarene macrocycles are versatile platforms for molecular recognition.
- Crown ethers are known for their cation-binding properties.
- Fullerene encapsulation presents challenges in host-guest chemistry.
Purpose of the Study:
- To synthesize novel resorcinarene-based molecular tweezers.
- To investigate their pH-responsive conformational changes.
- To explore their capability for fullerene encapsulation and ion sensing.
Main Methods:
- Synthesis of resorcinarene macrocycles functionalized with benzo-crown-ether moieties.
- pH-dependent conformational analysis (vase and kite forms).
- Spectroscopic studies for fullerene binding and barium ion detection.
Main Results:
- Successful synthesis of dual benzo-crown-ether functionalized resorcinarene tweezers.
- Demonstrated pH-responsive switching between vase and kite conformations.
- Reversible C60 fullerene encapsulation under basic conditions via dispersion forces.
- Acid-triggered release of encapsulated C60.
- Selective fluorescence sensing of barium ions by one derivative.
Conclusions:
- The synthesized macrocycles are pH-responsive and can encapsulate C60.
- One derivative exhibits bifunctional behavior: fullerene recognition and barium ion sensing.
- This work presents a novel molecular architecture for integrated host-guest and ion-sensing applications.
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