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Lighting Up Rotaxanes with Tunable and Switchable Circularly Polarized Luminescence
1School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China.
Accounts of Chemical Research
|November 24, 2025
Summary
Researchers developed novel chiral rotaxanes, which are mechanically interlocked molecules, to create advanced materials with tunable circularly polarized luminescence (CPL). These rotaxanes offer precise control over CPL properties for applications in smart devices and sensors.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Organic Chemistry
Background:
- Mechanically interlocked molecules (MIMs), specifically rotaxanes, possess unique structures and controllable dynamic behaviors due to mechanical bonds.
- Rotaxanes are utilized in artificial molecular machines and have applications in sensing, drug delivery, and catalysis.
- There is a growing interest in luminescent rotaxanes, particularly those exhibiting circularly polarized luminescence (CPL), for advanced optical materials.
Purpose of the Study:
- To design and synthesize novel chiral rotaxanes with tunable and switchable circularly polarized luminescence (CPL) properties.
- To investigate the role of mechanical bonds in enhancing CPL performance.
- To explore the potential of rotaxanes in developing advanced CPL-active materials and smart devices.
Main Methods:
- Rational design and synthesis of chiral rotaxanes incorporating luminogens.
- Synthesis and characterization of mechano-stereoisomers (static and dynamic) of rotaxanes.
- Development of rotaxane-branched dendrimers with multiple chiral rotaxane units.
- Investigation of light-harvesting properties in rotaxane-based systems.
Main Results:
- Successful synthesis of a series of CPL-active rotaxanes with precisely arranged luminogens.
- Confirmation that mechanical bonds enhance the CPL performance of chiral pillar[5]arene wheels within rotaxanes.
- Demonstration of precise tuning and switching of CPL performances (handedness, wavelength, PLQY, glum) through mechano-stereoisomers.
- Observation of generation-dependent CPL performance in rotaxane-branched dendrimers with enhanced CPL via sequential light harvesting.
Conclusions:
- Rotaxanes are promising platforms for designing and constructing novel CPL emitters with tunable and switchable properties.
- The unique mechanical bonds in rotaxanes play a crucial role in modulating CPL performance.
- These findings provide a foundation for developing advanced smart chiral luminescent materials for diverse applications.
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