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Updated: Jun 5, 2026
08:40
Light-driven Molecular Motors on Surfaces for Single Molecular Imaging
Published on: March 13, 2019
A light-powered stretch-contraction supramolecular system based on cobalt coordinated [1]rotaxane
Chao Gao1, Xiang Ma, Qiong Zhang
1Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science & Technology, Meilong Road 130, Shanghai 200237, P. R. China.
Organic & Biomolecular Chemistry
|December 25, 2010
Summary
Researchers developed a light-driven molecular machine using a bistable rotaxane. This mechanically switchable system, featuring azobenzene-modified cyclodextrins and a Schiff base, offers repeatable light-powered transformations.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Molecular Machines
Background:
- Rotaxanes are molecular assemblies with a dumbbell-shaped molecule threaded through a macrocycle.
- Azobenzene derivatives are known for their photoresponsive properties, enabling light-induced structural changes.
- Schiff base linkages and metallosalen units are commonly used in constructing complex molecular architectures.
Purpose of the Study:
- To design and synthesize a mechanically switchable bistable [1]rotaxane.
- To investigate the light-induced movement and conformational changes within the rotaxane system.
- To explore the potential of this rotaxane as a light-driven molecular machine.
Main Methods:
- Synthesis of azobenzene-modified cyclodextrins and Schiff base bridged by a metallosalen unit.
- Characterization using (1)H NOESY NMR and Induced Circular Dichroism (ICD) spectroscopy.
- Computational geometry optimization of the rotaxane before and after UV light irradiation.
Main Results:
- Successful design and synthesis of a bistable [1]rotaxane.
- Spectroscopic evidence (NMR, ICD) confirmed the stretch-contraction movement upon UV irradiation.
- Coordination with cobalt(III) ion increased the rigidity and linearity of the rotaxane, enhancing spectral signals.
- The light-powered rotaxane demonstrated favorable repeatability.
Conclusions:
- The developed [1]rotaxane functions as a mechanically switchable, light-driven molecular machine.
- The system exhibits robust repeatability, making it suitable for molecular device applications.
- This work presents a novel approach for controlling molecular transformations using light energy.
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