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Self-Assembly-Triggered Cis-to-Trans Conversion of Azobenzene Compounds
Zheng Wu1, Rongrong Xue1, Mengqi Xie1
1Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
The Journal of Physical Chemistry Letters
|December 22, 2017
Summary
Achieve high-purity trans azobenzene compounds. Triggered self-assembly of trans isomers drives cis-to-trans transitions, overcoming limitations of light or thermal methods for azobenzene materials.
Area of Science:
- Photochemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Azobenzene compounds undergo cis-to-trans isomerization via light or thermal relaxation.
- Complete isomerization is challenging due to overlapping electronic transitions of cis and trans isomers.
- Existing methods often yield incomplete cis-to-trans transitions.
Purpose of the Study:
- To develop a novel method for achieving complete cis-to-trans transition in azobenzene compounds.
- To overcome the limitations of conventional photostationary state approaches.
- To enable the synthesis of spectrum-grade pure trans azobenzene isomers.
Main Methods:
- Viewing the photostationary state as a chemical equilibrium.
- Utilizing triggered self-assembly of trans isomers to drive the transition.
- Designing a coordinating azo molecule to facilitate the process.
Main Results:
- Demonstrated that triggered self-assembly effectively promotes cis-to-trans isomerization.
- Achieved spectrum-grade purity of trans azobenzene isomers.
- Established a new paradigm for controlling azobenzene isomerization.
Conclusions:
- Self-assembly offers a powerful strategy for manipulating azobenzene isomerization.
- This approach provides a pathway to highly pure trans azobenzene compounds.
- The findings may inspire the development of advanced azo-based materials.
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