Photoconversion of a protonated diarylethene derivative
Huan-huan Liu1, Xu Zhang, Zeng Gao
1Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
The Journal of Physical Chemistry. A
|September 20, 2012
Summary
A novel photochromic diarylethene (1a) undergoes reversible photoisomerization. Protonation yields a hydrophobic form (1aH) that converts to a hydrophilic, photoinactive isomer (1c) under UV light.
Area of Science:
- Organic Chemistry
- Photochemistry
- Materials Science
Background:
- Diarylethenes are photochromic compounds known for reversible isomerizations.
- Photochromic materials are crucial for optical data storage and smart devices.
- Controlling hydrophilicity/hydrophobicity is key for applications in responsive systems.
Purpose of the Study:
- To synthesize and characterize a novel N,N-dimethyl substituted photochromic diarylethene (1a).
- To investigate the photoisomerization behavior of the diarylethene and its protonated form.
- To explore the influence of protonation on the photochromic properties and hydrophobicity.
Main Methods:
- Synthesis of diarylethene derivative 1a.
- UV/vis light irradiation for photoisomerization studies.
- Protonation using trifluoroacetic acid (CF3COOH).
- Characterization of hydrophilicity/hydrophobicity of isomers.
Main Results:
- Diarylethene 1a exhibited reversible ring-opening and ring-closing photoisomerization upon UV/vis irradiation.
- Protonation of 1a with CF3COOH yielded the protonated diarylethene 1aH.
- UV irradiation of 1aH led to a photoinactive protonated ring-closed isomer 1c.
- A distinct difference in hydrophilicity was observed: 1c is hydrophilic, while 1aH is hydrophobic.
Conclusions:
- The N,N-dimethyl substituted diarylethene 1a demonstrates tunable photochromism.
- Protonation significantly alters the photochromic and surface properties of the diarylethene.
- The observed switch between hydrophobic and hydrophilic states has potential for responsive material applications.
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