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Published on: July 17, 2020
Efficient oxidative cycloreversion reaction of photochromic dithiazolythiazole
Takuya Nakashima1, Yoshiyuki Kajiki, Sayo Fukumoto
1Graduate School of Materials Science, Nara Institute of Science and Technology, NAIST, Ikoma, Nara 630-0192, Japan.
Journal of the American Chemical Society
|November 21, 2012
Summary
Photochromic diarylethenes undergo an electrochemical ring-opening reaction with 900% current efficiency. This process involves a chain reaction mechanism facilitated by long-lived radical cation intermediates.
Area of Science:
- Electrochemistry
- Organic Chemistry
- Photochemistry
Background:
- Photochromic diarylethenes are organic molecules that change color upon light exposure.
- Understanding their electrochemical properties is crucial for developing advanced materials.
Purpose of the Study:
- To investigate the electrochemical behavior of photochromic diarylethenes.
- To elucidate the mechanism of the electrochemical oxidative ring-cycloreversion reaction.
Main Methods:
- Cyclic voltammetry
- Density Functional Theory (DFT) calculations
- Spectroelectrochemistry
- Electron transfer stopped-flow study
Main Results:
- 4,5-Bis(2-phenyl-5-methylthiazolyl)-2-phenylthiazole exhibits an electrochemical oxidative ring-cycloreversion reaction.
- A high net current efficiency of 900% was achieved, attributed to local-cell and chain reaction mechanisms.
- Radical cation intermediates of both closed- and open-ring isomers were identified, with the open-ring isomer's radical cation having a lifetime of 33 seconds.
Conclusions:
- The study reveals a novel electrochemical oxidative ring-cycloreversion pathway in photochromic diarylethenes.
- The high efficiency is driven by a unique chain reaction involving long-lived radical cation intermediates.
- Findings provide insights into the electrochemistry of photochromic systems for potential applications.
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