Syntheses and Substituent Effects on the Properties of Unsymmetrical Photochromic Diarylethenes Bearing a Benzothiophene Unit

Shouzhi Pu; Min Li; Gang Liu; Zhanggao Le

doi:10.1071/CH08289

RESEARCH ARTICLE

Previous Next Contents Vol 62(5)

Syntheses and Substituent Effects on the Properties of Unsymmetrical Photochromic Diarylethenes Bearing a Benzothiophene Unit

Shouzhi Pu ^A ^B ^C , Min Li ^A ^B , Gang Liu ^A and Zhanggao Le ^B

+ Author Affiliations

- Author Affiliations

^A Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science & Technology Normal University, Nanchang 330013, China.

^B Key Laboratory of Nuclear Resources and Environment of Ministry of Education, East China Institute of Technology, Fuzhou 344000, China.

^C Corresponding author. Email: pushouzhi@tsinghua.org.cn

Australian Journal of Chemistry 62(5) 464-474 https://doi.org/10.1071/CH08289
Submitted: 8 July 2008 Accepted: 20 March 2009 Published: 15 May 2009

Abstract

Photochromic unsymmetrical diarylethenes 1a–5a that bear different electron-donating or electron-withdrawing substitutes have been synthesized, and the structures of 2a–5a determined by single-crystal X-ray diffraction analysis. Substituent effects on their optoelectronic properties, including photochromism, fluorescence, and electrochemical properties are investigated in detail. The strong electron-donating substituents have effective contributions to the absorption maxima of the closed-ring isomers and the molar coefficients, whereas the electron-withdrawing substituents can shift significantly the absorption maxima of the diarylethenes to a longer wavelength and increase their cyclization quantum yield. Diarylethenes 2, 3, and 4 show good photochromism both in solution and in the single crystalline phase. However, diarylethenes 5 shows no photochromism in the crystalline phase. Diarylethenes 1, 2, and 3 exhibit good fluorescent switching upon alternating irradiation with UV and visible light, and their fluorescent conversions in the photostationary state are all larger than 80% in hexane. In addition, cyclic voltammogram tests show that different electron-donating and electron-withdrawing substituents have a remarkable effect on the electrochemical behaviours of these diarylethenes.

Acknowledgements

This work was supported by the Program for New Century Excellent Talents in University (NCET-08–0702), the Project of Jiangxi Youth Scientist, National Natural Science Foundation of Jiangxi Province (2008GZH0020), the Key Scientific Project from Education Ministry of China (208069) and the Science Funds of the Education Office of Jiangxi, China (GJJ08365).

References

Syntheses and Substituent Effects on the Properties of Unsymmetrical Photochromic Diarylethenes Bearing a Benzothiophene Unit

Abstract

Acknowledgements

Subscriber Login