Photochromic behavior of 2,3-bis(2,5-dimethylthiophene-3-yl)thiophene-5-carbaldehyde oxime

ABSTRACT

Photochromic diarylethene oxime isomers were obtained by coupling between hydroxylamine hydrochloride and 2,3-bis(2,5-dimethylthiophene-3-yl)thiophene-5-carbaldehyde. The two isomers were confirmed by NMR. Photochromic behavior was investigated in THF. Reversible photochromism could be induced by alternated UV/Visible light. The solution color also can be toggled between colorless and light purple. Corresponding photo- and thermo-stability measurements indicate that they are stable in the dark at room temperature. However, the degradation of the two isomers is accelerated with the temperature rising and prolonged exposure to UV light. Optimized geometry structure and frontier molecular orbitals further supported their photochromic activity.

KEYWORDS:

• Diarylethene oxime
• frontier molecular orbitals
• photochromism
• photo-thermo-stability

Funding

This work was supported by the National Natural Science Foundation of China (21072048), and the Program for Innovative Research Team in University of Henan Province (15IRTSTHN003). This study was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (Grant no. NRF-2014M3C1A9060739).