Synthesis new photochromic diarylethenes 1-(2,5-dimethyl thiazole)-2-[4-(2-cyanophenyl)-3-thienyl]} perfluorocyclopentene

A unsymmetrical photochromic diarylethene, 1-(2,5-dimethyl thiazole)-2-[4-(2-cyanophenyl)-3-thienyl]} perfluorocyclopentene(1a),was synthesized, and its optoelectronic properties were also investigated in detail. The results showed that this compound exhibited reversible photochromism, changing from colorless to orange red after irradiation with UV light both in solution and in PMMA amorphous film. The open-ring isomer of the diarylethene 1 exhibited relatively strong fluorescence at 432 nm when excited at 384 nm. The fluorescence intensity declined along with the photochromism upon irradiation with 297 nm light. The diarylethene exhibited a fluorescence switches along with the photochromism from open-ring isomers to closed-ring isomers. When irradiated by UV light, the photocyclization reaction was occurred and the emission intensity of the diarylethene decreased significantly, due to producing the non-fluorescence closed-ring isomers. The back irradiation by appropriate wavelength visible light regenerated its open-ring isomers and recovered the original emission intensity.