Synthesis and Properties of a Novel Unsymmetrical Diarylethene with Five and Six Ring Aryls

A novel photochromic diarylethene with thiophene and benzene compound, 1-{[2-methyl-5-(1, 3-dioxolane)-3-thienyl]}-2-(2-cyanophenyl)perfluorocyclopentene(1a) has been synthesized. Its photochemical properties, including photochromic behavior and fluorescent features, have been investigated in detail. The compound showed good photochromism both in solution and in PMMA. 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.