Study on Composite Properties of a Novel Unsymmetrical Diarylethene with Benzene Unit

A novel photochromic diarylethene 1-{[2-methyl-5-formyl-3-thienyl]}-2-[2-methyl-5-(4-cyanophenyl)-3- thienyl]perfluorocyclopentene(1a) has been synthesized for the examination of its properties including photochromism， fluorescence properties and optical recording. Diarylethene 1a changed the color from colorless to cadet blue upon irradiation with 297 nm UV light, in which absorption maxima were observed at 600 nm in hexane and at 610 nm in PMMA film, respectively. The open-ring isomer of the diarylethene 1 exhibited good fluorescence switch in hexane solution. In hexane solution, the open-ring isomer of the diarylethene 1a exhibited relatively fluorescence at 383 nm when excited at 310 nm.