Efficient Synthesis, Photochromism and Fluorescence Properties of a Novel Diarylethene Bearing a Fluorene

A new symmetrical photochromic diarylethene, 1,2-bis-[2-methyl-5-(9,9-dibutyl-9H-fluorene) -3-thienyl] perfluorocyclopentene (1a), was synthesized and its optoelectronic properties, such as photochromism in solution and fluorescence were investigated. The photochromic reaction kinetics indicated that the cyclization processes of 1a belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction. The new diarylethene also exhibited relatively strong fluorescence by photoirradiation in solution and the fluorescence intensity decreased along with the photochromism upon irradiation 297 nm light and its closed-ring isomer showed almost no fluorescence.