Synthesis of a New Unsymmetrical Photochromic Diarylethene for Rewritable Holographic Optical Storage

A new photochromic diarylethene, 1-(2-methyl-5-toluene-3-thienyl)-2-[2-methyl-5-(4-fluorophenyl)-3-thienyl]- perfluorocyclopentene (1a), was synthesized and its photochromic and fluorescent properties were investigated. Diarylethene 1a changed the color from colorless to blue upon irradiation with 313 nm UV light, in which absorption maxima were observed at 575 nm in hexane and at 584 nm in PMMA amorphous film, respectively. This new photochromic system also exhibited remarkable fluorescence intensity both in solution and in PMMA film. Finally, rewritable holographic optical storage using 1a was performed. The results demonstrated that the compound was very sensitive responding to 633 nm recording laser, and the recorded holographic images have good contrast.