Photochromism and the fluorescence properties of bisbenzothienylethene and S,S,S′,S′-tetraoxide derivatives with dual conjugated fluorescent groups on their side chains

Two photochromic bisbenzothienylethenes with two fluorescent (4-((2,5-bis(dodecyloxy)-4-(phenylethynyl)phenyl)ethynyl)phenyl) units and their disulfone derivatives were synthesized, and their photochromic and fluorescence properties were examined. Bisbenzothienylethenes showed photochromism and turn-off type fluorescence by UV-light irradiation, while their disulfone derivatives showed turn-on type fluorescence and the one-way isomerization to the closed form.