Diastereoselective photochromism of bisbenzothienylethenes with an oxycarbonyl-related functional group on the side chain.
Nine 1-[2-(1-substituted)ethyl-3-benzothienyl]-2-(2-methyl-3-benzothienyl)hexafluorocyclopentenes (4-substituted benzoyloxy, N-arylcarbamoyloxy, and aryloxycarbonyloxy) were synthesized. They showed diastereoselective photochromic ring closure upon UV irradiation. Among them, 4-nitrophenoxycarbonyloxy-substituted compound recorded a remarkable 94% diastereomer excess with 91% conversion to the closed form.
Kose
Mahmut
M
Department of Advanced Materials Chemistry, Graduate School of Engineering, Yokohama National University, Hodogaya, Yokohama, 240-8501, Japan.
Shinoura
Miyuki
M
Yokoyama
Yayoi
Y
Yokoyama
Yasushi
Y