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Assembling Molecular Shuttles Powered by Reversibly Attached Kinesins
Published on: January 26, 2019
Fluorescence control of boron enaminoketonate using a rotaxane shuttle
Yasuhito Koyama1, Tohru Matsumura, Tatsuto Yui
1Catalysis Research Center, Hokkaido University , N21 W10, Kita-ku, Sapporo 001-0021, Japan, Department of Organic and Polymeric Materials, Tokyo Institute of Technology , 2-12-1 (H-126), Ookayama, Meguro, Tokyo 152-8552, Japan, Department of Material Science and Technology, Faculty of Engineering, Niigata University , Igarashi 2-8050, Niigata 950-2181, Japan, and Department of Chemistry, Tokyo Institute of Technology , 2-12-1 (E1-9), Ookayama, Meguro, Tokyo 152-8551, Japan.
Abstract:
The effect of rotaxane shuttling on the fluorescence properties of a fluorophore was investigated by exploiting fluorophore-tethered [2]rotaxanes. A fluorescent boron enaminoketonate (BEK) moiety was introduced in a rotaxane via transformation of an isoxazole unit generated as a result of an end-capping reaction using a nitrile N-oxide. The rotaxane exhibited a red shift of the fluorescence maximum along with a remarkable enhancement of the fluorescence quantum yield through wheel translation to the fluorophore.
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