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Stabilisation of a heptamethine cyanine dye by rotaxane encapsulation
C M Simon Yau1, Sofia I Pascu, Susan A Odom
1Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, UK OX1 3TA.
Abstract:
The crystal structure of a cyanine dye rotaxane shows that the cyclodextrin is tightly threaded round the polymethine bridge of the dye; encapsulation dramatically increases the kinetic chemical stability of the radicals formed on oxidation and reduction of the dye, making it possible to observe the rotaxane radical dication by ESR and UV-vis-NIR spectroscopy.
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