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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Counterion-induced translational isomerism in a bistable [2]rotaxane
Bo W Laursen1, Sune Nygaard, Jan O Jeppesen
1California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.
Abstract:
Translational isomerization can be induced by changing the anions associated with a bistable rotaxane in which the tetracationic cyclophane (blue box), cyclobis(paraquat-p-phenylene), encircles a dumbbell component containing bispyrrolotetrathiafulvalene (green) and a dioxynaphthalene (red) recognition sites. The rotaxane was isolated as both its hexafluorophosphate and tris(tetrachlorobenzenediolato)phosphate(v) (TRISPHAT(-)) salts. Photophysical measurements and NMR spectroscopy carried out in acetone (CD(3)COCD(3)) and acetonitrile (CD(3)CN) solutions reveal that the much larger TRISPHAT(-) anion favors predominantly the encirclement of the green site by the blue box.
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