Controlled molecular motions in copper-complexed rotaxanes: an XAS study
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Published on: March 13, 2019
J M Kern1, L Raehm, J P Sauvage
1Laboratoire de Chimie Organo-Minérale, UMR 7513 du CNRS, Faculté de Chimie, Université Louis Pasteur, 4 rue Blaise Pascal, 67070 Strasbourg, France.
Abstract:
The environment of the central metal of a molecular machine-like copper rotaxane was observed by XAS experiments. The wheel of the rotaxane is a hetero-bischelating macrocycle containing both bidentate (phenanthroline) and terdentate (terpyridine) moieties. The axle of the assembly contains only a bidentate moiety. Applying an external chemical stimulus-oxidation of the metal-increases the number of coordinating atoms required by the metal template from 4 to 5. This variation is consistent with the oscillation of the wheel around the axle, leading thus to the most stable environment for the metal in the Cu(II) rotaxane.
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