The Self-Assembly of a Switchable [2]Rotaxane

Authors

  • Dr. M.-Victoria Martínez-Díaz,

    1. School of chemistry, University of Birmingham Edgbaston, Brimingham B15 2TT (UK) Fax: Int. Code + (121)414-3531
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  • Dr. Neil Spencer,

    1. School of chemistry, University of Birmingham Edgbaston, Brimingham B15 2TT (UK) Fax: Int. Code + (121)414-3531
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  • Prof. J. Fraser Stoddart

    Corresponding author
    1. School of chemistry, University of Birmingham Edgbaston, Brimingham B15 2TT (UK) Fax: Int. Code + (121)414-3531
    • School of chemistry, University of Birmingham Edgbaston, Brimingham B15 2TT (UK) Fax: Int. Code + (121)414-3531
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  • This research was supported by the Ministerial de Education y ienica in Spain in the form of Postdoctoral Fellowship (to m.-V. M.-D). and by the Engineering and Physical Sciences Research Council in the United Kingdom. We thank Peter. Ashton for carrying out the mass spectrometric measurements.

Abstract

original image

A secondary dialkylammonium center and a bipyridinium unit form the two binding sites within the dumbbell-shaped component of a switchable [2]rotaxane. The shuttling of the dibenzo[24]crown-8 ring along the dumbbell so that it interacts either with the ammonium center or with the bipyridinium unit can be controlled by the pH and is reversible (depicted schematically on the right). Deprotonation of the NHmath image center is achieved with diisopropylethylamine, and reprotonation with trifluoroacetic acid.

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