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arXiv · 2012.08458

Regulation of macrocycle shuttling in [2]rotaxanes by amino-acid speed bumps in organic-aqueous solvent mixtures

Maxime Douarre·Vicente Martí-Centelles·Cybille Rossy·Isabelle Pianet·Nathan D. McClenaghan
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Abstract

A homologous series of two-station [2]rotaxanes incorporating amino-acid units in the molecular thread has been developed. The degenerate [2]rotaxanes exhibit amino-acid specific shuttling rates between two fumaric stations related to the steric factor associated to the amino-acid side chain, as demonstrated by variable-temperature 1H NMR spectroscopy and exchange spectroscopy (EXSY). This allows tuning of the macrocycle shuttling rate over 4 orders of magnitude, which further has a relatively small solvent dependency.

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Maxime Douarre, Vicente Martí-Centelles, Cybille Rossy, Isabelle Pianet, Nathan D. McClenaghan. 2020-12-15. Regulation of macrocycle shuttling in [2]rotaxanes by amino-acid speed bumps in organic-aqueous solvent mixtures. https://doi.org/10.1002/ejoc.202000997

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