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Published on: March 13, 2019
Controlling molecular shuttling in a rotaxane with weak ring recognition sites
Nina Bukhtiiarova1,2, Alberto Credi1,2, Stefano Corra1,2
1CLAN-Center for Light Activated Nanostructures, Istituto per la Sintesi Organica e Fotoreattività, CNR area della ricerca Bologna, via Gobetti, 101, 40129, Bologna, Italy.
Abstract:
We describe a rotaxane molecular shuttle encompassing triazolium and tertiary ammonium units as weak recognition sites for the ring. Such a design, which differs from that of typical controllable rotaxanes, allows the precise tuning of the ring distribution among the two sites - i.e., the coconformational equilibrium - by changing the solvent polarity or the nature of the counteranions. Shuttling of the ring between the two stations can also be toggled by acid-base stimuli. Such an approach is paradigmatic to obtain rotaxanes that can sense environmental changes and transduce them into a coconformational response and opens avenues for novel applications in sensing and stimuli-responsive materials.
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