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Synthesis of a pH-Sensitive Hetero[4]Rotaxane Molecular Machine that Combines [c2]Daisy and [2]Rotaxane Arrangements
Philip Waelès1, Benjamin Riss-Yaw1, Frédéric Coutrot2
1Supramolecular Machines and ARchitectures Team, Institut des Biomolécules Max Mousseron (IBMM) UMR 5247 CNRS, Université Montpellier, ENSCM, case courrier 1706, Bâtiment Chimie (17), 3ème étage, Faculté des Sciences, Place Eugène Bataillon, 34095, Montpellier cedex 5, France.
Abstract:
The synthesis of a novel pH-sensitive hetero[4]rotaxane molecular machine through a self-sorting strategy is reported. The original tetra-interlocked molecular architecture combines a [c2]daisy chain scaffold linked to two [2]rotaxane units. Actuation of the system through pH variation is possible thanks to the specific interactions of the dibenzo-24-crown-8 (DB24C8) macrocycles for ammonium, anilinium, and triazolium molecular stations. Selective deprotonation of the anilinium moieties triggers shuttling of the unsubstituted DB24C8 along the [2]rotaxane units.
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