Spontaneous Assembly of Rotaxanes From a Primary Amine, Crown Ether and Electrophile

Research output: Contribution to journalArticle

  • Authors:
  • Stephen Fielden
  • David Leigh
  • Charlie McTernan
  • Borja Perez-Saavedra
  • Inigo Vitorica-Yrezabal


We report the synthesis of crown ether-ammonium, amide and amine [2]rotaxanes via transition state stabilization of axle-forming reactions. In contrast to the two-step “clipping” and “capping” strategies generally used for rotaxane synthesis, here the components assemble into the interlocked molecule in a single, reagent-less, step under kinetic control. The crown ether accelerates the reaction of the axle-forming components through the cavity to give the threaded product in a form of metal-free active template synthesis. Rotaxane formation can proceed through the stabilization of different transition states featuring 5-coordinate (e.g., SN2) or 4-coordinate (e.g., acylation, Michael addition) carbon. Examples prepared using the approach include crown-ether-peptide rotaxanes and switchable molecular shuttles.

Bibliographical metadata

Original languageEnglish
Pages (from-to)6049-6052
JournalJournal of the American Chemical Society
Issue number19
Early online date2 May 2018
Publication statusPublished - 16 May 2018

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