Light-Fueled Transformations of a Dynamic Cage-Based Molecular System

Marco Ovalle, Michael Kathan*, Ryojun Toyoda, Charlotte N. Stindt, Stefano Crespi, Ben L. Feringa*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

12 Citations (Scopus)
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In a chemical equilibrium, the formation of high-energy species—in a closed system—is inefficient due to microscopic reversibility. Here, we demonstrate how this restriction can be circumvented by coupling a dynamic equilibrium to a light-induced E/Z isomerization of an azobenzene imine cage. The stable E-cage resists intermolecular imine exchange reactions that would “open” it. Upon switching, the strained Z-cage isomers undergo imine exchange spontaneously, thus opening the cage. Subsequent isomerization of the Z-open compounds yields a high-energy, kinetically trapped E-open species, which cannot be efficiently obtained from the initial E-cage, thus shifting an imine equilibrium energetically uphill in a closed system. Upon heating, the nucleophile is displaced back into solution and an opening/closing cycle is completed by regenerating the stable all-E-cage. Using this principle, a light-induced cage-to-cage transformation is performed by the addition of a ditopic aldehyde.

Original languageEnglish
Article numbere202214495
Number of pages10
JournalAngewandte Chemie - International Edition
Issue number9
Publication statusPublished - 20-Feb-2023


  • Dynamic Covalent Chemistry
  • Molecular Machines
  • Photoswitches
  • Self-Assembly
  • Out-Of-Equilibrium Chemistry

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