A light-driven metallo-supramolecular "claw-machine"

Abstract: The incorporation of light-responsive moieties into ligand architectures allows for the synthesis of adaptive metal-organic cages. These structures demonstrate potential for applications as molecular transporters, switchable catalysts, and smart materials.[1] This work investigates the potential of photo-responsive M2L3 helicates as a light-controlled ‘claw machine’ for selectively grabbing a metal ion. The structure self-assembles into a closed state with the diazocine photoswitch in its bent cis ground state. Upon irradiation, the photoswitch transitions into a metastable and linear trans configuration, inducing strain and weakening the metal-ligand bonds. This metastable state exhibits a much faster exchange rate in the metal replacement process. When the irradiation ceases, thermal relaxation or irradiation with white light results in the structure reverting to its original state. Like a claw machine, the helicate offers spatiotemporal control over the metal cation replacement process which is not easily achieved using stimuli other than light.

1. E. Benchimol, J. Tessarolo and G. H. Clever, Nat. Chem., 2024, 16, 13–21.

materials chemistrynanoscienceorganic chemistryphysical chemistrysupramolecular chemistryadaptation and self-organizing systems

Audience: researchers in the topic

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