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Title: Photoswitchable Sol–Gel Transitions and Catalysis Mediated by Polymer Networks with Coumarin‐Decorated Cu 24 L 24 Metal–Organic Cages as Junctions
Abstract

Photoresponsive materials that change in response to light have been studied for a range of applications. These materials are often metastable during irradiation, returning to their pre‐irradiated state after removal of the light source. Herein, we report a polymer gel comprising poly(ethylene glycol) star polymers linked by Cu24L24metal–organic cages/polyhedra (MOCs) with coumarin ligands. In the presence of UV light, a photosensitizer, and a hydrogen donor, this “polyMOC” material can be reversibly switched between CuII, CuI, and Cu0. The instability of the MOC junctions in the CuIand Cu0states leads to network disassembly, forming CuI/Cu0solutions, respectively, that are stable until re‐oxidation to CuIIand supramolecular gelation. This reversible disassembly of the polyMOC network can occur in the presence of a fixed covalent second network generated in situ by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC), providing interpenetrating supramolecular and covalent networks.

 
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PAR ID:
10131070
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
132
Issue:
7
ISSN:
0044-8249
Page Range / eLocation ID:
p. 2806-2814
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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