Redox Triggers Guest Release and Uptake Across a Series of Azopyridine‐Based Metal–Organic Capsules

Abstract

Precise control over guest release and recapture using external stimuli is a valuable goal, potentially enabling new modes of chemical purification. Including redox moieties within the ligand cores of molecular capsules to trigger the release and uptake of guests has proved effective, but this technique is limited to certain capsules and guests. Herein, we demonstrated the construction of a series of novel metal‐organic capsules from ditopic, tritopic and tetratopic ligands respectively, which contain redox‐active azo groups coordinated to FeII centers. Compared to their iminopyridine‐based analogs, this new class of azopyridine‐based capsule possess larger cavities, capable of encapsulating more voluminous guests. Upon reduction of the capsules, their guests are released and may then be re‐encapsulated when the capsules are regenerated by oxidation. Since the redox centers are on the ligand arms, they are modular and can be attached to a variety of ligand cores to afford varying and predictable architectures. Our method thus shows promise as a generalized approach for designing redox‐controlled guest release and uptake systems.This article is protected by copyright. All rights reserved

Encapsulated Dye in Coordination-Assembled Octahedron for Visible-Light-Driven Proton Reduction and Nitroaromatic Hydrogenation

“…28−30 The spacing between the two adjacent cobalt ions and the two opposite cobalt ions in the octahedron are 14.27 and 20.18 Å, respectively. The inner space of the Co-XLQ octahedron is calculated to be about 2700 Å 3 , and the triangular window side is about 14.3 Å long. The structural features of the molecular octahedron likely allow Fl to be encapsulated in its pocket, photocatalyzing the reduction of proton and nitroaromatic compounds.…”

“…Metal–organic polyhedrons (MOPs) assembled from tunable metal ions and functional ligands have been considered as promising candidates to mimic natural metalloenzymes, due to their facile synthesis, precisely controlled topology, significant solubility and durability in conventional solvents. − These coordination containers with large cavities were employed as supramolecular hosts and have shown remarkable properties on efficiently binding substrates, stabilizing reactive intermediates, and catalyzing chemical transformations, arising from the confinement effect based on their isolated microenvironment. , …”