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Hydrogen bonding is crucial in biological systems but challenging to replicate in synthetic receptors operating in water due to solvent competition. This minireview highlights recent advances in the design of synthetic hydrogen-bonding receptors that function effectively in water. By employing strategies like hydrophobicityassisted hydrogen bonding, charge-assisted interactions, and dynamic covalent chemistry, researchers have developed effective approaches to synthesizing hydrogen-bonding receptors with enhanced affinity and selectivity for hydrophilic substrates. These innovations not only overcome the traditional hurdles of aqueous molecular recognition but also open new avenues in environmental monitoring, biomedical diagnostics, and materials science. The progress underscores the potential of these receptors to drive significant advancements in molecular recognition within aqueous media.
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Charge-assisted hydrogen bonding in a bicyclic amide cage: an effective approach to anion recognition and catalysis in water
Hydrogen bonding is prevalent in biological systems, dictating a myriad of life-sustaining functions in aqueous environments. Leveraging hydrogen bonding for molecular recognition in water encounters significant challenges in synthetic receptors on account of the hydration of their functional groups. Herein, we introduce a water-soluble hydrogen bonding cage, synthesized via a dynamic approach, exhibiting remarkable affinities and selectivities for strongly hydrated anions, including sulfate and oxalate, in water. We illustrate the use of charge-assisted hydrogen bonding in amide-type synthetic receptors, offering a general molecular design principle that applies to a wide range of amide receptors for molecular recognition in water. This strategy not only revalidates the functions of hydrogen bonding but also facilitates the effective recognition of hydrophilic anions in water. We further demonstrate an unconventional catalytic mechanism through the encapsulation of the anionic oxalate substrate by the cationic cage, which effectively inverts the charges associated with the substrate and overcomes electrostatic repulsions to facilitate its oxidation by the anionic MnO4–. Technical applications using this receptor are envisioned across various technical applications, including anion sensing, separation, catalysis, medical interventions, and molecular nanotechnology.
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- Award ID(s):
- 2337419
- PAR ID:
- 10612811
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 15
- Issue:
- 39
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 16040 to 16049
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D4SC05236F
