Photo-switchable anion binding and catalysis with a visible light responsive halogen bonding receptor
Aidan Kerckhoffs1, Isabelle Moss1, Matthew J Langton1
1Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK. matthew.langton@chem.ox.ac.uk.
Chemical Communications (Cambridge, England)
|November 28, 2022
Summary
Researchers developed novel photo-switchable anion receptors for precise control over guest binding using light. These receptors enable light-modulated catalysis, enhancing chloride binding affinity by over 50-fold.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Photochemistry
Background:
- Photo-switchable receptors offer precise spatial and temporal control over molecular interactions.
- Halogen bonding (XB) is a key non-covalent interaction utilized in molecular recognition.
Purpose of the Study:
- To develop the first halogen bonding photo-switchable anion receptors.
- To investigate the reversible modulation of chloride binding using red and blue light.
- To demonstrate photo-controlled catalysis mediated by these switchable receptors.
Main Methods:
- Synthesis of novel photo-switchable halogen bonding receptors.
- Spectroscopic and binding studies to quantify chloride affinity.
- Photochemical irradiation with visible light (red and blue).
- Catalytic assays for halide abstraction and Mukaiyama Aldol reactions.
Main Results:
- Demonstrated reversible photo-modulation of chloride binding affinity.
- Achieved over a 50-fold enhancement in chloride binding for the Z-isomer upon irradiation.
- Successfully employed the switchable receptors for photo-controlled catalysis.
Conclusions:
- The developed receptors represent a new class of photo-switchable anion binders.
- Light-induced control over halogen bonding enables precise catalytic applications.
- This work opens avenues for light-responsive supramolecular systems and catalysis.
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