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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Porphyrin-functionalised rotaxanes for anion recognition
1Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, UK OX1 3QR.
Dalton Transactions (Cambridge, England : 2003)
|November 15, 2011
Summary
Two new porphyrin-functionalized rotaxane hosts selectively bind chloride anions. Electrochemical detection is effective, though optical sensing is not viable for these rotaxane anion sensors.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Analytical Chemistry
Background:
- Porphyrin-based macrocycles are crucial in host-guest chemistry.
- Rotaxanes offer unique structural motifs for molecular recognition.
- Developing selective anion sensors remains a significant challenge.
Purpose of the Study:
- To synthesize novel porphyrin-functionalized [2]rotaxane host molecules.
- To investigate the anion-recognition properties of these rotaxane systems.
- To evaluate their potential as anion sensors.
Main Methods:
- Template-directed synthesis using a clipping strategy.
- Proton Nuclear Magnetic Resonance ((1)H NMR) titration experiments.
- UV-visible spectroscopy, fluorescence spectroscopy, and electrochemical methods.
Main Results:
- Successful synthesis of two new porphyrin-functionalized [2]rotaxanes.
- High binding affinities and general selectivities for chloride anions observed via (1)H NMR.
- Ineffective optical sensing capabilities for chloride anions.
- Electrochemical detection of chloride anions through shifts in porphyrin redox couples.
Conclusions:
- The synthesized rotaxanes are effective chloride anion binders.
- Electrochemical detection offers a viable sensing mechanism for these systems.
- Optical sensing is not suitable for these specific rotaxane receptors.
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