Chiroptical Recognition of Carboxylates with Charge-Neutral Double-Stranded Zinc(II) Helicates.
Malavika G Kalarikkal1, Christoph Drechsler1, Gers Tusha2
1Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Straße 6, 44227, Dortmund, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 30, 2023
Summary
This study introduces metal-based helicate probes for enantiopurity analysis using CD spectroscopy. These probes offer a non-invasive, high-throughput method for chiral small molecule recognition.
Area of Science:
- Supramolecular Chemistry
- Analytical Chemistry
- Spectroscopy
Background:
- Chromatographic methods dominate small molecule enantiopurity determination using chiral stationary phases.
- Chiroptical probes, though less common, offer advantages like using standard spectroscopic techniques (e.g., CD spectroscopy) for enantiomer analysis.
- Receptor-based approaches are gaining interest for non-invasive, high-throughput screening with reduced waste.
Purpose of the Study:
- To investigate the use of charge-neutral, metal-based helicate containers as chiroptical probes for anion recognition.
- To explore the potential of triazole-based helicates in distinguishing and quantifying enantiomers of small molecules.
- To demonstrate the chirality analysis of tartrate using this novel receptor-based method.
Main Methods:
- Synthesis of charge-neutral metal-based helicates incorporating triazole units.
- Utilizing circular dichroism (CD) spectroscopy to observe chiroptical responses.
- Investigating the recognition of chiral mono- and dicarboxylate anions by the helicate probes.
- Performing chirality analysis on tartrate as a model chiral analyte.
Main Results:
- Metal-based helicates with triazole units were successfully synthesized, exhibiting conformational flexibility leading to meso or racemic structures.
- A distinct chiroptical response was observed upon the binding of chiral carboxylate anions to the helicate probes.
- The developed system demonstrated the capability for chirality analysis of tartrate.
Conclusions:
- Metal-based helicates can function as effective chiroptical probes for anion recognition and chirality analysis.
- This receptor-based approach provides a viable alternative to traditional chromatographic methods for determining enantiopurity.
- The study highlights the potential for developing advanced, non-invasive analytical tools for chiral molecule analysis.
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