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Published on: April 27, 2017
Anion binding vs. sulfonamide deprotonation in functionalised ureas
Claudia Caltagirone1, Gareth W Bates, Philip A Gale
1School of Chemistry, University of Southampton, Southampton, UK.
Chemical Communications (Cambridge, England)
|April 11, 2008
Summary
Sulfonamide groups in urea-based anion receptors can lose protons when interacting with basic anions. This deprotonation behavior is observed in simple functionalized ureas, impacting receptor design.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Sulfonamide groups are frequently employed as neutral hydrogen bond donors in anion receptor design.
- Anion receptors play a crucial role in molecular recognition and sensing applications.
Purpose of the Study:
- To investigate the deprotonation behavior of sulfonamide groups within functionalized urea-based anion receptors.
- To understand the interaction between basic anionic guests and sulfonamide hydrogen bond donors.
Main Methods:
- Synthesis of two simple functionalized urea derivatives containing sulfonamide groups.
- Titration experiments with various basic anionic guests to monitor deprotonation.
Main Results:
- Observed deprotonation of sulfonamide groups upon addition of specific basic anionic guests.
- Demonstrated that functionalized ureas can undergo sulfonamide deprotonation, unlike typical neutral hydrogen bond donors.
Conclusions:
- The study reveals a novel deprotonation mechanism for sulfonamide groups in urea-based anion receptors.
- Findings provide insights for designing anion receptors with tunable acidity and enhanced binding.
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