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09:46
Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Anion recognition by hydrogen bonding: urea-based receptors
Valeria Amendola1, Luigi Fabbrizzi, Lorenzo Mosca
1Dipartimento di Chimica Generale, Università di Pavia, 27100 Pavia, Italy.
Chemical Society Reviews
|September 7, 2010
Summary
Urea derivatives are effective anion receptors due to their polarized N-H groups, enabling chelation or hydrogen bonding. Their simple synthesis makes them widely applicable in designing neutral anion receptors.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Analytical Chemistry
Background:
- Urea derivatives have been synthesized since 1992 for anion recognition.
- Anion receptors are crucial in various chemical and biological processes.
- Understanding receptor-anion interactions is key to designing selective binding agents.
Purpose of the Study:
- To review distinctive aspects of anion recognition by urea derivatives.
- To focus on design, synthesis, and solution-phase investigation methodologies.
- To interpret solution behavior based on structural receptor-anion interplay.
Main Methods:
- Review of literature on urea-based anion receptors.
- Analysis of synthetic strategies for urea derivatives.
- Examination of solution-phase techniques for studying receptor-anion interactions.
Main Results:
- Urea's efficiency as a receptor relies on two proximate polarized N-H fragments.
- These fragments facilitate anion chelation or hydrogen bonding with oxoanions.
- Urea's facile synthesis via amine and isocyanate reactions allows high-yield derivative preparation.
Conclusions:
- Urea is a versatile subunit for neutral anion receptor design.
- Its structural features enable effective anion binding through chelation or hydrogen bonding.
- The ease of synthesis contributes to its widespread use in supramolecular chemistry.
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