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Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
A density functional study towards substituent effects on anion sensing with urea receptors
Amrita Ghosh1, D Amilan Jose, Amitava Das
1Central Salt and Marine Chemicals Research Institute (CSIR), Bhavnagar, 364002, Gujarat, India.
Journal of Molecular Modeling
|February 18, 2010
Summary
Substituent effects on urea receptors reveal altered anion binding preferences. Fluoride binding is stronger in vacuum, but acetate binding is preferred in water, impacting deprotonation sites.
Area of Science:
- Computational Chemistry
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Urea-based receptors are crucial in molecular recognition and sensing.
- Understanding substituent effects is key to designing selective anion binders.
Purpose of the Study:
- To investigate how substituents influence anion binding in urea receptors.
- To compare binding affinities for fluoride and acetate anions in different environments.
- To analyze the impact of substituents on deprotonation sites.
Main Methods:
- Density Functional Theory (DFT) calculations using the B3LYP/6-311+G** level of theory.
- Calculation of binding energies for urea-receptor/anion complexes.
- Determination of pKa values to predict deprotonation sites.
Main Results:
- Receptors showed stronger binding with fluoride than acetate in vacuum.
- Anion binding preference reversed in aqueous environments, favoring acetate.
- Substituent position significantly altered preferred deprotonation sites compared to pKa predictions.
Conclusions:
- Substituents play a critical role in modulating anion binding affinity and selectivity in urea receptors.
- Environmental factors (e.g., solvent) drastically influence binding preferences.
- Computational methods accurately predict substituent effects on receptor behavior and deprotonation characteristics.
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