Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition

Halogen bonding (XB), the interaction between electron deficient halogen compounds and electron donors, is an established non-covalent interaction in the solid and gaseous phases. Understanding of XB in the solution phase is limited. This thesis describes experimental studies of XB interactions in s...

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Main Author: Sarwar, Md. Golam
Other Authors: Mark, Taylor
Language:en_ca
Published: 2012
Subjects:
Online Access:http://hdl.handle.net/1807/34876
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spelling ndltd-LACETR-oai-collectionscanada.gc.ca-OTU.1807-348762013-04-17T04:19:48ZThermodynamic Studies of Halogen Bonding in Solution and Application to Anion RecognitionSarwar, Md. GolamHalogen bondinganion receptorsolvent effectmolecular recognitionhalide receptormesitylene0490Halogen bonding (XB), the interaction between electron deficient halogen compounds and electron donors, is an established non-covalent interaction in the solid and gaseous phases. Understanding of XB in the solution phase is limited. This thesis describes experimental studies of XB interactions in solution, and the application of XB interactions in anion recognition. Chapter 1 is a brief review of current understanding of XB interaction: theoretical models, studies of XB in solid and gaseous phases and examples in biological systems are discussed. At the end of this chapter, halogen bonding in the solution phase is discussed, along with applications of halogen bonding in organic syntheses. In chapter 2, linear free energy relationships involving the thermodynamics of halogen bonding of substituted iodoaromatics are studied. The utility of substituent constants and calculated molecular electrostatic potential values as metrics of halogen bond donor ability are discussed. Density Functional Theory (DFT) calculations are shown to have useful predictive values for trends in halogen bond strength for a range of donor-acceptor pairs. Chapter 3 describes the development of new multidentate anion receptors based on halogen bonding. Bidentate and tridentate receptors were found to exhibit significantly higher binding constants than simple monodentate donors. These receptors show selectivity for halide anions over oxyanions. Using 19F NMR spectra at different temperature, the enthalpies and entropies of anion bindings for monodentate and tridentate receptors were determined. The results indicate a positive entropy contribution to anion binding for both mono and tridentate receptors in acetone solvent. Finally in chapter 4, some mesitylene based receptors with 3-halopyridinium and 2-iodobenzimidazolium donors are introduced. The receptors perform halide anion recognition in aqueous solvent system through charge-assisted XB interactions. These findings can allude to utility in organic synthesis, supramolecular chemistry and drug design.Mark, Taylor2012-112012-12-19T19:03:39ZNO_RESTRICTION2012-12-19T19:03:39Z2012-12-19Thesishttp://hdl.handle.net/1807/34876en_ca
collection NDLTD
language en_ca
sources NDLTD
topic Halogen bonding
anion receptor
solvent effect
molecular recognition
halide receptor
mesitylene
0490
spellingShingle Halogen bonding
anion receptor
solvent effect
molecular recognition
halide receptor
mesitylene
0490
Sarwar, Md. Golam
Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition
description Halogen bonding (XB), the interaction between electron deficient halogen compounds and electron donors, is an established non-covalent interaction in the solid and gaseous phases. Understanding of XB in the solution phase is limited. This thesis describes experimental studies of XB interactions in solution, and the application of XB interactions in anion recognition. Chapter 1 is a brief review of current understanding of XB interaction: theoretical models, studies of XB in solid and gaseous phases and examples in biological systems are discussed. At the end of this chapter, halogen bonding in the solution phase is discussed, along with applications of halogen bonding in organic syntheses. In chapter 2, linear free energy relationships involving the thermodynamics of halogen bonding of substituted iodoaromatics are studied. The utility of substituent constants and calculated molecular electrostatic potential values as metrics of halogen bond donor ability are discussed. Density Functional Theory (DFT) calculations are shown to have useful predictive values for trends in halogen bond strength for a range of donor-acceptor pairs. Chapter 3 describes the development of new multidentate anion receptors based on halogen bonding. Bidentate and tridentate receptors were found to exhibit significantly higher binding constants than simple monodentate donors. These receptors show selectivity for halide anions over oxyanions. Using 19F NMR spectra at different temperature, the enthalpies and entropies of anion bindings for monodentate and tridentate receptors were determined. The results indicate a positive entropy contribution to anion binding for both mono and tridentate receptors in acetone solvent. Finally in chapter 4, some mesitylene based receptors with 3-halopyridinium and 2-iodobenzimidazolium donors are introduced. The receptors perform halide anion recognition in aqueous solvent system through charge-assisted XB interactions. These findings can allude to utility in organic synthesis, supramolecular chemistry and drug design.
author2 Mark, Taylor
author_facet Mark, Taylor
Sarwar, Md. Golam
author Sarwar, Md. Golam
author_sort Sarwar, Md. Golam
title Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition
title_short Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition
title_full Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition
title_fullStr Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition
title_full_unstemmed Thermodynamic Studies of Halogen Bonding in Solution and Application to Anion Recognition
title_sort thermodynamic studies of halogen bonding in solution and application to anion recognition
publishDate 2012
url http://hdl.handle.net/1807/34876
work_keys_str_mv AT sarwarmdgolam thermodynamicstudiesofhalogenbondinginsolutionandapplicationtoanionrecognition
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