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Paul D. Beer - One of the best experts on this subject based on the ideXlab platform.
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Cationic all-halogen bonding rotaxanes for Halide Anion recognition
Faraday discussions, 2017Co-Authors: Jason Y. C. Lim, Paul D. BeerAbstract:A family of cationic halogen bonding [2]rotaxanes have been synthesised via an active-metal template synthetic strategy. 1H NMR spectroscopic Anion titration investigations reveal these interlocked host systems recognize Halides selectively over oxoAnions in aqueous–organic solvent media. Furthermore, systematically modulating the rigidity and size of the rotaxanes’ Anion binding cavities via metal complexation, as well as by varying the number of halogen bond-donor groups in the axle component, was found to dramatically influence Halide Anion selectivity.
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Strong and Selective Halide Anion Binding by Neutral Halogen-Bonding [2]Rotaxanes in Wet Organic Solvents.
Chemistry (Weinheim an der Bergstrasse Germany), 2017Co-Authors: Jason Y. C. Lim, Thanthapatra Bunchuay, Paul D. BeerAbstract:The design and construction of neutral interlocked host molecules for Anion recognition are rare. Using an active-metal template approach, the preparation of a family of neutral halogen bonding (XB) rotaxanes containing two, three and four iodotriazole groups integrated into the macrocycle and axle components is achieved. In spite of the interlocked hosts' neutrality, such rotaxane systems are capable of binding Halide Anions strongly and selectively in wet organic solvent mixtures. Importantly, Halide-binding strength and selectivity can be modulated by varying the number and position of the halogen bond donor iodotriazole groups within the interlocked cavity; the rotaxane containing the largest number of halogen bond donor groups exhibits the highest Halide Anion-binding affinities. By varying the percentage of water content in the solvent, neutral XB donor-mediated Anion-binding strength is also demonstrated to be highly sensitive to solvent polarity.
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halogen bonding enhanced electrochemical Halide Anion sensing by redox active ferrocene receptors
Chemical Communications, 2015Co-Authors: Jason Y. C. Lim, Matthew J Cunningham, Jason J Davis, Paul D. BeerAbstract:The first examples of halogen bonding redox-active ferrocene receptors and their Anion electrochemical sensing properties are reported. Halogen bonding was found to significantly amplify the magnitude of the receptor's metallocene redox-couple's voltammetric responses for Halide sensing compared to their hydrogen bonding analogues in both acetonitrile and aqueous–acetonitrile solvent media.
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halogen and hydrogen bonding catenanes for Halide Anion recognition
Chemistry: A European Journal, 2014Co-Authors: Lydia C Gilday, Paul D. BeerAbstract:Halogen-bonding (XB) interactions were exploited in the solution-phase assembly of Anion-templated pseudorotaxanes between an isophthalamide-containing macrocycle and bromo- or iodo-functionalised pyridinium threading components. (1)H NMR spectroscopic titration investigations demonstrated that such XB interpenetrated assemblies are more stable than analogous hydrogen bonding (HB) pseudorotaxanes. The stability of the Anion-templated halogen-bonded pseudorotaxane architectures was exploited in the preparation of new halogen-bonding interlocked catenane species through a Grubbs' ring-closing metathesis (RCM) clipping methodology. The catenanes' Anion recognition properties in the competitive CDCl(3)/CD(3) OD 1:1 solvent mixture revealed selectivity for the heavier Halides iodide and bromide over chloride and acetate.
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A ferrocene imidazolium-based macrocycle as an electrochemical chemosensor for Halide Anions
CrystEngComm, 2014Co-Authors: Antonio Caballero, Nicholas G. White, Paul D. BeerAbstract:C4-H and C5-H protons of the imidazolium heterocycle have been exploited as a binding site for Anion recognition in the design of two new redox-active imidazoliophane syn and anti isomers. The cooperative action of the two imidazolium motifs of the syn isomer is crucial for Halide Anion recognition. The integration of a ferrocene signalling unit at the C2 position of the imidazolium motif also facilitates the electrochemical sensing of Anions by the syn isomer receptor.
Jonathan L Sessler - One of the best experts on this subject based on the ideXlab platform.
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controlling structure beyond the initial coordination sphere complexation induced reversed micelle formation in calix 4 pyrrole containing diblock copolymers
Journal of the American Chemical Society, 2018Co-Authors: Xiaodong Chi, Jonathan L Sessler, Vincent M. Lynch, Gretchen Marie Peters, Chandler BrockmanAbstract:A diblock copolymer containing a strapped calix[4]pyrrole-based ion pair recognition subunit has been synthesized via RAFT polymerization. As prepared, the polymer is hydrophobic and devoid of any particular morphological form. However, upon ion pair complexation, the copolymer self-assembles to generate reverse micelles in organic media. The reverse micelles formed in this way may be used to extract alkali cation and cesium Halide Anion salts from an aqueous source into an organic receiving phase. The polymer proved more effective as an extractant than the corresponding free ion pair receptor.
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poly methyl methacrylate copolymers containing dipyrrolylquinoxaline receptors for the colorimetric detection of Halide Anion salts
Supramolecular Chemistry, 2012Co-Authors: Eric S Silver, Christopher W. Bielawski, Brett M Rambo, Jonathan L SesslerAbstract:Described herein is the synthesis of a dipyrrolylquinoxaline (DPQ) monomeric species containing methacrylamide functionality, and its subsequent copolymerisation with methyl methacrylate (MMA). The resulting copolymers were drop casted onto glass substrates, and the resulting thin films displayed distinct colorimetric change upon exposure to hydrofluoric acid (HF) vapour. Furthermore, glass substrates coated with the DPQ–MMA copolymer could be used as ‘dip sticks’ to test for trace acid in solution, turning from yellow to red upon immersion in an aqueous solution of HF. Analysis by UV–vis spectroscopic titration allowed the association constant (K a) for interaction with fluoride (as the tetrabutylammonium salt) to be calculated as 6.16 × 105 M− 1 in CH2Cl2. Polymer coatings of this type could find applications in the colorimetric detection of HF vapour, a common hazard associated with industrial processes, such as aluminium smelting.
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Halide Anion mediated dimerization of a meso unsubstituted n confused porphyrin
Chemistry-an Asian Journal, 2008Co-Authors: Jonathan L Sessler, Hiroyuki Furuta, Tatsuki Morimoto, Hideki Nanami, Takuji Ogawa, Vladimír Král, Vincent M. LynchAbstract:The new N-confused porphyrin (NCP) derivatives, meso-unsubstituted beta-alkyl-3-oxo N-confused porphyrin (3-oxo-NCP) and related macrocycles, were synthesized from appropriate pyrrolic precursors by a [3+1]-type condensation reaction. 3-Oxo-NCP forms a self-assembled dimer in dichloromethane that is stabilized by complementary hydrogen-bonding interactions arising from the peripheral amide-like moieties. The protonated form of 3-oxo-NCP was observed to bind Halide Anions (F(-), Cl(-)) through the outer NH and the inner pyrrolic NH groups, thus affording a dimer in dichloromethane. The structure of the chloride-bridged dimer in the solid state was determined by X-ray diffraction analysis.
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calix 4 pyrrole a new ion pair receptor as demonstrated by liquid liquid extraction
Journal of the American Chemical Society, 2008Co-Authors: Matthieu Wintergerst, Jonathan L Sessler, Bruce A. Moyer, Tatiana G Levitskaia, Laetitia H DelmauAbstract:Solvent-extraction studies provide confirming evidence that meso-octamethylcalix[4]pyrrole acts as an ion-pair receptor for cesium chloride and cesium bromide in nitrobenzene solution. The stoichiometry of the interaction under extraction conditions from water to nitrobenzene was determined from plots of the cesium distribution ratios vs cesium salt and receptor concentration, indicating the formation of an ion-paired 1:1:1 cesium:calix[4]pyrrole:Halide complex. The extraction results were modeled to evaluate the equilibria inherent to the solvent-extraction system, with either chloride or bromide. The binding energy between the Halide Anion and the calix[4]pyrrole was found to be about 7 kJ/mol larger for cesium chloride than for the cesium bromide. The ion-pairing free energies between the calix[4]pyrrole−Halide complex and the cesium cation are nearly the same within experimental uncertainty for either Halide, consistent with a structural model in which the Cs+ cation resides in the calix bowl. These r...
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Poly(methyl methacrylate)s with pendant calixpyrroles: polymeric extractants for Halide Anion salts
Chemical communications (Cambridge England), 2008Co-Authors: Abdullah Aydogan, Vincent M. Lynch, Ahmet Akar, Manuel Marquez, Daniel J. Coady, Christopher W. Bielawski, Jonathan L SesslerAbstract:Poly(methyl methacrylate)s containing pendant octamethylcalix[4]pyrrole subunits were prepared and demonstrated to be capable of extracting tetrabutylammonium chloride and fluoride salts from aqueous media.
Yuancheng Zhu - One of the best experts on this subject based on the ideXlab platform.
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fluorine substitution effects of Halide Anion receptors based on the combination of a distinct hydrogen bond and Anion π noncovalent interactions a theoretical investigation
RSC Advances, 2016Co-Authors: Yanzhi Liu, Kun Yuan, Zhao Yuan, Yuancheng ZhuAbstract:Noncovalent interactions between Halide Anions and a series of N-(4-vinyl-2-benzoic acid benzyl ester)-phenyl-urea containing receptors (1–8) based on hydrogen bond and (or) Anion–π interactions were investigated via theoretical calculations based on dispersion corrected density functional B3LYP-D3. Particularly, the fluorine substitution effects were deeply explored. The results showed that the substituent number and position of fluorine groups on the phenyl ring of the benzoic acid esters group has a significant effect on the configuration and cooperative properties of the hydrogen bond and Anion–π interactions. Consequently, a more feasible and rational geometric criterion for either a strong or weak Halide-Anion–π contact was proposed via three inequalities independent of any empirical parameters, which is different from the criterion proposed very recently by Albrecht and Rissanen based on their experience with solid state Anion–π interactions (Chem. Sci., 2015, 6, 354–359). Additionally, electronic properties and behavior of the systems were discussed according to the calculations on the frontier molecular orbital, total electrostatic potential and visualized weak interactions regions. It is expected that the theoretical explorations from a molecular level in this work may be useful for future experimental study and helpful for understanding the structure–activity relationship between aromatic rings and Anion–π interactions in the case of combination of distinct noncovalent interactions.
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Fluorine substitution effects of Halide Anion receptors based on the combination of a distinct hydrogen bond and Anion–π noncovalent interactions: a theoretical investigation
RSC Advances, 2016Co-Authors: Yanzhi Liu, Kun Yuan, Zhao Yuan, Yuancheng ZhuAbstract:Noncovalent interactions between Halide Anions and a series of N-(4-vinyl-2-benzoic acid benzyl ester)-phenyl-urea containing receptors (1–8) based on hydrogen bond and (or) Anion–π interactions were investigated via theoretical calculations based on dispersion corrected density functional B3LYP-D3. Particularly, the fluorine substitution effects were deeply explored. The results showed that the substituent number and position of fluorine groups on the phenyl ring of the benzoic acid esters group has a significant effect on the configuration and cooperative properties of the hydrogen bond and Anion–π interactions. Consequently, a more feasible and rational geometric criterion for either a strong or weak Halide-Anion–π contact was proposed via three inequalities independent of any empirical parameters, which is different from the criterion proposed very recently by Albrecht and Rissanen based on their experience with solid state Anion–π interactions (Chem. Sci., 2015, 6, 354–359). Additionally, electronic properties and behavior of the systems were discussed according to the calculations on the frontier molecular orbital, total electrostatic potential and visualized weak interactions regions. It is expected that the theoretical explorations from a molecular level in this work may be useful for future experimental study and helpful for understanding the structure–activity relationship between aromatic rings and Anion–π interactions in the case of combination of distinct noncovalent interactions.
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designation and exploration of Halide Anion recognition based on cooperative noncovalent interactions including hydrogen bonds and Anion π
Journal of Physical Chemistry A, 2015Co-Authors: Yanzhi Liu, Kun Yuan, Yuancheng Zhu, Zhao YuanAbstract:A novel urea-based Anion receptor with an electron-deficient aromatic structural unit, N-p-nitrophenyl-N-(4-vinyl-2-five-fluoro-benzoic acid benzyl ester)-phenyl-urea (FUR), was designed to probe the potential for Halide–Anion recognition through the cooperation of two distinct noncovalent interactions including hydrogen bonds and Anion−π in this work. The nature of the recognition interactions between Halide–Anion and the designed receptor was theoretically investigated at the molecular level. The geometric features of the hydrogen bond and Anion−π of the FUR@X– (X = F, Cl, Br, and I) systems were thoroughly investigated. The binding energies and thermodynamic information on the Halide–Anion recognitions show that the presently designed FUR might selectively recognize Anion F– based on the cooperation of the N–H···F– hydrogen bond and Anion−π interactions both in vacuum and in solvents. IR and UV–visible spectra of free FUR and FUR@F– have been simulated and discussed qualitatively, which may be helpful ...
Yanzhi Liu - One of the best experts on this subject based on the ideXlab platform.
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fluorine substitution effects of Halide Anion receptors based on the combination of a distinct hydrogen bond and Anion π noncovalent interactions a theoretical investigation
RSC Advances, 2016Co-Authors: Yanzhi Liu, Kun Yuan, Zhao Yuan, Yuancheng ZhuAbstract:Noncovalent interactions between Halide Anions and a series of N-(4-vinyl-2-benzoic acid benzyl ester)-phenyl-urea containing receptors (1–8) based on hydrogen bond and (or) Anion–π interactions were investigated via theoretical calculations based on dispersion corrected density functional B3LYP-D3. Particularly, the fluorine substitution effects were deeply explored. The results showed that the substituent number and position of fluorine groups on the phenyl ring of the benzoic acid esters group has a significant effect on the configuration and cooperative properties of the hydrogen bond and Anion–π interactions. Consequently, a more feasible and rational geometric criterion for either a strong or weak Halide-Anion–π contact was proposed via three inequalities independent of any empirical parameters, which is different from the criterion proposed very recently by Albrecht and Rissanen based on their experience with solid state Anion–π interactions (Chem. Sci., 2015, 6, 354–359). Additionally, electronic properties and behavior of the systems were discussed according to the calculations on the frontier molecular orbital, total electrostatic potential and visualized weak interactions regions. It is expected that the theoretical explorations from a molecular level in this work may be useful for future experimental study and helpful for understanding the structure–activity relationship between aromatic rings and Anion–π interactions in the case of combination of distinct noncovalent interactions.
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Fluorine substitution effects of Halide Anion receptors based on the combination of a distinct hydrogen bond and Anion–π noncovalent interactions: a theoretical investigation
RSC Advances, 2016Co-Authors: Yanzhi Liu, Kun Yuan, Zhao Yuan, Yuancheng ZhuAbstract:Noncovalent interactions between Halide Anions and a series of N-(4-vinyl-2-benzoic acid benzyl ester)-phenyl-urea containing receptors (1–8) based on hydrogen bond and (or) Anion–π interactions were investigated via theoretical calculations based on dispersion corrected density functional B3LYP-D3. Particularly, the fluorine substitution effects were deeply explored. The results showed that the substituent number and position of fluorine groups on the phenyl ring of the benzoic acid esters group has a significant effect on the configuration and cooperative properties of the hydrogen bond and Anion–π interactions. Consequently, a more feasible and rational geometric criterion for either a strong or weak Halide-Anion–π contact was proposed via three inequalities independent of any empirical parameters, which is different from the criterion proposed very recently by Albrecht and Rissanen based on their experience with solid state Anion–π interactions (Chem. Sci., 2015, 6, 354–359). Additionally, electronic properties and behavior of the systems were discussed according to the calculations on the frontier molecular orbital, total electrostatic potential and visualized weak interactions regions. It is expected that the theoretical explorations from a molecular level in this work may be useful for future experimental study and helpful for understanding the structure–activity relationship between aromatic rings and Anion–π interactions in the case of combination of distinct noncovalent interactions.
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designation and exploration of Halide Anion recognition based on cooperative noncovalent interactions including hydrogen bonds and Anion π
Journal of Physical Chemistry A, 2015Co-Authors: Yanzhi Liu, Kun Yuan, Yuancheng Zhu, Zhao YuanAbstract:A novel urea-based Anion receptor with an electron-deficient aromatic structural unit, N-p-nitrophenyl-N-(4-vinyl-2-five-fluoro-benzoic acid benzyl ester)-phenyl-urea (FUR), was designed to probe the potential for Halide–Anion recognition through the cooperation of two distinct noncovalent interactions including hydrogen bonds and Anion−π in this work. The nature of the recognition interactions between Halide–Anion and the designed receptor was theoretically investigated at the molecular level. The geometric features of the hydrogen bond and Anion−π of the FUR@X– (X = F, Cl, Br, and I) systems were thoroughly investigated. The binding energies and thermodynamic information on the Halide–Anion recognitions show that the presently designed FUR might selectively recognize Anion F– based on the cooperation of the N–H···F– hydrogen bond and Anion−π interactions both in vacuum and in solvents. IR and UV–visible spectra of free FUR and FUR@F– have been simulated and discussed qualitatively, which may be helpful ...
Vincent M. Lynch - One of the best experts on this subject based on the ideXlab platform.
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controlling structure beyond the initial coordination sphere complexation induced reversed micelle formation in calix 4 pyrrole containing diblock copolymers
Journal of the American Chemical Society, 2018Co-Authors: Xiaodong Chi, Jonathan L Sessler, Vincent M. Lynch, Gretchen Marie Peters, Chandler BrockmanAbstract:A diblock copolymer containing a strapped calix[4]pyrrole-based ion pair recognition subunit has been synthesized via RAFT polymerization. As prepared, the polymer is hydrophobic and devoid of any particular morphological form. However, upon ion pair complexation, the copolymer self-assembles to generate reverse micelles in organic media. The reverse micelles formed in this way may be used to extract alkali cation and cesium Halide Anion salts from an aqueous source into an organic receiving phase. The polymer proved more effective as an extractant than the corresponding free ion pair receptor.
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Halide Anion mediated dimerization of a meso unsubstituted n confused porphyrin
Chemistry-an Asian Journal, 2008Co-Authors: Jonathan L Sessler, Hiroyuki Furuta, Tatsuki Morimoto, Hideki Nanami, Takuji Ogawa, Vladimír Král, Vincent M. LynchAbstract:The new N-confused porphyrin (NCP) derivatives, meso-unsubstituted beta-alkyl-3-oxo N-confused porphyrin (3-oxo-NCP) and related macrocycles, were synthesized from appropriate pyrrolic precursors by a [3+1]-type condensation reaction. 3-Oxo-NCP forms a self-assembled dimer in dichloromethane that is stabilized by complementary hydrogen-bonding interactions arising from the peripheral amide-like moieties. The protonated form of 3-oxo-NCP was observed to bind Halide Anions (F(-), Cl(-)) through the outer NH and the inner pyrrolic NH groups, thus affording a dimer in dichloromethane. The structure of the chloride-bridged dimer in the solid state was determined by X-ray diffraction analysis.
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Poly(methyl methacrylate)s with pendant calixpyrroles: polymeric extractants for Halide Anion salts
Chemical communications (Cambridge England), 2008Co-Authors: Abdullah Aydogan, Vincent M. Lynch, Ahmet Akar, Manuel Marquez, Daniel J. Coady, Christopher W. Bielawski, Jonathan L SesslerAbstract:Poly(methyl methacrylate)s containing pendant octamethylcalix[4]pyrrole subunits were prepared and demonstrated to be capable of extracting tetrabutylammonium chloride and fluoride salts from aqueous media.
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Halide Anion Mediated Dimerization of a meso‐Unsubstituted N‐Confused Porphyrin
Chemistry an Asian journal, 2008Co-Authors: Hiroyuki Furuta, Jonathan L Sessler, Tatsuki Morimoto, Hideki Nanami, Takuji Ogawa, Vladimír Král, Vincent M. LynchAbstract:The new N-confused porphyrin (NCP) derivatives, meso-unsubstituted beta-alkyl-3-oxo N-confused porphyrin (3-oxo-NCP) and related macrocycles, were synthesized from appropriate pyrrolic precursors by a [3+1]-type condensation reaction. 3-Oxo-NCP forms a self-assembled dimer in dichloromethane that is stabilized by complementary hydrogen-bonding interactions arising from the peripheral amide-like moieties. The protonated form of 3-oxo-NCP was observed to bind Halide Anions (F(-), Cl(-)) through the outer NH and the inner pyrrolic NH groups, thus affording a dimer in dichloromethane. The structure of the chloride-bridged dimer in the solid state was determined by X-ray diffraction analysis.
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diprotonated sapphyrin a fluoride selective Halide Anion receptor
Journal of the American Chemical Society, 1992Co-Authors: Mitsuhiko Shionoya, Vincent M. Lynch, Hiroyuki Furuta, Anthony Harriman, Jonathan L SesslerAbstract:Prior solid-state structural evidence (Sessler, J.L.;Cyr,M.J.;Lynch,V.;McGhee, E.;J.A.J.Am.Chem. Soc. 1990, 112, 2810-2813) served to indicate that the diprotonated form of 3;8;12;13;17;22-hexaethyl-2,7,18,23-tetramethylsapphyrin ([2.2H] 2+ , as its mixed fluoride-hexafluorophosphate salt, [1.2H.F].PF 6 , is capable of encapsulating fluoride Anion within its ca. 5.5 A diameter pentaaza macrocyclic core. The present report describes solution-phase studies related to these earlier solid-state ones
