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Ion Pair

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Jonathan L Sessler - One of the best experts on this subject based on the ideXlab platform.

  • macrocycles as Ion Pair receptors
    Chemical Reviews, 2019
    Co-Authors: Qing He, Gabriela I Vargaszuniga, Jonathan L Sessler
    Abstract:

    CatIon and anIon recognitIon have both played central roles in the development of supramolecular chemistry. Much of the associated research has focused on the development of receptors for individual catIons or anIons, as well as their applicatIons in different areas. Rarely is complexatIon of the counterIons considered. In contrast, Ion Pair recognitIon chemistry, emerging from catIon and anIon coordinatIon chemistry, is a specific research field where co-complexatIon of both anIons and catIons, so-called Ion Pairs, is the center of focus. Systems used for the purpose, known as Ion Pair receptors, are typically di- or polytopic hosts that contain recognitIon sites for both catIons and anIons and which permit the concurrent binding of multiple Ions. The field of Ion Pair recognitIon has blossomed during the past decades. Several smaller reviews on the topic were published roughly 5 years ago. They provided a summary of synthetic progress and detailed the various limiting Ion recognitIon modes displayed by both acyclic and macrocyclic Ion Pair receptors known at the time. The present review is designed to provide a comprehensive and up-to-date overview of the chemistry of macrocycle-based Ion Pair receptors. We specifically focus on the relatIonship between structure and Ion Pair recognitIon, as well as applicatIons of Ion Pair receptors in sensor development, catIon and anIon extractIon, Ion transport, and logic gate constructIon.

  • molecular recognitIon under interfacial conditIons calix 4 pyrrole based cross linkable micelles for Ion Pair extractIon
    Journal of the American Chemical Society, 2017
    Co-Authors: Gretchen Marie Peters, Forrest Hammel, Chandler Brockman, Jonathan L Sessler
    Abstract:

    An anthracene-functIonalized, long-tailed calix[4]pyrrole 1, containing both an anIon-recognitIon site and catIon-recognitIon functIonality, has been synthesized and fully characterized. Upon Ion Pair complexatIon with FeF2, receptor 1 self-assembles into multimicelles in aqueous media. This aggregatIon process is ascribed to a change in polarity from nonpolar to amphiphilic induced upon concurrent anIon and catIon complexatIon and permits molecular recognitIon-based control over chemical morphology under interfacial conditIons. PhotoirradiatIon of the micelles serves to cross-link the anthracene units thus stabilizing the aggregates. The combinatIon of Ion Pair recognitIon, micelle formatIon, and cross-linking can be used to extract FeF2 Ion Pairs from bulk aqueous solutIons. The present work helps illustrate how molecular recognitIon and self-assembly may be used to control the chemistry of extractants at interfaces.

  • hemispherand strapped calix 4 pyrrole an Ion Pair receptor for the recognitIon and extractIon of lithium nitrite
    Journal of the American Chemical Society, 2016
    Co-Authors: Qing He, Vincent M Lynch, Zhan Zhang, James T Brewster, Jonathan L Sessler
    Abstract:

    The hemispherand-strapped calix[4]pyrrole (1) acts as an Ion Pair receptor that exhibits selectivity for lithium salts. In organic media (CD2Cl2 and CD3OD, v/v, 9:1), receptor 1 binds LiCl with high preference relative to NaCl, KCl, and RbCl. DFT calculatIons provided support for the observed selectivity. Single crystal structures of five different lithium Ion-Pair complexes of 1 were obtained. In the case of LiCl, a single bridging water molecule between the lithium catIon and chloride anIon was observed, while tight contact Ion Pairs were observed in the case of the LiBr, LiI, LiNO3, and LiNO2 salts. Receptor 1 proved effective as an extractant for LiNO2 under both model solid–liquid and liquid–liquid extractIon conditIons.

  • calix 4 pyrrole based Ion Pair receptors
    Accounts of Chemical Research, 2014
    Co-Authors: Jonathan L Sessler
    Abstract:

    ConspectusIon Pair receptors, which are able to bind concurrently both a catIon and an anIon, often display higher selectivity and affinity for specific Ion Pairs than simple Ion receptors capable of recognizing primarily either a catIon or an anIon. This enhancement in recognitIon functIon is attributable to direct or indirect cooperative interactIons between cobound Ions via electrostatic attractIons between oppositely charged Ions, as well as to positive allosteric effects. In additIon, by virtue of binding the counterIons of the targeted Ion, Ion Pair receptors can minimize the solvatIon of the counterIons, which can otherwise have a negative effect on the interactIons between the receptors and the targeted Ions. As a result of their more favorable interactIons, Ion Pair receptors are attractive for use in applicatIons, such as extractIon and sensing, where control of the binding interactIons is advantageous. In this Account, we illustrate this potential in the context of Ion Pair receptors based on t...

  • oligoether strapped calix 4 pyrrole an Ion Pair receptor displaying catIon dependent chloride anIon transport
    Chemistry: A European Journal, 2012
    Co-Authors: In Won Park, Jonathan L Sessler, Suman Adhikari, Yerim Yeon, Cally J E Haynes, Jennifer L Sutton, Christine C Tong, Vincent M Lynch, Philip A Gale
    Abstract:

    A ditopic Ion-Pair receptor (1), which has tunable catIon- and anIon-binding sites, has been synthesized and characterized. Spectroscopic analyses provide support for the conclusIon that receptor 1 binds fluoride and chloride anIons strongly and forms stable 1:1 complexes ([1?F]? and [1?Cl]?) with appropriately chosen salts of these anIons in acetonitrile. When the anIon complexes of 1 were treated with alkali metal Ions (Li+, Na+, K+, Cs+, as their perchlorate salts), Ion-dependent interactIons were observed that were found to depend on both the choice of added catIon and the initially complexed anIon. In the case of [1?F]?, no appreciable interactIon with the K+ Ion was seen. On the other hand, when this complex was treated with Li+ or Na+ Ions, decomplexatIon of the bound fluoride anIon was observed. In contrast to what was seen with Li+, Na+, K+, treating [1?F]? with Cs+ Ions gave rise to a stable, host-separated Ion-Pair complex, [F?1?Cs], which contains the Cs+ Ion bound in the cup-like portIon of the calix[4]pyrrole. Different complexatIon behavior was seen in the case of the chloride complex, [1?Cl]?. Here, no appreciable interactIon was observed with Na+ or K+. In contrast, treating with Li+ produces a tight Ion-Pair complex, [1?Li?Cl], in which the catIon is bound to the crown moiety. In analogy to what was seen for [1?F]?, treatment of [1?Cl]? with Cs+ Ions gives rise to a host-separated Ion-Pair complex, [Cl?1?Cs], in which the catIon is bound to the cup of the calix[4]pyrrole. As inferred from liposomal model membrane transport studies, system 1 can act as an effective carrier for several chloride anIon salts of Group?1 catIons, operating through both symport (chloride+catIon co-transport) and antiport (nitrate-for-chloride exchange) mechanisms. This transport behavior stands in contrast to what is seen for simple octamethylcalix[4]pyrrole, which acts as an effective carrier for cesium chloride but does not operates through a nitrate-for-chloride anIon exchange mechanism.

Qing He - One of the best experts on this subject based on the ideXlab platform.

  • macrocycles as Ion Pair receptors
    Chemical Reviews, 2019
    Co-Authors: Qing He, Gabriela I Vargaszuniga, Jonathan L Sessler
    Abstract:

    CatIon and anIon recognitIon have both played central roles in the development of supramolecular chemistry. Much of the associated research has focused on the development of receptors for individual catIons or anIons, as well as their applicatIons in different areas. Rarely is complexatIon of the counterIons considered. In contrast, Ion Pair recognitIon chemistry, emerging from catIon and anIon coordinatIon chemistry, is a specific research field where co-complexatIon of both anIons and catIons, so-called Ion Pairs, is the center of focus. Systems used for the purpose, known as Ion Pair receptors, are typically di- or polytopic hosts that contain recognitIon sites for both catIons and anIons and which permit the concurrent binding of multiple Ions. The field of Ion Pair recognitIon has blossomed during the past decades. Several smaller reviews on the topic were published roughly 5 years ago. They provided a summary of synthetic progress and detailed the various limiting Ion recognitIon modes displayed by both acyclic and macrocyclic Ion Pair receptors known at the time. The present review is designed to provide a comprehensive and up-to-date overview of the chemistry of macrocycle-based Ion Pair receptors. We specifically focus on the relatIonship between structure and Ion Pair recognitIon, as well as applicatIons of Ion Pair receptors in sensor development, catIon and anIon extractIon, Ion transport, and logic gate constructIon.

  • hemispherand strapped calix 4 pyrrole an Ion Pair receptor for the recognitIon and extractIon of lithium nitrite
    Journal of the American Chemical Society, 2016
    Co-Authors: Qing He, Vincent M Lynch, Zhan Zhang, James T Brewster, Jonathan L Sessler
    Abstract:

    The hemispherand-strapped calix[4]pyrrole (1) acts as an Ion Pair receptor that exhibits selectivity for lithium salts. In organic media (CD2Cl2 and CD3OD, v/v, 9:1), receptor 1 binds LiCl with high preference relative to NaCl, KCl, and RbCl. DFT calculatIons provided support for the observed selectivity. Single crystal structures of five different lithium Ion-Pair complexes of 1 were obtained. In the case of LiCl, a single bridging water molecule between the lithium catIon and chloride anIon was observed, while tight contact Ion Pairs were observed in the case of the LiBr, LiI, LiNO3, and LiNO2 salts. Receptor 1 proved effective as an extractant for LiNO2 under both model solid–liquid and liquid–liquid extractIon conditIons.

Philip A Gale - One of the best experts on this subject based on the ideXlab platform.

  • oligoether strapped calix 4 pyrrole an Ion Pair receptor displaying catIon dependent chloride anIon transport
    Chemistry: A European Journal, 2012
    Co-Authors: In Won Park, Jonathan L Sessler, Suman Adhikari, Yerim Yeon, Cally J E Haynes, Jennifer L Sutton, Christine C Tong, Vincent M Lynch, Philip A Gale
    Abstract:

    A ditopic Ion-Pair receptor (1), which has tunable catIon- and anIon-binding sites, has been synthesized and characterized. Spectroscopic analyses provide support for the conclusIon that receptor 1 binds fluoride and chloride anIons strongly and forms stable 1:1 complexes ([1?F]? and [1?Cl]?) with appropriately chosen salts of these anIons in acetonitrile. When the anIon complexes of 1 were treated with alkali metal Ions (Li+, Na+, K+, Cs+, as their perchlorate salts), Ion-dependent interactIons were observed that were found to depend on both the choice of added catIon and the initially complexed anIon. In the case of [1?F]?, no appreciable interactIon with the K+ Ion was seen. On the other hand, when this complex was treated with Li+ or Na+ Ions, decomplexatIon of the bound fluoride anIon was observed. In contrast to what was seen with Li+, Na+, K+, treating [1?F]? with Cs+ Ions gave rise to a stable, host-separated Ion-Pair complex, [F?1?Cs], which contains the Cs+ Ion bound in the cup-like portIon of the calix[4]pyrrole. Different complexatIon behavior was seen in the case of the chloride complex, [1?Cl]?. Here, no appreciable interactIon was observed with Na+ or K+. In contrast, treating with Li+ produces a tight Ion-Pair complex, [1?Li?Cl], in which the catIon is bound to the crown moiety. In analogy to what was seen for [1?F]?, treatment of [1?Cl]? with Cs+ Ions gives rise to a host-separated Ion-Pair complex, [Cl?1?Cs], in which the catIon is bound to the cup of the calix[4]pyrrole. As inferred from liposomal model membrane transport studies, system 1 can act as an effective carrier for several chloride anIon salts of Group?1 catIons, operating through both symport (chloride+catIon co-transport) and antiport (nitrate-for-chloride exchange) mechanisms. This transport behavior stands in contrast to what is seen for simple octamethylcalix[4]pyrrole, which acts as an effective carrier for cesium chloride but does not operates through a nitrate-for-chloride anIon exchange mechanism.

  • anIon and Ion Pair receptor chemistry highlights from 2000 and 2001
    Coordination Chemistry Reviews, 2003
    Co-Authors: Philip A Gale
    Abstract:

    This review article highlights advances made in abiotic anIon coordinatIon chemistry in 2000 and 2001. The structure of this review is that similar to the previous reviews in this series that covered 1997, 1998 and 1999 [P.A. Gale, Coord. Chem. Rev. 199 (2000) 18 1; P.A. Gale, Coord. Chem. Rev. 213 (2001) 79]. The review also includes examples of Ion-Pair receptors. The first sectIon examines anIon receptors that do not contain metal Ions. This is followed by a review of metal containing anIon receptors in which the metal can functIon as: (i) a coordinatIon site for the anIon; (ii) an agent withdrawing electron density from the receptor; (iii) an organisatIonal element in the receptor; (iv) a sensor; and (v) a co-bound guest in Ion-Pair receptor. Examples of the role of anIons in directing the self-assembly of complex molecular architectures are presented in the final sectIon.

Vincent M Lynch - One of the best experts on this subject based on the ideXlab platform.

  • hemispherand strapped calix 4 pyrrole an Ion Pair receptor for the recognitIon and extractIon of lithium nitrite
    Journal of the American Chemical Society, 2016
    Co-Authors: Qing He, Vincent M Lynch, Zhan Zhang, James T Brewster, Jonathan L Sessler
    Abstract:

    The hemispherand-strapped calix[4]pyrrole (1) acts as an Ion Pair receptor that exhibits selectivity for lithium salts. In organic media (CD2Cl2 and CD3OD, v/v, 9:1), receptor 1 binds LiCl with high preference relative to NaCl, KCl, and RbCl. DFT calculatIons provided support for the observed selectivity. Single crystal structures of five different lithium Ion-Pair complexes of 1 were obtained. In the case of LiCl, a single bridging water molecule between the lithium catIon and chloride anIon was observed, while tight contact Ion Pairs were observed in the case of the LiBr, LiI, LiNO3, and LiNO2 salts. Receptor 1 proved effective as an extractant for LiNO2 under both model solid–liquid and liquid–liquid extractIon conditIons.

  • oligoether strapped calix 4 pyrrole an Ion Pair receptor displaying catIon dependent chloride anIon transport
    Chemistry: A European Journal, 2012
    Co-Authors: In Won Park, Jonathan L Sessler, Suman Adhikari, Yerim Yeon, Cally J E Haynes, Jennifer L Sutton, Christine C Tong, Vincent M Lynch, Philip A Gale
    Abstract:

    A ditopic Ion-Pair receptor (1), which has tunable catIon- and anIon-binding sites, has been synthesized and characterized. Spectroscopic analyses provide support for the conclusIon that receptor 1 binds fluoride and chloride anIons strongly and forms stable 1:1 complexes ([1?F]? and [1?Cl]?) with appropriately chosen salts of these anIons in acetonitrile. When the anIon complexes of 1 were treated with alkali metal Ions (Li+, Na+, K+, Cs+, as their perchlorate salts), Ion-dependent interactIons were observed that were found to depend on both the choice of added catIon and the initially complexed anIon. In the case of [1?F]?, no appreciable interactIon with the K+ Ion was seen. On the other hand, when this complex was treated with Li+ or Na+ Ions, decomplexatIon of the bound fluoride anIon was observed. In contrast to what was seen with Li+, Na+, K+, treating [1?F]? with Cs+ Ions gave rise to a stable, host-separated Ion-Pair complex, [F?1?Cs], which contains the Cs+ Ion bound in the cup-like portIon of the calix[4]pyrrole. Different complexatIon behavior was seen in the case of the chloride complex, [1?Cl]?. Here, no appreciable interactIon was observed with Na+ or K+. In contrast, treating with Li+ produces a tight Ion-Pair complex, [1?Li?Cl], in which the catIon is bound to the crown moiety. In analogy to what was seen for [1?F]?, treatment of [1?Cl]? with Cs+ Ions gives rise to a host-separated Ion-Pair complex, [Cl?1?Cs], in which the catIon is bound to the cup of the calix[4]pyrrole. As inferred from liposomal model membrane transport studies, system 1 can act as an effective carrier for several chloride anIon salts of Group?1 catIons, operating through both symport (chloride+catIon co-transport) and antiport (nitrate-for-chloride exchange) mechanisms. This transport behavior stands in contrast to what is seen for simple octamethylcalix[4]pyrrole, which acts as an effective carrier for cesium chloride but does not operates through a nitrate-for-chloride anIon exchange mechanism.

Robin K. Dutta - One of the best experts on this subject based on the ideXlab platform.

  • Premicellar and micelle formatIon behavior of dye surfactant Ion Pairs in aqueous solutIons: deprotonatIon of dye in Ion Pair micelles.
    Journal of Colloid and Interface Science, 2008
    Co-Authors: Biren Gohain, Robin K. Dutta
    Abstract:

    Abstract The premicellar and micelle formatIon behavior of dye surfactant Ion Pairs in aqueous solutIons monitored by surface tensIon and spectroscopic measurements has been described. The measurements have been made for three anIonic sulfonephthalein dyes and catIonic surfactants of different chain lengths, head groups, and counterIons. The observatIons have been attributed to the formatIon of closely packed dye surfactant Ion Pairs which is similar to nonIonic surfactants in very dilute concentratIons of the surfactant. These Ion Pairs dominate in the monolayer at the air–water interface of the aqueous dye surfactant solutIons below the CMC of the pure surfactant. It has been shown that the dye in the Ion Pair deprotonates on micelle formatIon by the Ion Pair surfactants at near CMC but submicellar surfactant concentratIons. The results of an equilibrium study at varying pH agree with the model of deprotonated 1:1 dye–surfactant Ion Pair formatIon in the near CMC submicellar solutIons. At concentratIons above the CMC of the catIonic surfactant the dye is solubilized in normal micelles and the monolayer at the air–water interface consists of the catIonic surfactant alone even in the presence of the dyes.

  • Protonated dye-surfactant Ion Pair formatIon between neutral red and anIonic surfactants in aqueous submicellar solutIons
    Journal of Molecular Liquids, 2008
    Co-Authors: Biren Gohain, Surashree Sarma, Robin K. Dutta
    Abstract:

    Spectral and surface tensIon behavior of aqueous neutral red in the presence of sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl sulfonate (SDSN) have been studied to understand the nature of the interactIons in their submicellar concentratIon ranges. The variatIons in spectra and surface tensIon with variatIon in the concentratIons of the surfactants suggest the formatIon of a 1:1 close-packed dye-surfactant Ion Pair, HNR+{radical dot}S- between the acid form, HNR+ of the dye and the surfactant anIon at very low concentratIons of the surfactant below critical micelle concentratIon (cmc) of the pure surfactant. The dye-surfactant Ion Pair behaves like a nonIonic surfactant having higher efficiency and lower cmc than that of the corresponding pure anIonic surfactant. The Ion Pairs are adsorbed on the air/water interface at very low concentratIons of the surfactant. As the concentratIon of the surfactant increases and the Ion Pairs form micelles of their own, the dye in the Ion Pair is protonated to form H2NR2+{radical dot}S-. As the cmc of the pure surfactant is approached, the protonatIon equilibrium gradually reverses and pure surfactant Ions gradually replace the Ion Pairs at the interface. Finally, a homogeneous monolayer of pure surfactant anIons exists at the air/water interface and the dye remain solubilized in pure micelles above the cmc of the pure surfactant. The equilibrium constants, Kc for the close-packed protonated dye-surfactant Ion Pair (PDSIP) formatIon have been determined at varying pH. The submicellar interactIon has been found to be stronger with SDS than SDBS. The plots of logarithm of Kc vs. pH have been found to be quite linear which consolidates the assumptIon of formatIon of the species, H2NR2+{radical dot}S-. The interactIon is driven by enthalpy as well as entropy. © 2008 Elsevier B.V. All rights reserved.