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Solvent-driven aqueous separations for hypersaline brine concentration and resource recovery. TRENDS IN CHEMISTRY 2022. [DOI: 10.1016/j.trechm.2022.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Forero-Martinez NC, Cortes-Huerto R, Benedetto A, Ballone P. Thermoresponsive Ionic Liquid/Water Mixtures: From Nanostructuring to Phase Separation. Molecules 2022; 27:1647. [PMID: 35268747 PMCID: PMC8912101 DOI: 10.3390/molecules27051647] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/15/2022] [Accepted: 02/28/2022] [Indexed: 12/10/2022] Open
Abstract
The thermodynamics, structures, and applications of thermoresponsive systems, consisting primarily of water solutions of organic salts, are reviewed. The focus is on organic salts of low melting temperatures, belonging to the ionic liquid (IL) family. The thermo-responsiveness is represented by a temperature driven transition between a homogeneous liquid state and a biphasic state, comprising an IL-rich phase and a solvent-rich phase, divided by a relatively sharp interface. Demixing occurs either with decreasing temperatures, developing from an upper critical solution temperature (UCST), or, less often, with increasing temperatures, arising from a lower critical solution temperature (LCST). In the former case, the enthalpy and entropy of mixing are both positive, and enthalpy prevails at low T. In the latter case, the enthalpy and entropy of mixing are both negative, and entropy drives the demixing with increasing T. Experiments and computer simulations highlight the contiguity of these phase separations with the nanoscale inhomogeneity (nanostructuring), displayed by several ILs and IL solutions. Current applications in extraction, separation, and catalysis are briefly reviewed. Moreover, future applications in forward osmosis desalination, low-enthalpy thermal storage, and water harvesting from the atmosphere are discussed in more detail.
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Affiliation(s)
- Nancy C. Forero-Martinez
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 9, 55128 Mainz, Germany;
- Max-Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | | | - Antonio Benedetto
- School of Physics, University College Dublin, 94568 Dublin, Ireland; (A.B.); (P.B.)
- Conway Institute for Biomolecular and Biomedical Research, University College Dublin, 94568 Dublin, Ireland
- Department of Sciences, University of Roma Tre, 00146 Rome, Italy
| | - Pietro Ballone
- School of Physics, University College Dublin, 94568 Dublin, Ireland; (A.B.); (P.B.)
- Conway Institute for Biomolecular and Biomedical Research, University College Dublin, 94568 Dublin, Ireland
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3
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Abstract
A halogen-bonded complex containing a pair of anions can be made more stable than the isolated anions if the Lewis acid is a long carbon chain, fully substituted by CN groups, with an I atom on one end and a COO− group on the other, with Cl− as base.
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Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, USA
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4
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Fan D, Chen L, Wang C, Yin S, Mo Y. Inter-anion chalcogen bonds: Are they anti-electrostatic in nature? J Chem Phys 2021; 155:234302. [PMID: 34937369 DOI: 10.1063/5.0076872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Inter-anion hydrogen and halogen bonds have emerged as counterintuitive linkers and inspired us to expand the range of this unconventional bonding pattern. Here, the inter-anion chalcogen bond (IAChB) was proposed and theoretically analyzed in a series of complexes formed by negatively charged bidentate chalcogen bond donors with chloride anions. The kinetic stability of IAChB was evidenced by the minima on binding energy profiles and further supported by ab initio molecular dynamic simulations. The block-localized wave function (BLW) method and its subsequent energy decomposition (BLW-ED) approach were employed to elucidate the physical origin of IAChB. While all other energy components vary monotonically as anions get together, the electrostatic interaction behaves exceptionally as it experiences a Coulombic repulsion barrier. Before reaching the barrier, the electrostatic repulsion increases with the shortening Ch⋯Cl- distance as expected from classical electrostatics. However, after passing the barrier, the electrostatic repulsion decreases with the Ch⋯Cl- distance shortening and subsequently turns into the most favorable trend among all energy terms at short ranges, representing a dominating force for the kinetic stability of inter-anions. For comparison, all energy components exhibit the same trends and vary monotonically in the conventional counterparts where donors are neutral. By comparing inter-anions and their conventional counterparts, we found that only the electrostatic energy term is affected by the extra negative charge. Remarkably, the distinctive (nonmonotonic) electrostatic energy profiles were reproduced using quantum mechanical-based atomic multipoles, suggesting that the crucial electrostatic interaction in IAChB can be rationalized within the classical electrostatic theory just like conventional non-covalent interactions.
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Affiliation(s)
- Dan Fan
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Li Chen
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Changwei Wang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Shiwei Yin
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Yirong Mo
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, North Carolina 27401, USA
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5
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Chen L, Feng Q, Wang C, Yin S, Mo Y. Classical Electrostatics Remains the Driving Force for Interanion Hydrogen and Halogen Bonding. J Phys Chem A 2021; 125:10428-10438. [PMID: 34818021 DOI: 10.1021/acs.jpca.1c09250] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interanion hydrogen bonding (IAHB) and halogen bonding (IAXB) have emerged as a counterintuitive linker in a range of fascinating applications. Despite the overall repulsive (positive) binding energy, anions are trapped in a local minimum with its corresponding transition state (TS) preventing dissociation. In other words, the adduct of anions is metastable. Seemingly, the electrostatic paradigm and force field description of hydrogen/halogen bonding (HB/XB) are challenged, because of the preconceived Coulombic repulsion. Aiming at an insightful understanding of these interanion phenomena, we employed the energy decomposition approach based on the block-localized wavefunction method (BLW-ED) to investigate a series of exemplary interanion complexes. As expected, the key distinction from the conventional HB/XB lies in the electrostatic interaction, which is not increasingly repulsive as anions gradually approach to each other. Rather, there is a Coulombic barrier at a certain point. After this point, the electrostatic repulsion diminishes with the decreasing distance between anions. Differently, other energy components vary monotonically just like in conventional cases. The nonmonotonic characteristic of the electrostatic interaction in interanion complexes was reproduced using the multipole expansion in AMOEBA polarizable force field in which the state-specified atomic multipoles were adopted. This suggests that the nonmonotonicity can be well interpreted by classical electrostatic theory and there is no conceptual difference between conventional HB/XB and IAHB/IAXB. The stability of IAHB/IAXB depends on the competition between the local attractive HB/XB and the global Coulombic repulsion of net charges, though there is cooperativity between these two contrasting forces. This concise model was supported by the attractive IAHB/IAXB in modified molecular capsules, which exhibit strong quadruple HB/XBs and a considerable distance between charged substituents.
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Affiliation(s)
- Li Chen
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Qiuyan Feng
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Changwei Wang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Shiwei Yin
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Yirong Mo
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, North Carolina 27401, United States
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7
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MacDonald TC, Feringa BL, Price WS, Wezenberg SJ, Beves JE. Controlled Diffusion of Photoswitchable Receptors by Binding Anti-electrostatic Hydrogen-Bonded Phosphate Oligomers. J Am Chem Soc 2020; 142:20014-20020. [PMID: 33180496 PMCID: PMC7735709 DOI: 10.1021/jacs.0c09072] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Indexed: 12/12/2022]
Abstract
Dihydrogen phosphate anions are found to spontaneously associate into anti-electrostatic oligomers via hydrogen bonding interactions at millimolar concentrations in DMSO. Diffusion NMR measurements supported formation of these oligomers, which can be bound by photoswitchable anion receptors to form large bridged assemblies of approximately three times the volume of the unbound receptor. Photoisomerization of the oligomer-bound receptor causes a decrease in diffusion coefficient of up to 16%, corresponding to a 70% increase in effective volume. This new approach to external control of diffusion opens prospects in controlling molecular transport using light.
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Affiliation(s)
| | - Ben L. Feringa
- Stratingh Institute for Chemistry, University
of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - William S. Price
- School of Science, Western Sydney University, Penrith, NSW 2751, Australia
| | - Sander J. Wezenberg
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Jonathon E. Beves
- School of Chemistry, University of New South Wales Sydney, NSW 2052, Australia
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8
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McNally JS, Foo ZH, Deshmukh A, Orme CJ, Lienhard JH, Wilson AD. Solute displacement in the aqueous phase of water-NaCl-organic ternary mixtures relevant to solvent-driven water treatment. RSC Adv 2020; 10:29516-29527. [PMID: 35521115 PMCID: PMC9055965 DOI: 10.1039/d0ra06361d] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 07/29/2020] [Indexed: 11/21/2022] Open
Abstract
Twelve water miscible organic solvents (MOS): acetone, tetrahydrofuran, isopropanol, acetonitrile, dimethyl sulfoxide, 1,4-dioxane, dimethylacetamide, N-methyl-2-pyrrolidone, trifluoroethanol, isopropylamine, dimethylformamide, and dimethyl ether (DME) were used to produce ternary mixtures of water-NaCl-MOS relevant to MOS-driven fractional precipitation. The aqueous-phase composition of the ternary mixture at liquid-liquid equilibrium and liquid-solid endpoint was established through quantitative nuclear magnetic resonance and mass balance. The results highlight the importance of considering the hydrated concentrations of salts and suggest that at high salt concentrations and low MOS concentration, the salt concentration is governed by competition between the salt ions and MOS molecules. Under these conditions a LS phase boundary is established, over which one mole of salt is replaced by one mole of MOS (solute displacement). At higher MOS concentrations, MOS with higher water affinity deviate from the one-to-one solute exchange but maintain a LS boundary with a homogenous liquid phase, while MOS with lower water affinity form a liquid-liquid phase boundary. DME is found to function effectively as an MOS for fractional precipitation, precipitating 97.7% of the CaSO4 from a saturated solution, a challenging scalant. DME-driven water softening recycles the DME within the system improving the atom-efficiency over existing seawater desalination pretreatments by avoiding chemical consumption.
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Affiliation(s)
- Joshua S McNally
- Idaho National Laboratory P.O. Box 1625 MS 2208 Idaho Falls ID 83415-2208 USA
| | - Zi Hao Foo
- Rohsenow Kendall Heat Transfer Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge MA 02139-4307 USA
| | - Akshay Deshmukh
- Rohsenow Kendall Heat Transfer Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge MA 02139-4307 USA
| | - Christopher J Orme
- Idaho National Laboratory P.O. Box 1625 MS 2208 Idaho Falls ID 83415-2208 USA
| | - John H Lienhard
- Rohsenow Kendall Heat Transfer Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge MA 02139-4307 USA
| | - Aaron D Wilson
- Idaho National Laboratory P.O. Box 1625 MS 2208 Idaho Falls ID 83415-2208 USA
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Zhao W, Flood AH, White NG. Recognition and applications of anion-anion dimers based on anti-electrostatic hydrogen bonds (AEHBs). Chem Soc Rev 2020; 49:7893-7906. [PMID: 32677649 DOI: 10.1039/d0cs00486c] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Based on Coulomb's Law alone, electrostatic repulsion between two anions is expected to prevent their dimerization. Contrary to that idea, this Tutorial Review will present evidence showing that anion-anion dimers of protic hydroxyanions can form readily, and describe conditions that facilitate their formation. From X-ray crystal structures, we learn that hydroxyanions dimerize and oligomerize by overcoming long-range electrostatic opposition. Common examples are hydroxyanions of phosphate, sulfate, and carbonate, often in partnership with charged and neutral receptors. Short-range hydrogen bonds between anionic donors and acceptors are defined as anti-electrostatic hydrogen bonds (AEHBs) with insight from theoretical studies. While anion dimers are difficult to identify unequivocally in solution, these solution dimers have recently been definitively identified. The development of the supramolecular chemistry of anion-anion dimers has led to applications in hierarchical assemblies, such as supramolecular polymers and hydrogen bonded organic frameworks.
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Affiliation(s)
- Wei Zhao
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN 47405, USA.
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Kang H, Suich DE, Davies JF, Wilson AD, Urban JJ, Kostecki R. Molecular insight into the lower critical solution temperature transition of aqueous alkyl phosphonium benzene sulfonates. Commun Chem 2019. [DOI: 10.1038/s42004-019-0151-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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11
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Williams NJ, Seipp CA, Brethomé FM, Ma YZ, Ivanov AS, Bryantsev VS, Kidder MK, Martin HJ, Holguin E, Garrabrant KA, Custelcean R. CO2 Capture via Crystalline Hydrogen-Bonded Bicarbonate Dimers. Chem 2019. [DOI: 10.1016/j.chempr.2018.12.025] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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12
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White NG. Antielectrostatically hydrogen bonded anion dimers: counter-intuitive, common and consistent. CrystEngComm 2019. [DOI: 10.1039/c9ce01118h] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A Cambridge Structural Database survey reveals that antielectrostatically hydrogen bonded dimers occur frequently between a wide range of anions.
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Affiliation(s)
- Nicholas G. White
- Research School of Chemistry
- The Australian National University
- Canberra
- Australia
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Cullen DA, Gardiner MG, White NG. A three dimensional hydrogen bonded organic framework assembled through antielectrostatic hydrogen bonds. Chem Commun (Camb) 2019; 55:12020-12023. [DOI: 10.1039/c9cc06707h] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A 3D hydrogen bonded organic framework was assembled in water from tetraamidinium cations and antielectrostatically hydrogen bonded bicarbonate dimers.
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Affiliation(s)
- Duncan A. Cullen
- Research School of Chemistry
- The Australian National University
- Canberra
- Australia
| | - Michael G. Gardiner
- Research School of Chemistry
- The Australian National University
- Canberra
- Australia
| | - Nicholas G. White
- Research School of Chemistry
- The Australian National University
- Canberra
- Australia
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14
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Niemann T, Zaitsau D, Strate A, Villinger A, Ludwig R. Cationic clustering influences the phase behaviour of ionic liquids. Sci Rep 2018; 8:14753. [PMID: 30283059 PMCID: PMC6170405 DOI: 10.1038/s41598-018-33176-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/19/2018] [Indexed: 11/17/2022] Open
Abstract
“Unlike charges attract, but like charges repel”. This conventional wisdom has been recently challenged for ionic liquids. It could be shown that like-charged ions attract each other despite the powerful opposing electrostatic forces. In principle, cooperative hydrogen bonding between ions of like-charge can overcome the repulsive Coulomb interaction while pushing the limits of chemical bonding. The key challenge of this solvation phenomenon is to establish design principles for the efficient formation of clusters of like-charged ions in ionic liquids. This is realised here for a set of well-suited ionic liquids including the same hydrophobic anion but different cations all equipped with hydroxyethyl groups for possible H-bonding. The formation of H-bonded cationic clusters can be controlled by the delocalization of the positive charge on the cations. Strongly localized charge results in cation-anion interaction, delocalized charge leads to the formation of cationic clusters. For the first time we can show, that the cationic clusters influence the properties of ILs. ILs comprising these clusters can be supercooled and form glasses. Crystalline structures are obtained only, if the ILs are dominantly characterized by the attraction between opposite-charged ions resulting in conventional ion pairs. That may open a new path for controlling glass formation and crystallization. The glass temperatures and the phase transitions of the ILs are observed by differential scanning calorimetry (DSC) and infrared (IR) spectroscopy.
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Affiliation(s)
- Thomas Niemann
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Dr. -Lorenz-Weg 2, 18059, Rostock, Germany
| | - Dimitri Zaitsau
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Dr. -Lorenz-Weg 2, 18059, Rostock, Germany
| | - Anne Strate
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Dr. -Lorenz-Weg 2, 18059, Rostock, Germany
| | - Alexander Villinger
- Universität Rostock, Institut für Chemie, Abteilung für Anorganische Chemie, Albert-Einstein-Str. 3a, 18059, Rostock, Germany
| | - Ralf Ludwig
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Dr. -Lorenz-Weg 2, 18059, Rostock, Germany. .,Department Life, Light & Matter, University of Rostock, 18051, Rostock, Germany. .,Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Str. 29a, 18059, Rostock, Germany.
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Dobscha JR, Debnath S, Fadler RE, Fatila EM, Pink M, Raghavachari K, Flood AH. Host–Host Interactions Control Self‐assembly and Switching of Triple and Double Decker Stacks of Tricarbazole Macrocycles Co‐assembled with anti‐Electrostatic Bisulfate Dimers. Chemistry 2018; 24:9841-9852. [DOI: 10.1002/chem.201800827] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Indexed: 12/20/2022]
Affiliation(s)
- James R. Dobscha
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
| | - Sibali Debnath
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
| | - Rachel E. Fadler
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
| | - Elisabeth M. Fatila
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
- Current address: Department of Chemistry Louisiana Tech University 1 Adams Boulevard Ruston LA 71272 USA
| | - Maren Pink
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
| | - Krishnan Raghavachari
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
| | - Amar H. Flood
- Department of Chemistry Indiana University 800 E. Kirkwood Avenue Bloomington IN 47405 USA
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Fatila EM, Pink M, Twum EB, Karty JA, Flood AH. Phosphate-phosphate oligomerization drives higher order co-assemblies with stacks of cyanostar macrocycles. Chem Sci 2018; 9:2863-2872. [PMID: 29780454 PMCID: PMC5941797 DOI: 10.1039/c7sc05290a] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/09/2018] [Indexed: 01/31/2023] Open
Abstract
The importance of phosphate in biology and chemistry has long motivated investigation of its recognition. Despite this interest, phosphate's facile oligomerization is only now being examined following the discovery of complexes of anion-anion dimers of hydroxyanions. Here we address how oligomerization dictates phosphate's recognition properties when engaged with planar cyanostar macrocycles that can also oligomerize by stacking. The crystal structure of cyanostar with phosphate shows an unprecedented tetrameric stack of cyanostar macrocycles threaded by a phosphate trimer, [H2PO4···H2PO4···H2PO4]3-. The solution behaviour, studied as a function of solvent quality, highlights how dimers and trimers of phosphate drive formation of higher order stacks of cyanostar into dimer, trimer and tetramer co-assemblies. Solution behaviors differ significantly from simpler complexes of bisulfate hydroxyanion dimers. Phosphate oligomerization is: (1) preferred over ion pairing with tetrabutylammonium cations, (2) inhibits disassembly of the complexes upon dilution, and (3) resists interference from competitive anion solvation. The phosphate oligomers also appear critical for stability; complexation of just one phosphate with cyanostars is unfavored. The cyanostar's ability to self-assemble is found to create a tubular, highly electropositive cavity that complements the size and shape of the phosphate oligomers as well as their higher charge. When given the opportunity, phosphate will cooperate with the receptor to form co-assembled architectures.
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Affiliation(s)
- Elisabeth M Fatila
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA .
| | - Maren Pink
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA .
| | - Eric B Twum
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA .
| | - Jonathan A Karty
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA .
| | - Amar H Flood
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA .
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Weinhold F. Theoretical Prediction of Robust Second-Row Oxyanion Clusters in the Metastable Domain of Antielectrostatic Hydrogen Bonding. Inorg Chem 2018; 57:2035-2044. [PMID: 29381336 DOI: 10.1021/acs.inorgchem.7b02943] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We provide ab initio and density functional theory evidence for a family of surprisingly robust like-charged clusters of common HSO4- and H2PO4- oxyanions, ranging up to tetramers of net charge 4-. Our results support other recent theoretical and experimental evidence for "antielectrostatic" hydrogen-bonded (AEHB) species that challenge conventional electrostatic conceptions and force-field modeling of closed-shell ion interactions. We provide structural and energetic descriptors of the predicted kinetic well-depths (in the range 3-10 kcal/mol) and barrier widths (in the range 2-4 Å) for simple AEHB dimers, including evidence of extremely strong hydrogen bonding in the fluoride-bisulfate dianion. For more complex polyanionic species, we employ natural-bond-orbital-based descriptors to characterize the electronic features of the cooperative hydrogen-bonding network that are able to successfully defy Coulomb explosion. The computational results suggest a variety of kinetically stable AEHB species that may be suitable for experimental detection as long-lived gas-phase species or structural units of condensed phases, despite the imposing electrostatic barriers that oppose their formation under ambient conditions.
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Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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