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Otomo T, Suzuki H, Iida R, Takayanagi T. SN1 reaction mechanisms of tert-butyl chloride in aqueous solution: What can be learned from reaction path search calculations and trajectory calculations for small hydrated clusters? COMPUT THEOR CHEM 2021. [DOI: 10.1016/j.comptc.2021.113278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Darvas M, Jorge M, Cordeiro MNDS, Kantorovich SS, Sega M, Jedlovszky P. Calculation of the intrinsic solvation free energy profile of an ionic penetrant across a liquid-liquid interface with computer simulations. J Phys Chem B 2013; 117:16148-56. [PMID: 24175995 PMCID: PMC3871283 DOI: 10.1021/jp404699t] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 10/10/2013] [Indexed: 11/29/2022]
Abstract
We introduce the novel concept of an intrinsic free energy profile, allowing one to remove the artificial smearing caused by thermal capillary waves, which renders difficulties for the calculation of free energy profiles across fluid interfaces in computer simulations. We apply this concept to the problem of a chloride ion crossing the interface between water and 1,2-dichloroethane and show that the present approach is able to reveal several important features of the free energy profile which are not detected with the usual, nonintrinsic calculations. Thus, in contrast to the nonintrinsic profile, a free energy barrier is found at the aqueous side of the (intrinsic) interface, which is attributed to the formation of a water "finger" the ion pulls with itself upon approaching the organic phase. Further, by the presence of a nonsampled region, the intrinsic free energy profile clearly indicates the coextraction of the first hydration shell water molecules of the ion when entering the organic phase.
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Affiliation(s)
- Mária Darvas
- Sector
of Molecular and Statistical Biophysics, SISSA, 265 via Bonomea, I-34136 Trieste, Italy
| | - Miguel Jorge
- Department
of Chemical and Process Engineering, University
of Strathclyde, 75 Montrose
Street, Glasgow G1 1XJ, United Kingdom
| | - M. Natalia D. S. Cordeiro
- Faculdade
de Ciências da Universidade do Porto, REQUIMTE, Rua do Campo
Alegre, 687, 4169-007 Porto, Portugal
| | - Sofia S. Kantorovich
- Faculty
of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
- Institute
of Mathematics and Computer Sciences, Ural
Federal University, 51
Lenin Avenue, R-620083 Ekaterinburg, Russia
- Department
of Physics, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Marcello Sega
- Department
of Physics, University of Rome “Tor
Vergata”, via
della Ricerca Scientifica 1, I-00133 Rome, Italy
- Institut
für Computergestützte Biologische Chemie, University of Vienna, Währinger Strasse 17, A-1090 Vienna, Austria
| | - Pál Jedlovszky
- Laboratory
of Interfaces and Nanosize Systems, Institute of Chemistry, Eötvös Loránd University, Pázmány P. Stny 1/A, H-1117 Budapest, Hungary
- MTA-BME
Research Group of Technical Analytical Chemistry, Szt. Gellért tér 4, H-1111 Budapest, Hungary
- Department
of Chemistry, EKF, Leányka utca 6, H-3300 Eger, Hungary
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Wick CD, Dang LX. Computational investigation of the influence of organic-aqueous interfaces on NaCl dissociation dynamics. J Chem Phys 2010; 132:044702. [DOI: 10.1063/1.3299279] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Shim Y, Kim HJ. MD Study of SN1 Reactivity of 2-Chloro-2-methylpropane in the Room-Temperature Ionic Liquid 1-Ethyl-3-methylimidazolium Hexafluorophosphate. J Phys Chem B 2008; 112:2637-43. [DOI: 10.1021/jp710128p] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Youngseon Shim
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and Department of Physics, Korea University, Seoul 136-701, Korea
| | - Hyung J. Kim
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and Department of Physics, Korea University, Seoul 136-701, Korea
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Winter N, Benjamin I. Molecular Dynamics Study of a Model SN1 Dissociation Reaction at Liquid/Liquid Interfaces: Effect of Liquid Polarity. Isr J Chem 2007. [DOI: 10.1560/ijc.47.1.115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Peters KS. Nature of Dynamic Processes Associated with the SN1 Reaction Mechanism. Chem Rev 2007; 107:859-73. [PMID: 17319730 DOI: 10.1021/cr068021k] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Kevin S Peters
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, Colorado 80309-0215, USA
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Sieffert N, Wipff G. Importance of Interfacial Adsorption in the Biphasic Hydroformylation of Higher Olefins Promoted by Cyclodextrins: A Molecular Dynamics Study at the Decene/Water Interface. Chemistry 2007; 13:1978-90. [PMID: 17143921 DOI: 10.1002/chem.200601150] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We report herein a molecular dynamics study of the main species involved in the hydroformylation of higher olefins promoted by cyclodextrins in 1-decene/water biphasic systems at a temperature of 350 K. The two liquids form a well-defined sharp interface of approximately 7 A width in the absence of solute; the decene molecules are generally oriented "parallel" to the interface where they display transient contacts with water. We first focused on rhodium complexes bearing water-soluble TPPTS(3-) ligands (where TPPTS(3-) represents tris(m-sulfonatophenyl)phosphine) involved in the early steps of the reaction. The most important finding concerned the surface activity of the "active" form of the catalyst [RhH(CO)(TPPTS)(2)](6-), the [RhH(CO)(2)(TPPTS)(2)](6-) complex, and the key reaction intermediate [RhH(CO)(TPPTS)(2)(decene)](6-) (with the olefin pi-coordinated to the metal center) which are adsorbed at the water side of the interface in spite of their -6 charge. The free TPPTS(3-) ligands themselves are also surface-active, whereas the -9 charged catalyst precursor [RhH(CO)(TPPTS)(3)](9-) prefers to be solubilized in water. The role of cyclodextrins was then investigated by performing simulations on 2,6-dimethyl-beta-cyclodextrin ("CD") and its inclusion complexes with the reactant (1-decene), a reaction product (undecanal), and the corresponding key reaction intermediate [RhH(CO)(TPPTS)(2)(decene)](6-) as guests; they were all shown to be surface-active and prefer the interface over the bulk aqueous phase. These results suggest that the biphasic hydroformylation of higher olefins takes place "right" at the interface and that the CDs promote the "meeting" of the olefin and the catalyst in this peculiar region of the solution by forming inclusion complexes "preorganized" for the reaction. Our results thus point to the importance of adsorption at the liquid/liquid interface in this important phase-transfer-catalyzed reaction.
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Affiliation(s)
- Nicolas Sieffert
- Laboratoire MSM, UMR CNRS 7177, Institut de Chimie, 4 rue B. Pascal, 67 000 Strasbourg, France.
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Benjamin I. Theoretical Studies of Solute Vibrational Energy Relaxation at Liquid Interfaces. J Phys Chem B 2006; 110:9375-82. [PMID: 16686479 DOI: 10.1021/jp056420y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent advances in the theoretical understanding of solute vibrational energy relaxation at liquid interfaces and surfaces are described. Non-equilibrium molecular dynamics simulations of the relaxation of an initially excited solute molecule are combined with equilibrium force autocorrelation calculations to gain insight into the factors that influence the vibrational relaxation rate. Diatomic and triatomic nonpolar, polar, and ionic solute molecules adsorbed at the liquid/vapor interface of several liquids as well as at the water/CCl(4) liquid/liquid interface are considered. In general, the vibrational relaxation rate is significantly slower (a factor of 3 to 4) at the liquid/vapor and liquid/liquid interface than in the bulk due to the reduced density, which gives rise to a reduced contribution of the repulsive solvent-solute forces on the vibrational mode. The surface effects on the ionic solutes are much smaller (50% or less slower relaxation relative to the bulk). This is due to the fact that ionic solutes at the interface are able to keep part of their solvation shell to a degree that depends on their size. Thus, a significant portion of the repulsive forces is maintained. A high degree of correlation is found between the peak height of the solvent-solute radial distribution function and the vibrational relaxation rate. The relaxation rate at the liquid/liquid interface strongly depends on the location of the solute across the interface and correlates with the change in the density and polarity profile of the interface.
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Affiliation(s)
- Ilan Benjamin
- Department of Chemistry and Biochemistry, University of California at Santa Cruz, Santa Cruz, CA 95064, USA
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Sieffert N, Wipff G. Adsorption at the Liquid−Liquid Interface in the Biphasic Rhodium Catalyzed Hydroformylation of Olefins Promoted by Cyclodextrins: A Molecular Dynamics Study. J Phys Chem B 2006; 110:4125-34. [PMID: 16509706 DOI: 10.1021/jp057023q] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using molecular dynamics (MD) simulations, we investigate the interfacial distribution of partners involved in the phase transfer rhodium catalyzed hydroformylation of olefins promoted by beta-cyclodextrins (beta-CDs). The beta-CDs, the reactant (alkene), product (aldehyde), several rhodium complexes (the catalyst, its precursor, and its alkene adduct) are simulated at the water-"oil" interface, where oil is represented by chloroform or hexane. It is shown that unsubstituted beta-CD and its 6-methylated and 2,6-dimethylated analogues adsorb at the interface, whereas the liposoluble permethylated CD does not. The precursor of the catalyst [RhH(CO)(TPPTS)3]9- (with triphenylphosphine trisulfonated TPPTS3- ligands) sits in water, but the less charged [RhH(CO)(TPPTS)2]6- catalyst and the [RhH(CO)(TPPTS)2(alkene)]6- reaction intermediate are clearly surface active. The TPPTS3- anions also concentrate at the interface, where they adopt an amphiphilic conformation, forming an electrical double layer with their Na+ counterions. Thus, the most important key partners involved in the hydroformylation reaction concentrate at the interface, thereby facilitating the reaction, a process which may be further facilitated upon complexation by CDs. These results point to the importance of adsorption at the liquid-liquid interface in the two-phase hydroformylation reaction of olefins promoted by beta-CDs and provide microscopic pictures of this peculiar region of the solution.
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Affiliation(s)
- N Sieffert
- Laboratoire MSM, UMR CNRS 7177, Institut de Chimie, 4 rue B. Pascal, 67 000 Strasbourg, France
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