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Yadav S, Gupta R. Hydration of Nitriles Catalyzed by Ruthenium Complexes: Role of Dihydrogen Bonding Interactions in Promoting Base-Free Catalysis. Inorg Chem 2022; 61:15463-15474. [PMID: 36137300 DOI: 10.1021/acs.inorgchem.2c02058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ru(II) complexes of amide-phosphine-based tridentate ligands additionally containing pyridine, isoquinoline, and quinoline rings have been synthesized, and their catalytic utility for the selective hydration of nitriles to amides is explored under the base-containing as well as base-free conditions. The chloride-ligated complexes 1-3 exhibited significant catalytic activity in the presence of a base, whereas hydride-ligated complexes 4-6 carried out the hydration of nitrile without the requirement of any base. The mechanistic studies revealed the involvement of [Ru-H] species as the active catalyst in the catalytic cycle. The [Ru-H] species assisted in the polarization of an incoming water molecule through [Ru-H···H-OH] dihydrogen bonding interaction and consequently aided in the attack of a positioned water molecule to a nitrile coordinated to a ruthenium center. Substrate binding studies and kinetic experiments further supported the mechanism. A wide variety of aromatic nitriles containing both electron-withdrawing and electron-releasing groups as well as other substrates including aliphatic nitriles, base-sensitive nitriles, and a few biologically relevant nitriles were employed for the selective hydration.
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Affiliation(s)
- Samanta Yadav
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Rajeev Gupta
- Department of Chemistry, University of Delhi, Delhi 110007, India
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2
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Abstract
To accurately predict the free energy barrier for urea elimination in aqueous solution, we examined the reaction coordinates for the direct and water-assisted elimination pathways, and evaluated the corresponding free energy barriers by using the surface and volume polarization for electrostatics (SVPE) model-based first-principles electronic-structure calculations. Based on the computational results, the water-assisted elimination pathway is dominant for urea elimination in aqueous solution, and the corresponding free energy barrier is 25.3 kcal/mol. The free energy barrier of 25.3 kcal/mol predicted for the dominant reaction pathway of urea elimination in aqueous solution is in good agreement with available experimental kinetic data.
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Silva PL, Silva CM, Guimarães L, Pliego JR. Acid-catalyzed transesterification and esterification in methanol: a theoretical cluster-continuum investigation of the mechanisms and free energy barriers. Theor Chem Acc 2014. [DOI: 10.1007/s00214-014-1591-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Yao M, Tu W, Chen X, Zhan CG. Reaction pathways and free energy profiles for spontaneous hydrolysis of urea and tetramethylurea: unexpected substituent effects. Org Biomol Chem 2014; 11:7595-605. [PMID: 24097048 DOI: 10.1039/c3ob41055b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It has been difficult to directly measure the spontaneous hydrolysis rate of urea and, thus, 1,1,3,3-tetramethylurea (Me4U) was used as a model to determine the "experimental" rate constant for urea hydrolysis. The use of Me4U was based on an assumption that the rate of urea hydrolysis should be 2.8 times that of Me4U hydrolysis because the rate of acetamide hydrolysis is 2.8 times that of N,N-dimethyl-acetamide hydrolysis. The present first-principles electronic-structure calculations on the competing non-enzymatic hydrolysis pathways have demonstrated that the dominant pathway is the neutral hydrolysis via the CN addition for both urea (when pH < ~11.6) and Me4U (regardless of pH), unlike the non-enzymatic hydrolysis of amides where alkaline hydrolysis is dominant. Based on the computational data, the substituent shift of the free energy barrier calculated for the neutral hydrolysis is remarkably different from that for the alkaline hydrolysis, and the rate constant for the urea hydrolysis should be ~1.3 × 10(9)-fold lower than that (4.2 × 10(-12) s(-1)) measured for the Me4U hydrolysis. As a result, the rate enhancement and catalytic proficiency of urease should be 1.2 × 10(25) and 3 × 10(27) M(-1), respectively, suggesting that urease surpasses proteases and all other enzymes in its power to enhance the rate of reaction. All of the computational results are consistent with available experimental data for Me4U, suggesting that the computational prediction for urea is reliable.
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Affiliation(s)
- Min Yao
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China
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5
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Gómez-Bombarelli R, Calle E, Casado J. Mechanisms of lactone hydrolysis in neutral and alkaline conditions. J Org Chem 2013; 78:6868-79. [PMID: 23758295 DOI: 10.1021/jo400258w] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The neutral and base-catalyzed hydrolysis of nine carboxylic acid esters was studied using a hybrid supermolecule-PCM approach including six explicit water molecules. The molecules studied included two linear esters, four β-lactones, two γ-lactones, and one δ-lactone: ethyl acetate and methyl formate, β-propiolactone, β-butyrolactone, β-isovalerolactone, diketene (4-methyleneoxetan-2-one), γ-butyrolactone, 2(5H)-furanone, and δ-valerolactone. DFT and ab initio methods were used to analyze the features of the various possible hydrolysis mechanisms. For all compounds, reasonable to very good qualitative and quantitative agreement with experimental work was found, and evidence is provided to support long-standing hypotheses regarding the role of solvent molecule as a base catalyst. In addition, novel evidence is presented for the existence of an elimination-addition mechanism in the basic hydrolysis of diketene. A parallel work addresses the acid-catalyzed hydrolysis of lactones.
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Affiliation(s)
- Rafael Gómez-Bombarelli
- Department of Physics, School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS, Edinburgh, United Kingdom
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Mihaylov T, Parac-Vogt T, Pierloot K. Unraveling the Mechanisms of Carboxyl Ester Bond Hydrolysis Catalyzed by a Vanadate Anion. Inorg Chem 2012; 51:9619-28. [DOI: 10.1021/ic300620b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Tzvetan Mihaylov
- Chemistry Departement, University of Leuven, Celestijnenlaan 200F, B-3001
Leuven, Belgium
| | - Tatjana Parac-Vogt
- Chemistry Departement, University of Leuven, Celestijnenlaan 200F, B-3001
Leuven, Belgium
| | - Kristine Pierloot
- Chemistry Departement, University of Leuven, Celestijnenlaan 200F, B-3001
Leuven, Belgium
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8
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An accurate theoretical study of energy barriers of alkaline hydrolysis of carboxylic esters. RESEARCH ON CHEMICAL INTERMEDIATES 2012. [DOI: 10.1007/s11164-012-0535-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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9
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Choi SY, Hong YJ, Um IH. Metal Ion Catalysis and Inhibition in Nucleophilic Substitution Reactions of 4-Nitrophenyl Nicotinate and Isonicotinate with Alkali Metal Ethoxides in Anhydrous Ethanol. B KOREAN CHEM SOC 2011. [DOI: 10.5012/bkcs.2011.32.6.1951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Larionov E, Zipse H. Organocatalysis: acylation catalysts. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2011. [DOI: 10.1002/wcms.48] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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11
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Lee JI, Kang JS, Kim SI, Um IH. Effect of Alkali Metal Ions on Alkaline Ethanolysis of 2-Pyridyl and 4-Pyridyl Benzoates in Anhydrous Ethanol. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.10.2929] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Ganguly B, Kesharwani MK, Matković M, Basarić N, Singh A, Mlinarić-Majerski K. Hydrolysis and retro-aldol cleavage of ethyl threo-2-(1-adamantyl)-3-hydroxybutyrate: competing reactions. J PHYS ORG CHEM 2010. [DOI: 10.1002/poc.1793] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Hong YJ, Kim SI, Um IH. Metal Ion Catalysis in Nucleophilic Substitution Reaction of 4-Nitrophenyl Picolinate with Alkali Metal Ethoxides in Anhydrous Ethanol. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.9.2483] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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14
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Limpanuparb T, Punyain K, Tantirungrotechai Y. A DFT investigation of methanolysis and hydrolysis of triacetin. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.theochem.2010.05.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Kim SI, Hwang SJ, Jung EM, Um IH. Kinetics and Mechanism of Alkaline Hydrolysis of Y-Substituted Phenyl Phenyl Carbonates. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.7.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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16
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Solvolysis process of organophosphorus compound P-[2-(dimethylamino)ethyl]-N,N-dimethylphosphonamidic fluoride with simple and α-nucleophiles: a DFT study. Theor Chem Acc 2009. [DOI: 10.1007/s00214-009-0701-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Amos RIJ, Schiesser CH, Smith JA, Yates BF. Nucleophilic Acyl Substitution of Acyl Diimides. J Org Chem 2009; 74:5707-10. [DOI: 10.1021/jo900923m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ruth I. J. Amos
- School of Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
| | - Carl H. Schiesser
- School of Chemistry, The University of Melbourne, Victoria 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Jason A. Smith
- School of Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
| | - Brian F. Yates
- School of Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
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18
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Hao GF, Zhu XL, Ji FQ, Zhang L, Yang GF, Zhan CG. Understanding the mechanism of drug resistance due to a codon deletion in protoporphyrinogen oxidase through computational modeling. J Phys Chem B 2009; 113:4865-75. [PMID: 19284797 DOI: 10.1021/jp807442n] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Protoporphyrinogen oxidase (PPO; EC 1.3.3.4) is the last common enzyme for the enzymatic transformation of protoporphyrinogen-IX to protoporphyrin-IX, which is the key common intermediate leading to heme and chlorophyll. Hence, PPO has been identified as one of the most importance action targets for the treatment of some important diseases including cancer and variegated porphyria (VP). In the agricultural field, PPO inhibitors have been used as herbicides for many years. Recently, a unique drug resistance was found to be associated with a nonactive site residue (Gly210) deletion rather than substitution in A. tuberculatus PPO. In the present study, extensive computational simulations, including homology modeling, molecular dynamics (MD) simulations, and molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) calculations, have been carried out to uncover the detailed molecular mechanism of drug resistance associated with Gly210 deletion. Although Gly210 in the wild-type A. tuberculatus PPO has no direct interaction with the inhibitors, all the computational models and energetic results indicated that Gly210 deletion has great effects on the hydrogen-bonding network and the conformational change of the binding pocket. An interchain hydrogen bond between Gly210 with Ser424, playing an important role in stabilizing the local conformation of the wild-type enzyme, disappeared after Gly210 deletion. As a result, the mutant-type PPO has a lower affinity than the wild-type enzyme, which accounts for the molecular mechanism of drug resistance. The structural and mechanistic insights obtained from the present study provide a new starting point for future rational design of novel PPO inhibitors to overcome drug resistance associated with Gly210 deletion.
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Affiliation(s)
- Ge-Fei Hao
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China
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19
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Chen X, Zhan CG. First-principles determination of molecular conformations of cyclic adenosine 3',5'-monophosphate in gas phase and aqueous solution. J Phys Chem B 2009; 112:16851-9. [PMID: 19367986 DOI: 10.1021/jp806702d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Extensive first-principles electronic structure calculations were performed in this study to explore the possible molecular structures and their concentration distribution of an intracellular second messenger, that is, cyclic adenosine 3',5'-monophosphate (cAMP), and its protonated form (cAMPH) in the gas phase and aqueous solution. The calculations resulted in prediction of four different stable conformers of cAMP and eight different stable conformers of cAMPH and their relative Gibbs free energies in the gas phase and aqueous solution. All of the computational results consistently demonstrate that the predominant conformers of cAMP and cAMPH are always the cAMP-chair-anti and cAMPH-chair2-syn conformers, respectively, in both the gas phase and aqueous solution. It has been demonstrated that the free energy barriers calculated for the intertransformation reactions between different conformers are very low (below approximately 6 kcal/mol) such that the intertransformation reactions between different conformers are very fast so that the concentration distribution of the system can quickly reach the thermodynamic equilibration during the process of binding with a protein. The calculated phenomenological pKa of 3.66 is in good agreement with the experimental pKa of 3.9 reported in literature, suggesting that the computational predictions resulted from this study are reasonable.
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Affiliation(s)
- Xi Chen
- Key Laboratory of Pesticide and Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
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20
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Zheng F, Zhan CG. Structure-and-mechanism-based design and discovery of therapeutics for cocaine overdose and addiction. Org Biomol Chem 2007; 6:836-43. [PMID: 18292872 DOI: 10.1039/b716268e] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
(-)-Cocaine is a widely abused drug and there is currently no available anti-cocaine therapeutic. Promising agents, such as anti-cocaine catalytic antibodies and high-activity mutants of human butyrylcholinesterase (BChE), for therapeutic treatment of cocaine overdose have been developed through structure-and-mechanism-based design and discovery. In particular, a unique computational design strategy based on the modeling and simulation of the rate-determining transition state has been developed and used to design and discover desirable high-activity mutants of BChE. One of the discovered high-activity mutants of BChE has a approximately 456-fold improved catalytic efficiency against (-)-cocaine. The encouraging outcome of the structure-and-mechanism-based design and discovery effort demonstrates that the unique computational design approach based on transition state modeling and simulation is promising for rational enzyme redesign and drug discovery. The general approach of the structure-and-mechanism-based design and discovery may be used to design high-activity mutants of any enzyme or catalytic antibody.
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Affiliation(s)
- Fang Zheng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose Street, Lexington, KY 40536, USA
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21
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Xie D, Xu D, Zhang L, Guo H. Theoretical study of general base-catalyzed hydrolysis of aryl esters and implications for enzymatic reactions. J Phys Chem B 2007; 109:5259-66. [PMID: 16863192 DOI: 10.1021/jp0506181] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, the mechanism of general base-catalyzed hydrolysis of aryl esters is investigated in vacuo with density functional theory and in solutions with a polarized continuum model. The hydrolysis is found to proceed via a concerted mechanism featuring simultaneous addition and elimination steps accompanied by proton transfers, consistent with experimental evidence. Reasonable agreement with measured kinetic isotope effects provides additional validation. It is found that solvation substantially lowers the transition state energy, but has a small effect on the reaction exothermicity. An enzyme oxyanion hole, modeled by an ammonia molecule hydrogen bonded to the acyl carbonyl oxygen, is found to stabilize the near-tetrahedral transition state. Implications of these findings for the hydrolysis step of the dehalogenation reaction catalyzed by 4-chlorobenzoyl-CoA dehalogenase are discussed.
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Affiliation(s)
- Daiqian Xie
- Department of Chemistry, Institute of Theoretical and Computational Chemistry, Nanjing University, Nanjing 210093, People's Republic of China
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22
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Xiong Y, Zhan CG. Theoretical studies of the transition-state structures and free energy barriers for base-catalyzed hydrolysis of amides. J Phys Chem A 2007; 110:12644-52. [PMID: 17107116 PMCID: PMC2892839 DOI: 10.1021/jp063140p] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The transition-state structures and free energy barriers for the rate-determining step (i.e. the formation of a tetrahedral intermediate) of base-catalyzed hydrolysis of a series of amides in aqueous solution have been studied by performing first-principle electronic structure calculations using a hybrid supermolecule-polarizable continuum approach. The calculated results and a revisit of recently reported experimental proton inventory data reveal that the favorable transition-state structure optimized for the tetrahedral intermediate formation of hydroxide ion-catalyzed hydrolysis of formamide may have three solvating water molecules remaining on the attacking hydroxide oxygen and two additional water molecules attached to the carbonyl oxygen of formamide. The calculated results have also demonstrated interesting substituent effects on the optimized transition-state geometries, on the transition-state stabilization, and on the calculated free energy barriers for the base-catalyzed hydrolysis of amides. When some or all of the hydrogen atoms of formamide are replaced by methyl groups, the total number of water molecules hydrogen-bonding with the attacking hydroxide in the transition state decreases from three for formamide to two for N-methylacetamide, N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMA). The larger substituents of the amide hinder the solvent water molecules approaching the attacking hydroxide oxygen in the transition state and, therefore, destabilize the transition-state structure and increase the free energy barrier. By using the optimized most favorable transition-state structures, the calculated free energy barriers, i.e., 21.6 (or 21.7), 22.7, 23.1, and 26.0 kcal/mol for formamide, N-methylacetamide, DMF, and DMA, respectively, are in good agreement with the available experimental free energy barriers, i.e., 21.2, 21.5, 22.6, and 24.1 kcal/mol for formamide, N-methylacetamide, DMF, and DMA, respectively.
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Affiliation(s)
| | - Chang-Guo Zhan
- Corresponding author. Correspondence: Chang-Guo Zhan, Ph.D., Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose Street, Lexington, KY 40536, TEL: 859-323-3943, FAX: 859-323-3575,
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Hori K, Ikenaga Y, Arata K, Takahashi T, Kasai K, Noguchi Y, Sumimoto M, Yamamoto H. Theoretical study on the reaction mechanism for the hydrolysis of esters and amides under acidic conditions. Tetrahedron 2007. [DOI: 10.1016/j.tet.2006.11.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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24
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Andrés GO, Pierini AB, de Rossi RH. Kinetic and Theoretical Studies on the Mechanism of Intramolecular Catalysis in Phenyl Ester Hydrolysis. J Org Chem 2006; 71:7650-6. [PMID: 16995670 DOI: 10.1021/jo061165e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The kinetic study of the hydrolysis reaction of Z-substituted phenyl hydrogen maleates (Z = H, m-CH3, p-CH3, m-Cl, p-Cl and m-CN) was carried out in aqueous solution, and the results were complemented with theoretical studies. Under some experimental conditions, two kinetic processes were observed. One of them was ascribed to maleic anhydride formation and the other to the anhydride hydrolysis. The Brönsted-type plot for the leaving-group dependence was linear with slope beta(lg) = -1. The experimental results are consistent with a mechanism that involves significant bond breaking in the rate-limiting transition state (alpha(lg) = 0.64). Theoretical results for the reaction in the gas phase showed an excellent Brönsted-type dependence with a beta(lg) of -1.03. A tetrahedral intermediate (TI) could not be found through DFT gas-phase studies (B3LYP/6-311+G*). Calculations carried out within a continuous solvation model or with discrete water molecules failed to find a stable TI. With both models, a flat region on the potential-energy surface is found and a tight optimization of the structures led back to starting materials. The theoretical results do not discard the possible existence of an unstable intermediate on the free-energy surface, but the analysis of the whole body of results compared with other acyl transfer reactions lead us to suggest that an enforced concerted mechanism is the most appropriate to describe these reactions.
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Affiliation(s)
- Gabriel O Andrés
- Instituto de Investigaciones en Físico Química de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Organica, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
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Pliego JR. Design of an organocatalyst for ion–molecule SN2 reactions: A new solvent effect on the reaction rate predicted by ab initio calculations. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.molcata.2005.06.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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26
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Zhan CG, Deng SX, Skiba JG, Hayes BA, Tschampel SM, Shields GC, Landry DW. First-principle studies of intermolecular and intramolecular catalysis of protonated cocaine. J Comput Chem 2005; 26:980-6. [PMID: 15880781 PMCID: PMC2875688 DOI: 10.1002/jcc.20241] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We have performed a series of first-principles electronic structure calculations to examine the reaction pathways and the corresponding free energy barriers for the ester hydrolysis of protonated cocaine in its chair and boat conformations. The calculated free energy barriers for the benzoyl ester hydrolysis of protonated chair cocaine are close to the corresponding barriers calculated for the benzoyl ester hydrolysis of neutral cocaine. However, the free energy barrier calculated for the methyl ester hydrolysis of protonated cocaine in its chair conformation is significantly lower than for the methyl ester hydrolysis of neutral cocaine and for the dominant pathway of the benzoyl ester hydrolysis of protonated cocaine. The significant decrease of the free energy barrier, approximately 4 kcal/mol, is attributed to the intramolecular acid catalysis of the methyl ester hydrolysis of protonated cocaine, because the transition state structure is stabilized by the strong hydrogen bond between the carbonyl oxygen of the methyl ester moiety and the protonated tropane N. The relative magnitudes of the free energy barriers calculated for different pathways of the ester hydrolysis of protonated chair cocaine are consistent with the experimental kinetic data for cocaine hydrolysis under physiologic conditions. Similar intramolecular acid catalysis also occurs for the benzoyl ester hydrolysis of (protonated) boat cocaine in the physiologic condition, although the contribution of the intramolecular hydrogen bonding to transition state stabilization is negligible. Nonetheless, the predictability of the intramolecular hydrogen bonding could be useful in generating antibody-based catalysts that recruit cocaine to the boat conformation and an analog that elicited antibodies to approximate the protonated tropane N and the benzoyl O more closely than the natural boat conformer might increase the contribution from hydrogen bonding. Such a stable analog of the transition state for intramolecular catalysis of cocaine benzoyl-ester hydrolysis was synthesized and used to successfully elicit a number of anticocaine catalytic antibodies.
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Affiliation(s)
- Chang-Guo Zhan
- Division of Clinical Pharmacology and Experimental Therapeutics, College of Physicians & Surgeons, Columbia University, 630 West 168th Street, New York, New York 10032, USA.
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Bazzicalupi C, Bencini A, Berni E, Di Vaira M. Reaction pathways for Zn(II)-catalyzed carboxylic acid esters hydrolysis. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2004.07.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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29
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Fox JM, Dmitrenko O, Liao LA, Bach RD. Computational studies of nucleophilic substitution at carbonyl carbon: the S(N)2 mechanism versus the tetrahedral intermediate in organic synthesis. J Org Chem 2004; 69:7317-28. [PMID: 15471486 DOI: 10.1021/jo049494z] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A theoretical study specifically addresses the question of whether nucleophilic addition to the carbonyl groups of acid chlorides, esters, and anhydrides involves an addition-elimination pathway or proceeds by a concerted S(N)2-like mechanism in the absence of the generally assumed tetrahedral intermediate. Density functional calculations [B3LYP/6-31+G(d,p)] establish that chloride ion exchange reactions with both formyl and acetyl chloride proceed by a pi attack on the C=O bond. No discernible tetrahedral intermediate typical of an addition-elimination pathway was found in either case. While a tetrahedral intermediate does exist for the addition of fluoride ion to (Cl)(2)C=O, halide exchange of LiCl with both ClFC=O and (Cl)(2)C=O also proceeds by a concerted S(N)2-like pathway. The formation of a tetrahedral intermediate from the addition of methanol to acetyl chloride is slightly exothermic (4.4 kcal/mol). The ion-dipole complex of methanol weakly bonded to the carbonyl carbon of protonated acetyl chloride is stabilized by 13.8 kcal/mol but does not collapse to a tetrahedral intermediate. When four CH(3)OH molecules are H-bonded to protonated acetyl chloride, a tetrahedral intermediate is not completely formed and this solvated complex more closely resembles the precursor to an S(N)1-type ionization of Cl(-). With six H-bonding methanol molecules, a methanol adds to the carbonyl carbon and a proton relay occurs with formation of a tetrahedral-like structure that immediately loses chloride ion in an S(N)1-like solvolysis. These results corroborate earlier suggestions (Bentley et al. J. Org. Chem. 1996, 61, 7927) that the methanolysis of acetyl chloride does not proceed through the generally assumed addition-elimination pathway with a discrete tetrahedral intermediate but is consistent with ionization of Cl(-). The reaction of methoxide ion with methyl acetate proceeds via a multiple-well energy surface and involves the intermediacy of an asymmetrical species with differing C-OMe bond lengths. Models of synthetic applications of acyl transfer reactions involving anhydrides that form N-acyloxazolidinones also proceed by a concerted S(N)2-type pathway even with the carboxylate leaving group. Concerted transition states were observed for the reactions of each enantiomer of a 1,3-diphenylcycloprop-2-ene carboxylic anhydride by S-3-lithio-4-phenyloxazolidinone. Despite close structural similarities between the diastereomeric transition states, the relative energies correlated closely with the experimental results.
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Affiliation(s)
- Joseph M Fox
- Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19803, USA
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Xiong Y, Zhan CG. Reaction Pathways and Free Energy Barriers for Alkaline Hydrolysis of Insecticide 2-Trimethylammonioethyl Methylphosphonofluoridate and Related Organophosphorus Compounds: Electrostatic and Steric Effects. J Org Chem 2004; 69:8451-8. [PMID: 15549820 DOI: 10.1021/jo0487597] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reaction pathways and free energy barriers for alkaline hydrolysis of the highly neurotoxic insecticide 2-trimethylammonioethyl methylphosphonofluoridate and related organophosphorus compounds were studied by performing first-principles electronic structure calculations on representative methylphosphonofluoridates, (RO)CH3P(O)F, in which R = CH2CH2N+(CH3)3, CH3, CH2CH2C(CH3)3, CH2CH2CH(CH3)2, CH(CH3)CH2N+(CH3)3, and CH(CH3)CH2N(CH3)2. The dominant reaction pathway was found to be associated with a transition state in which the attacking nucleophile OH- and the leaving group F- are positioned on opposite sides of the plane formed by the three remaining atoms attached to the phosphorus in order to minimize the electrostatic repulsion between these two groups. The free energy barriers calculated for the rate-determining step of the dominant pathway are 12.5 kcal/mol when R = CH2CH2N+(CH3)3, 15.5 kcal/mol when R = CH3, 17.9 kcal/mol when R = CH2CH2C(CH3)3, 16.5 kcal/mol when R = CH2CH2CH(CH3)2, 13.4 kcal/mol when R = CH(CH3)CH2N+(CH3)3, and 18.7 kcal/mol when R = CH(CH(3))CH(2)N(CH(3))(2). The calculated free energy barriers are in good agreement with available experimentally derived activation free energies, i.e. 14.7 kcal/mol when R = CH(3), 13.4 kcal/mol when R = CH2CH2N+(CH3)3, and 13.9 kcal/mol when R = CH(CH3)CH2N+(CH3)3. A detailed analysis of the calculated energetic results and available experimental data suggests that the net charge of the molecule (M) being hydrolyzed is a prominent factor affecting the free energy barrier (DeltaG) for the alkaline hydrolysis of phosphodiesters, phosphonofluoridates, and related organophosphorus compounds. The electrostatic interactions between the attacking nucleophile OH- and the molecule M being hydrolyzed favor such an order of the free energy barrier: DeltaG(M(+)+OH-) < DeltaG(M0+OH-) < DeltaG(M(-)+OH-), where M+, M0, and M- represent the cationic, neutral, and anionic molecules, respectively. The change of the substituent R in (RO)CH(3)P(O)F from CH3 to CH2CH2N+(CH3)3 is associated with both the electrostatic and steric effects on the free energy barrier, but the electrostatic effect dominates the substituent shift of the free energy barrier. This helps to better understand why the alkaline hydrolysis of (RO)CH3P(O)F with R = CH2CH2N+(CH3)3 and CH(CH3)CH2N+(CH3)3 is significantly faster than that with R = CH3. The effect of electrostatic interaction also helps to understand why the rate constants for the alkaline hydrolysis of phosphodiesters, such as intramolecular second messenger adenosine 3',5'-phosphate (cAMP), are generally smaller than those for the alkaline hydrolysis of the phosphonofluoridates and related phosphotriesters.
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Affiliation(s)
- Ying Xiong
- Key Laboratory of Pesticide & Chemical Biology of the Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China
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Chen X, Zhan CG. Theoretical Determination of Activation Free Energies for Alkaline Hydrolysis of Cyclic and Acyclic Phosphodiesters in Aqueous Solution. J Phys Chem A 2004. [DOI: 10.1021/jp049938v] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xi Chen
- College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China and Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 907 Rose Street, Lexington, Kentucky 40536
| | - Chang-Guo Zhan
- College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China and Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 907 Rose Street, Lexington, Kentucky 40536
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Chen X, Zhan CG. Fundamental Reaction Pathways and Free-Energy Barriers for Ester Hydrolysis of Intracellular Second-Messenger 3‘,5‘-Cyclic Nucleotide. J Phys Chem A 2004. [DOI: 10.1021/jp0371635] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Xi Chen
- College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China, and Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 907 Rose Street, Lexington, Kentucky 40536
| | - Chang-Guo Zhan
- College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China, and Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 907 Rose Street, Lexington, Kentucky 40536
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Pliego, JR, Riveros JM. Free Energy Profile of the Reaction between the Hydroxide Ion and Ethyl Acetate in Aqueous and Dimethyl Sulfoxide Solutions: A Theoretical Analysis of the Changes Induced by the Solvent on the Different Reaction Pathways. J Phys Chem A 2004. [DOI: 10.1021/jp036955w] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Josefredo R. Pliego,
- Departamento de Química, Universidade Federal de Santa Catarina, CEP 88040-900 Florianópolis, SC, Brazil, and Instituto de Química, Universidade de São Paulo, Avenida Lineu Prestes 748, CEP 05508-900 São Paulo, SP, Brazil
| | - José M. Riveros
- Departamento de Química, Universidade Federal de Santa Catarina, CEP 88040-900 Florianópolis, SC, Brazil, and Instituto de Química, Universidade de São Paulo, Avenida Lineu Prestes 748, CEP 05508-900 São Paulo, SP, Brazil
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34
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WANG MAWLING, LAM GINGKUN. HYDROLYSIS OF ETHYL-2-BROMOISOBUTYRATE ESTER IN AN ALKALINE SOLUTION. CHEM ENG COMMUN 2004. [DOI: 10.1080/00986440490261863] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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35
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Zhan CG, Zheng F, Landry DW. Fundamental reaction mechanism for cocaine hydrolysis in human butyrylcholinesterase. J Am Chem Soc 2003; 125:2462-74. [PMID: 12603134 PMCID: PMC2893393 DOI: 10.1021/ja020850+] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Butyrylcholinesterase (BChE)-cocaine binding and the fundamental pathway for BChE-catalyzed hydrolysis of cocaine have been studied by molecular modeling, molecular dynamics (MD) simulations, and ab initio calculations. Modeling and simulations indicate that the structures of the prereactive BChE/substrate complexes for (-)-cocaine and (+)-cocaine are all similar to that of the corresponding prereactive BChE/butyrylcholine (BCh) complex. The overall binding of BChE with (-)-cocaine and (+)-cocaine is also similar to that proposed with butyrylthiocholine and succinyldithiocholine, i.e., (-)- or (+)-cocaine first slides down the substrate-binding gorge to bind to Trp-82 and stands vertically in the gorge between Asp-70 and Trp-82 (nonprereactive complex) and then rotates to a position in the catalytic site within a favorable distance for nucleophilic attack and hydrolysis by Ser-198 (prereactive complex). In the prereactive complex, cocaine lies horizontally at the bottom of the gorge. The fundamental catalytic hydrolysis pathway, consisting of acylation and deacylation stages similar to those for ester hydrolysis by other serine hydrolases, was proposed on the basis of the simulated prereactive complex and confirmed theoretically by ab initio reaction coordinate calculations. Both the acylation and deacylation follow a double-proton-transfer mechanism. The calculated energetic results show that within the chemical reaction process the highest energy barrier and Gibbs free energy barrier are all associated with the first step of deacylation. The calculated ratio of the rate constant (k(cat)) for the catalytic hydrolysis to that (k(0)) for the spontaneous hydrolysis is approximately 9.0 x 10(7). The estimated k(cat)/k(0) value of approximately 9.0 x 10(7) is in excellent agreement with the experimentally derived k(cat)/k(0) value of approximately 7.2 x 10(7) for (+)-cocaine, whereas it is approximately 2000 times larger than the experimentally derived k(cat)/k(0) value of approximately 4.4 x 10(4) for (-)-cocaine. All of the results suggest that the rate-determining step of the BChE-catalyzed hydrolysis of (+)-cocaine is the first step of deacylation, whereas for (-)-cocaine the change from the nonprereactive complex to the prereactive complex is rate-determining and has a Gibbs free energy barrier higher than that for the first step of deacylation by approximately 4 kcal/mol. A further analysis of the structural changes from the nonprereactive complex to the prereactive complex reveals specific amino acid residues hindering the structural changes, providing initial clues for the rational design of BChE mutants with improved catalytic activity for (-)-cocaine.
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Affiliation(s)
- Chang-Guo Zhan
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032
- To whom correspondence should be addressed. Current address: Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536.
| | - Fang Zheng
- Department of Computer Science and Engineering, Washington State University, 2710 University Drive, Richland, Washington 99352
| | - Donald W. Landry
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032
- To whom correspondence should be addressed. Current address: Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536.
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36
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Zhan CG, Dixon DA. A Density Functional Theory Approach to the Development of Q−e Parameters for the Prediction of Reactivity in Free-Radical Copolymerizations. J Phys Chem A 2002. [DOI: 10.1021/jp020497u] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chang-Guo Zhan
- William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K1-83, P.O. Box 999, Richland, Washington 99352
| | - David A. Dixon
- William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K1-83, P.O. Box 999, Richland, Washington 99352
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37
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Mata-Segreda JF. Hydroxide as general base in the saponification of ethyl acetate. J Am Chem Soc 2002; 124:2259-62. [PMID: 11878979 DOI: 10.1021/ja011931t] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The second-order rate constant for the saponification of ethyl acetate at 30.0 degrees C in H(2)O/D(2)O mixtures of deuterium atom fraction n (a proton inventory experiment) obeys the relation k(2)(n) = 0.122 s(-1) M(-1) (1 - n + 1.2n) (1 - n + 0.48n)/(1 - n + 1.4n) (1 - n + 0.68n)(3). This result is interpreted as a process where formation of the tetrahedral intermediate is the rate-determining step and the transition-state complex is formed via nucleophilic interaction of a water molecule with general-base assistance from hydroxide ion, opposite to the direct nucleophilic collision commonly accepted. This mechanistic picture agrees with previous heavy-atom kinetic isotope effect data of Marlier on the alkaline hydrolysis of methyl formate.
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Pliego JR, Riveros JM. Theoretical Study of the Gas-Phase Reaction of Fluoride and Chloride Ions with Methyl Formate. J Phys Chem A 2001. [DOI: 10.1021/jp0114081] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Josefredo R. Pliego
- Instituto de Química, Universidade de São Paulo, Caixa Postal 26077, CEP 05513-970 São Paulo, SP, Brazil
| | - José M. Riveros
- Instituto de Química, Universidade de São Paulo, Caixa Postal 26077, CEP 05513-970 São Paulo, SP, Brazil
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Zhan CG, Landry DW. Theoretical Studies of Competing Reaction Pathways and Energy Barriers for Alkaline Ester Hydrolysis of Cocaine. J Phys Chem A 2001. [DOI: 10.1021/jp0023157] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chang-Guo Zhan
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032
| | - Donald W. Landry
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032
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40
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Pliego JR, Riveros JM. The gas-phase reaction between hydroxide ion and methyl formate: a theoretical analysis of the energy surface and product distribution. Chemistry 2001; 7:169-75. [PMID: 11205008 DOI: 10.1002/1521-3765(20010105)7:1<169::aid-chem169>3.0.co;2-e] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The potential energy surface for the prototype solvent-free ester hydrolysis reaction: OH- +HCOOCH3 --> products has been characterized by high level ab initio calculations of MP4/6-311 + G(2df,2p)//MP2/6-31 + G(d) quality. These calculations reveal that the approach of an OH- ion leads to the formation of two distinct ion-molecule complexes: 1) the MS1 species with the hydroxide ion hydrogen bonded to the methyl group of the ester, and 2) the MS4 moiety resulting from proton abstraction of the formyl hydrogen by the hydroxide ion and formation of a three-body complex of water, methoxide ion and carbon monoxide. The first complex reacts to generate formate anion and methanol products through the well known B(AC)2 and S(N)2 mechanisms. RRKM calculations predict that these pathways will occur with a relative contribution of 85% and 15% at 298.15 K, in excellent agreement with experimentally measured values of 87% and 13%, respectively. The second complex reacts by loss of carbon monoxide to yield the water-methoxide complex through a single minimum potential surface and is the preferred pathway in the gas-phase. This water-methoxide adduct can further dissociate if the reactants have excess energy. These results provide clear evidence that the preferred pathways for ester hydrolysis in solution are dictated by solvation of the hydroxide ion.
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Affiliation(s)
- J R Pliego
- Instituto de Química, University of São Paulo, CEP, Brazil.
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41
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Lee I, Kim CK, Li HG, Sohn CK, Kim CK, Lee HW, Lee BS. Acyl-Transfer Mechanisms Involving Various Acyl Functional Groups: >XY with X = C, S, P and Y = O, S. J Am Chem Soc 2000. [DOI: 10.1021/ja001814i] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ikchoon Lee
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
| | - Chang Kon Kim
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
| | - Hong Guang Li
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
| | - Chang Kook Sohn
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
| | - Chan Kyung Kim
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
| | - Hai Whang Lee
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
| | - Bon-Su Lee
- Contribution from the Department of Chemistry, Inha University, Inchon 402-751, Korea, and Department of Chemistry Education, Chonnam University, Kwangju 500-757, Korea
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42
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Zhan CG, Landry DW, Ornstein RL. Energy Barriers for Alkaline Hydrolysis of Carboxylic Acid Esters in Aqueous Solution by Reaction Field Calculations. J Phys Chem A 2000. [DOI: 10.1021/jp001459i] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chang-Guo Zhan
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032 and the Pacific Northwest National Laboratory, Battelle-Northwest, Environmental Technology Division, Mailstop K2-21, Richland, Washington 99352
| | - Donald W. Landry
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032 and the Pacific Northwest National Laboratory, Battelle-Northwest, Environmental Technology Division, Mailstop K2-21, Richland, Washington 99352
| | - Rick L. Ornstein
- Department of Medicine, College of Physician & Surgeons, Columbia University, New York, New York 10032 and the Pacific Northwest National Laboratory, Battelle-Northwest, Environmental Technology Division, Mailstop K2-21, Richland, Washington 99352
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43
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Zhan CG, Landry DW, Ornstein RL. Reaction Pathways and Energy Barriers for Alkaline Hydrolysis of Carboxylic Acid Esters in Water Studied by a Hybrid Supermolecule-Polarizable Continuum Approach. J Am Chem Soc 2000. [DOI: 10.1021/ja9937932] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Chang-Guo Zhan
- Contribution from the Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, New York 10032, and the Pacific Northwest National Laboratory, Battelle-Northwest, Environmental Technology Division, Mailstop K2-21, Richland, Washington 99352
| | - Donald W. Landry
- Contribution from the Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, New York 10032, and the Pacific Northwest National Laboratory, Battelle-Northwest, Environmental Technology Division, Mailstop K2-21, Richland, Washington 99352
| | - Rick L. Ornstein
- Contribution from the Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, New York 10032, and the Pacific Northwest National Laboratory, Battelle-Northwest, Environmental Technology Division, Mailstop K2-21, Richland, Washington 99352
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