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Morris RH. Reactivity umpolung (reversal) of ligands in transition metal complexes. Chem Soc Rev 2024; 53:2808-2827. [PMID: 38353155 DOI: 10.1039/d3cs00979c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
The success and power of homogeneous catalysis derives in large part from the wide choice of transition metal ions and their ligands. This tutorial review introduces examples where the reactivity of a ligand is completely reversed (umpolung) from Lewis basic/nucleophilic to acidic/electrophilic or vice versa on changing the metal and co-ligands. Understanding this phenomenon will assist in the rational design of catalysts and the understanding of metalloenzyme mechanisms. Labelling a metal and ligand with Seebach donor and acceptor labels helps to identify whether a reaction involving the intermolecular attack on the ligand is displaying native reactivity or reactivity umpolung. This has been done for complexes of nitriles, carbonyls, isonitriles, dinitrogen, Fischer carbenes, alkenes, alkynes, hydrides, methyls, methylidenes and alkylidenes, silylenes, oxides, imides/nitrenes, alkylidynes, methylidynes, and nitrides. The electronic influence of the metal and co-ligands is discussed in terms of the energy of (HOMO) d electrons. The energy can be related to the pKLACa (LAC is ligand acidity constant) of the theoretical hydride complexes [H-[M]-L]+ formed by the protonation of pair of valence d electrons on the metal in the [M-L] complex. Preliminary findings indicate that a negative pKLACa indicates that nucleophilic attack by a carbanion or amine on the ligand will likely occur while a positive pKLACa indicates that electrophilic attack by strong acids on the ligand will usually occur when the ligand is nitrile, carbonyl, isonitrile, alkene and η6-arene.
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Affiliation(s)
- Robert H Morris
- Department of Chemistry, University of Toronto, 80 Saint George St., Toronto, Ontario, Canada, M5S3H6.
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2
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Norjmaa G, Ujaque G, Lledós A. Beyond Continuum Solvent Models in Computational Homogeneous Catalysis. Top Catal 2021. [DOI: 10.1007/s11244-021-01520-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AbstractIn homogeneous catalysis solvent is an inherent part of the catalytic system. As such, it must be considered in the computational modeling. The most common approach to include solvent effects in quantum mechanical calculations is by means of continuum solvent models. When they are properly used, average solvent effects are efficiently captured, mainly those related with solvent polarity. However, neglecting atomistic description of solvent molecules has its limitations, and continuum solvent models all alone cannot be applied to whatever situation. In many cases, inclusion of explicit solvent molecules in the quantum mechanical description of the system is mandatory. The purpose of this article is to highlight through selected examples what are the reasons that urge to go beyond the continuum models to the employment of micro-solvated (cluster-continuum) of fully explicit solvent models, in this way setting the limits of continuum solvent models in computational homogeneous catalysis. These examples showcase that inclusion of solvent molecules in the calculation not only can improve the description of already known mechanisms but can yield new mechanistic views of a reaction. With the aim of systematizing the use of explicit solvent models, after discussing the success and limitations of continuum solvent models, issues related with solvent coordination and solvent dynamics, solvent effects in reactions involving small, charged species, as well as reactions in protic solvents and the role of solvent as reagent itself are successively considered.
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Temkin ON. Oxidation of Olefins to Carbonyl Compounds: Modern View of the Classical Reaction. KINETICS AND CATALYSIS 2020. [DOI: 10.1134/s0023158420050122] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Fernandes RA, Jha AK, Kumar P. Recent advances in Wacker oxidation: from conventional to modern variants and applications. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01820a] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Recent developments in the well-known Wacker oxidation process from conventional to modern variants and applications to natural products' synthesis are compiled in this review.
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Affiliation(s)
- Rodney A. Fernandes
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Amit K. Jha
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Praveen Kumar
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
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Abril P, Del Río MP, López JA, Lledós A, Ciriano MA, Tejel C. Inner-Sphere Oxygen Activation Promoting Outer-Sphere Nucleophilic Attack on Olefins. Chemistry 2019; 25:14546-14554. [PMID: 31432579 DOI: 10.1002/chem.201903068] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/19/2019] [Indexed: 01/18/2023]
Abstract
Alkoxylation and hydroxylation reactions of 1,5-cyclooctadiene (cod) in an iridium complex with alcohols and water promoted by the reduction of oxygen to hydrogen peroxide are described. The exo configuration of the OH/OR groups in the products agrees with nucleophilic attack at the external face of the olefin as the key step. The reactions also require the presence of a coordinating protic acid (such as picolinic acid (Hpic)) and involve the participation of a cationic diolefin iridium(III) complex, [Ir(cod)(pic)2 ]+ , which has been isolated. Independently, this cation is also involved in easy alkoxy group exchange reactions, which are very unusual for organic ethers. DFT studies on the mechanism of olefin alkoxylation mediated by oxygen show a low-energy proton-coupled electron-transfer step connecting a superoxide-iridium(II) complex with hydroperoxide-iridium(III) intermediates, rather than peroxide complexes. Accordingly, a more complex reaction, with up to four different products, occurred upon reacting the diolefin-peroxide iridium(III) complex with Hpic. Moreover, such hydroperoxide intermediates are the origin of the regio- and stereoselectivity of the hydroxylation/alkoxylation reactions. If this protocol is applied to the diolefin-rhodium(I) complex [Rh(pic)(cod)], free alkyl ethers ORC8 H11 (R=Me, Et) resulted, and the reaction is enantioselective if a chiral amino acid, such as l-proline, is used instead of Hpic.
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Affiliation(s)
- Paula Abril
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - M Pilar Del Río
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - José A López
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Agustí Lledós
- Departament de Química, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, 08193, Barcelona, Spain
| | - Miguel A Ciriano
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Cristina Tejel
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
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Schroeter F, Strassner T. Understanding Anionic “Ligandless” Palladium Species in the Mizoroki–Heck Reaction. Inorg Chem 2018; 57:5159-5173. [DOI: 10.1021/acs.inorgchem.8b00175] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Felix Schroeter
- Physikalische Organische Chemie, TU Dresden, Bergstrasse 66, 01062 Dresden, Germany
| | - Thomas Strassner
- Physikalische Organische Chemie, TU Dresden, Bergstrasse 66, 01062 Dresden, Germany
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Darabi HR, Rastgar S, Khatamifar E, Aghapoor K, Sayahi H, Firouzi R. Practical and theoretical aspects of Wacker oxidation of tolanophanes: Synthesis and characterization of novel diketonic cyclophanes. Appl Organomet Chem 2017. [DOI: 10.1002/aoc.3812] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Hossein Reza Darabi
- Nano & Organic Synthesis Laboratory; Chemistry & Chemical Engineering Research Center of Iran (CCERCI); Pajohesh Blvd, 17th Km of Tehran-Karaj Highway Tehran 1496813151 Iran
| | - Saeed Rastgar
- Nano & Organic Synthesis Laboratory; Chemistry & Chemical Engineering Research Center of Iran (CCERCI); Pajohesh Blvd, 17th Km of Tehran-Karaj Highway Tehran 1496813151 Iran
| | - Ehsan Khatamifar
- Nano & Organic Synthesis Laboratory; Chemistry & Chemical Engineering Research Center of Iran (CCERCI); Pajohesh Blvd, 17th Km of Tehran-Karaj Highway Tehran 1496813151 Iran
| | - Kioumars Aghapoor
- Nano & Organic Synthesis Laboratory; Chemistry & Chemical Engineering Research Center of Iran (CCERCI); Pajohesh Blvd, 17th Km of Tehran-Karaj Highway Tehran 1496813151 Iran
| | - Hani Sayahi
- Nano & Organic Synthesis Laboratory; Chemistry & Chemical Engineering Research Center of Iran (CCERCI); Pajohesh Blvd, 17th Km of Tehran-Karaj Highway Tehran 1496813151 Iran
| | - Rohoullah Firouzi
- Nano & Organic Synthesis Laboratory; Chemistry & Chemical Engineering Research Center of Iran (CCERCI); Pajohesh Blvd, 17th Km of Tehran-Karaj Highway Tehran 1496813151 Iran
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Imandi V, Nair NN. The Wacker oxidation of allyl alcohol along cyclic–intermediate routes: An ab initio molecular dynamics investigation. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.08.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Vidossich P, Lledós A, Ujaque G. First-Principles Molecular Dynamics Studies of Organometallic Complexes and Homogeneous Catalytic Processes. Acc Chem Res 2016; 49:1271-8. [PMID: 27268523 DOI: 10.1021/acs.accounts.6b00054] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Computational chemistry is a valuable aid to complement experimental studies of organometallic systems and their reactivity. It allows probing mechanistic hypotheses and investigating molecular structures, shedding light on the behavior and properties of molecular assemblies at the atomic scale. When approaching a chemical problem, the computational chemist has to decide on the theoretical approach needed to describe electron/nuclear interactions and the composition of the model used to approximate the actual system. Both factors determine the reliability of the modeling study. The community dedicated much effort to developing and improving the performance and accuracy of theoretical approaches for electronic structure calculations, on which the description of (inter)atomic interactions rely. Here, the importance of the model system used in computational studies is highlighted through examples from our recent research focused on organometallic systems and homogeneous catalytic processes. We show how the inclusion of explicit solvent allows the characterization of molecular events that would otherwise not be accessible in reduced model systems (clusters). These include the stabilization of nascent charged fragments via microscopic solvation (notably, hydrogen bonding), transfer of charge (protons) between distant fragments mediated by solvent molecules, and solvent coordination to unsaturated metal centers. Furthermore, when weak interactions are involved, we show how conformational and solvation properties of organometallic complexes are also affected by the explicit inclusion of solvent molecules. Such extended model systems may be treated under periodic boundary conditions, thus removing the cluster/continuum (or vacuum) boundary, and require a statistical mechanics simulation technique to sample the accessible configurational space. First-principles molecular dynamics, in which atomic forces are computed from electronic structure calculations (namely, density functional theory), is certainly the technique of choice to investigate chemical events in solution. This methodology is well established and thanks to advances in both algorithms and computational resources simulation times required for the modeling of chemical events are nowadays accessible, though the computational requirements use to be high. Specific applications reviewed here include mechanistic studies of the Shilov and Wacker processes, speciation in Pd chemistry, hydrogen bonding to metal centers, and the dynamics of agostic interactions.
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Affiliation(s)
- Pietro Vidossich
- Departament de Química,
Edifici C.n., Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Agustí Lledós
- Departament de Química,
Edifici C.n., Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Gregori Ujaque
- Departament de Química,
Edifici C.n., Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
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Qin S, Dong L, Chen Z, Zhang S, Yin G. Non-redox metal ions can promote Wacker-type oxidations even better than copper(II): a new opportunity in catalyst design. Dalton Trans 2015; 44:17508-15. [PMID: 26390300 DOI: 10.1039/c5dt02612a] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In Wacker oxidation and inspired Pd(ii)/Cu(ii)-catalyzed C-H activations, copper(ii) is believed to serve in re-oxidizing of Pd(0) in the catalytic cycle. Herein we report that non-redox metal ions like Sc(iii) can promote Wacker-type oxidations even better than Cu(ii); both Sc(iii) and Cu(ii) can greatly promote Pd(ii)-catalyzed olefin isomerization in which the redox properties of Cu(ii) are not essential, indicating that the Lewis acid properties of Cu(ii) can play a significant role in Pd(ii)-catalyzed C-H activations in addition to its redox properties. Characterization of catalysts using UV-Vis and NMR indicated that adding Sc(OTf)3 to the acetonitrile solution of Pd(OAc)2 generates a new Pd(ii)/Sc(iii) bimetallic complex having a diacetate bridge which serves as the key active species for Wacker-type oxidation and olefin isomerization. Linkage of trivalent Sc(iii) to the Pd(ii) species makes it more electron-deficient, thus facilitating the coordination of olefin to the Pd(ii) cation. Due to the improved electron transfer from olefin to the Pd(ii) cation, it benefits the nucleophilic attack of water on the olefinic double bond, leading to efficient olefin oxidation. The presence of excess Sc(iii) prevents the palladium(0) black formation, which has been rationalized by the formation of the Sc(iii)H-Pd(ii) intermediate. This intermediate inhibits the reductive elimination of the H-Pd(ii) bond, and facilitates the oxygen insertion to form the HOO-Pd(ii) intermediate, and thus avoids the formation of the inactive palladium(0) black. The Lewis acid promoted Wacker-type oxidation and olefin isomerization demonstrated here may open up a new opportunity in catalyst design for versatile C-H activations.
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Affiliation(s)
- Shuhao Qin
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, Luoyu Road 1037, Wuhan 430074, PR China.
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Imandi V, Nair NN. Can the Absence of Isotope Scrambling in the Wacker Oxidation of Allyl Alcohol Disprove Outer Sphere Hydroxypalladation? J Phys Chem B 2015; 119:11176-83. [DOI: 10.1021/acs.jpcb.5b03099] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Venkataramana Imandi
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Nisanth N. Nair
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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Jiang YY, Zhang Q, Yu HZ, Fu Y. Mechanism of Aldehyde-Selective Wacker-Type Oxidation of Unbiased Alkenes with a Nitrite Co-Catalyst. ACS Catal 2015. [DOI: 10.1021/cs5018776] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuan-Ye Jiang
- Collaborative Innovation Center of Chemistry for Energy Materials, CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Qi Zhang
- Collaborative Innovation Center of Chemistry for Energy Materials, CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Hai-Zhu Yu
- Department of Polymer Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Huasheng Building, Beijing 100083, China
| | - Yao Fu
- Collaborative Innovation Center of Chemistry for Energy Materials, CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
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Kočovský P, Bäckvall JE. The syn/anti-dichotomy in the palladium-catalyzed addition of nucleophiles to alkenes. Chemistry 2015; 21:36-56. [PMID: 25378278 PMCID: PMC4471584 DOI: 10.1002/chem.201404070] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In this review the stereochemistry of palladium-catalyzed addition of nucleophiles to alkenes is discussed, and examples of these reactions in organic synthesis are given. Most of the reactions discussed involve oxygen and nitrogen nucleophiles; the Wacker oxidation of ethylene has been reviewed in detail. An anti-hydroxypalladation in the Wacker oxidation has strong support from both experimental and computational studies. From the reviewed material it is clear that anti-addition of oxygen and nitrogen nucleophiles is strongly favored in intermolecular addition to olefin-palladium complexes even if the nucleophile is coordinated to the metal. On the other hand, syn-addition is common in the case of intramolecular oxy- and amidopalladation as a result of the initial coordination of the internal nucleophile to the metal.
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Affiliation(s)
- Pavel Kočovský
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University10691 Stockholm (Sweden)
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Department of Organic Chemistry, Charles UniversityFlemingovo nám. 2, 16610 Prague 6 (Czech Republic), Hlavova 8 12843 Prague 2 (Czech Republic)
| | - Jan-E Bäckvall
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University10691 Stockholm (Sweden)
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Realistic Simulation of Organometallic Reactivity in Solution by Means of First-Principles Molecular Dynamics. STRUCTURE AND BONDING 2015. [DOI: 10.1007/430_2015_183] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Dong JJ, Browne WR, Feringa BL. Palladium-katalysierte Anti-Markownikoff-Oxidation endständiger Alkene. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201404856] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Dong JJ, Browne WR, Feringa BL. Palladium-catalyzed anti-Markovnikov oxidation of terminal alkenes. Angew Chem Int Ed Engl 2014; 54:734-44. [PMID: 25367376 DOI: 10.1002/anie.201404856] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Indexed: 11/10/2022]
Abstract
The palladium-catalyzed oxidation of alkenes, the Wacker-Tsuji reaction, is undoubtedly a classic in organic synthesis and provides reliable access to methyl ketones from terminal alkenes under mild reaction conditions. Methods that switch the selectivity of the reaction to provide the aldehyde product are desirable because of the access they provide to a valuable functional group, however such methods are elusive. Herein we survey both the methods which have been developed recently in achieving such selectivity and discuss common features and mechanistic insight which offers promise in achieving the goal of a general method for anti-Markovnikov-selective olefin oxidations.
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Affiliation(s)
- Jia Jia Dong
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747AG, Groningen (The Netherlands)
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Stirling A, Nair NN, Lledós A, Ujaque G. Challenges in modelling homogeneous catalysis: new answers from ab initio molecular dynamics to the controversy over the Wacker process. Chem Soc Rev 2014; 43:4940-52. [PMID: 24654007 DOI: 10.1039/c3cs60469a] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We present here a review of the mechanistic studies of the Wacker process stressing the long controversy about the key reaction steps. We give an overview of the previous experimental and theoretical studies on the topic. Then we describe the importance of the most recent Ab Initio Molecular Dynamics (AIMD) calculations in modelling organometallic reactivity in water. As a prototypical example of homogeneous catalytic reactions, the Wacker process poses serious challenges to modelling. The adequate description of the multiple role of the water solvent is very difficult by using static quantum chemical approaches including cluster and continuum solvent models. In contrast, such reaction systems are suitable for AIMD, and by combining with rare event sampling techniques, the method provides reaction mechanisms and the corresponding free energy profiles. The review also highlights how AIMD has helped to obtain a novel understanding of the mechanism and kinetics of the Wacker process.
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Affiliation(s)
- András Stirling
- Institute of Organic Chemistry, Research Centre for Natural Sciences of HAS, Budapest, 1519 Budapest P.O. Box 286, Hungary.
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