1
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Sahoo J, Panda J, Giri S, Sahoo G. Concept-Driven Chemoselective O/N-Derivatization of Prolinol: A Bee-Line Approach to Access Organocatalysts. J Org Chem 2023. [PMID: 37402179 DOI: 10.1021/acs.joc.3c00992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2023]
Abstract
An investigation into the sensitivity of reaction conditions to a highly utilized protocol has been reported, wherein the mono-Boc functionalization of prolinol could be controlled for the exclusive synthesis of either N-Boc, O-Boc, or oxazolidinone derivatives. Mechanistic investigation revealed that the elementary steps could possibly be controlled by (a) a requisite base to recognize the differently acidic sites (NH and OH) for the formation of the conjugate base, which reacts with the electrophile, and (b) the difference in nucleophilicity of the conjugate basic sites. Herein, a successful chemoselective functionalization of the nucleophilic sites of prolinol by employing a suitable base is reported. This has been achieved by exploiting the relative acidity difference of NH and OH along with the reversed nucleophilicity of the corresponding conjugate bases N- and O-. This protocol has also been used for the synthesis of several O-functionalized prolinol derived organocatalysts, few of which have been newly reported.
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Affiliation(s)
- Jigyansa Sahoo
- Organocatalysis and Synthesis Laboratory, Department of Chemistry, National Institute of Technology Rourkela, Rourkela 769008, Odisha, India
| | - Jeetendra Panda
- Organocatalysis and Synthesis Laboratory, Department of Chemistry, National Institute of Technology Rourkela, Rourkela 769008, Odisha, India
| | - Santanab Giri
- School of Applied Science and Humanities, Haldia Institute of Technology, Haldia 721657, West Bengal, India
| | - Gokarneswar Sahoo
- Organocatalysis and Synthesis Laboratory, Department of Chemistry, National Institute of Technology Rourkela, Rourkela 769008, Odisha, India
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2
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Cukrowski I, Dhimba G, Riley DL. A Molecular-Wide and Electron Density-Based Approach in Exploring Chemical Reactivity and Explicit Dimethyl Sulfoxide (DMSO) Solvent Molecule Effects in the Proline Catalyzed Aldol Reaction. Molecules 2022; 27:molecules27030962. [PMID: 35164227 PMCID: PMC8839911 DOI: 10.3390/molecules27030962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/19/2022] [Accepted: 01/24/2022] [Indexed: 02/05/2023] Open
Abstract
Modelling of the proline (1) catalyzed aldol reaction (with acetone 2) in the presence of an explicit molecule of dimethyl sulfoxide (DMSO) (3) has showed that 3 is a major player in the aldol reaction as it plays a double role. Through strong interactions with 1 and acetone 2, it leads to a significant increase of energy barriers at transition states (TS) for the lowest energy conformer 1a of proline. Just the opposite holds for the higher energy conformer 1b. Both the ‘inhibitor’ and ‘catalyst’ mode of activity of DMSO eliminates 1a as a catalyst at the very beginning of the process and promotes the chemical reactivity, hence catalytic ability of 1b. Modelling using a Molecular-Wide and Electron Density-based concept of Chemical Bonding (MOWED-CB) and the Reaction Energy Profile–Fragment Attributed Molecular System Energy Change (REP-FAMSEC) protocol has shown that, due to strong intermolecular interactions, the HN-C-COOH (of 1), CO (of 2), and SO (of 3) fragments drive a chemical change throughout the catalytic reaction. We strongly advocate exploring the pre-organization of molecules from initially formed complexes, through local minima to the best structures suited for a catalytic process. In this regard, a unique combination of MOWED-CB with REP-FAMSEC provides an invaluable insight on the potential success of a catalytic process, or reaction mechanism in general. The protocol reported herein is suitable for explaining classical reaction energy profiles computed for many synthetic processes.
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3
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Shajahan R, Sarang R, Saithalavi A. Polymer Supported Proline-Based Organocatalysts in Asymmetric Aldol Reactions: A Review. CURRENT ORGANOCATALYSIS 2022. [DOI: 10.2174/2213337209666220112094231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The use of proline-based organocatalysts has acquired significant importance in organic synthesis, especially in enantioselective synthesis. Proline and its derivatives are proven to be quite effective chiral organocatalysts for a variety of transformations including the aldol reaction, which is considered as one of the important C-C bond forming reactions in organic synthesis. The use of chiral organocatalysts has several advantages over its metal-mediated analogues. Subsequently, a large number of highly efficient proline-based organocatalysts including polymer-supported chiral analogues have been identified for aldol reaction. The use of polymer-supported organocatalysts exhibited remarkable stability under the reaction conditions and offered the best results particularly in terms of its recyclability and reusability. These potential benefits along with its economic and green chemistry advantages have led to the search for many polymer-supported proline catalysts. In this review, recent developments in exploring various polymer immobilized proline-based chiral organocatalysts for asymmetric aldol reactions are described.
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Affiliation(s)
- Rubina Shajahan
- School of Chemical Sciences, Mahatma Gandhi University, Kottayam, Kerala, India-686560
| | - Rithwik Sarang
- Institute for Integrated Programmes and Research in Basic Sciences (IIRBS), Mahatma Gandhi University, Kottayam, Kerala, India-686560
| | - Anas Saithalavi
- School of Chemical Sciences, Mahatma Gandhi University, Kottayam, Kerala, India-686560
- Institute for Integrated Programmes and Research in Basic Sciences (IIRBS), Mahatma Gandhi University, Kottayam, Kerala, India-686560
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4
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Domb I, Lustosa DM, Milo A. Secondary-sphere modification in proline catalysis: Old friend, new connection. Chem Commun (Camb) 2022; 58:1950-1953. [DOI: 10.1039/d1cc05589e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, we exploit our strategy of in situ secondary-sphere modification of organocatalysts to improve the reactivity and selectivity of amino catalysts. Herein, the carboxylic acid moiety of proline...
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5
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Sunoj RB. Coming of Age of Computational Chemistry from a Resilient Past to a Promising Future. Isr J Chem 2021. [DOI: 10.1002/ijch.202100106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Raghavan B. Sunoj
- Department of Chemistry Indian Institute of Technology Bombay, Powai Mumbai 400076 India
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6
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Hartmann PE, Lazzarotto M, Pletz J, Tanda S, Neu P, Goessler W, Kroutil W, Boese AD, Fuchs M. Mechanistic Studies of the TRIP-Catalyzed Allylation with Organozinc Reagents. J Org Chem 2020; 85:9672-9679. [PMID: 32648755 PMCID: PMC7418105 DOI: 10.1021/acs.joc.0c00992] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
3,3-Bis(2,4,6-triisopropylphenyl)-1,1-binaphthyl-2,2-diyl
hydrogenphosphate
(TRIP) catalyzes the asymmetric allylation of aldehydes with organozinc
compounds, leading to highly valuable structural motifs, like precursors
to lignan natural products. Our previously reported mechanistic proposal
relies on two reaction intermediates and requires further investigation
to really understand the mode of action and the origins of stereoselectivity.
Detailed ab initio calculations, supported by experimental data, render
a substantially different mode of action to the allyl boronate congener.
Instead of a Brønsted acid-based catalytic activation, the chiral
phosphate acts as a counterion for the Lewis acidic zinc ion, which
provides the activation of the aldehyde.
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Affiliation(s)
- Peter E Hartmann
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe.,Physical and Theoretical Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/IV, 8010 Graz, Austria, Europe
| | - Mattia Lazzarotto
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - Jakob Pletz
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - Stefan Tanda
- Analytical Chemistry, Institute of Chemistry, University of Graz, Universitätsplatz 1/I, 8010 Graz, Austria, Europe
| | - Philipp Neu
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - Walter Goessler
- Analytical Chemistry, Institute of Chemistry, University of Graz, Universitätsplatz 1/I, 8010 Graz, Austria, Europe
| | - Wolfgang Kroutil
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - A Daniel Boese
- Physical and Theoretical Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/IV, 8010 Graz, Austria, Europe
| | - Michael Fuchs
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
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7
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Rufino VC, Pliego JR. Is the iminium ion mechanism viable in the piperidine-catalyzed 1,4-conjugate addition reaction of nitroalkanes to α,β-unsaturated ketones? COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2019.112541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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8
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Kwon DH, Fuller JT, Kilgore UJ, Sydora OL, Bischof SM, Ess DH. Computational Transition-State Design Provides Experimentally Verified Cr(P,N) Catalysts for Control of Ethylene Trimerization and Tetramerization. ACS Catal 2018. [DOI: 10.1021/acscatal.7b04026] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Doo-Hyun Kwon
- Department
of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Jack T. Fuller
- Department
of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Uriah J. Kilgore
- Research and Technology, Chevron Phillips Chemical Company LP, 1862 Kingwood Drive, Kingwood, Texas 77339, United States
| | - Orson L. Sydora
- Research and Technology, Chevron Phillips Chemical Company LP, 1862 Kingwood Drive, Kingwood, Texas 77339, United States
| | - Steven M. Bischof
- Research and Technology, Chevron Phillips Chemical Company LP, 1862 Kingwood Drive, Kingwood, Texas 77339, United States
| | - Daniel H. Ess
- Department
of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
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9
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Shu S, Liu Z, Li Y, Ke Z, Liu Y. Diastereoselectivity in a cyclic secondary amine catalyzed asymmetric Mannich reaction: a model rationalization from DFT studies. Org Chem Front 2018. [DOI: 10.1039/c8qo00424b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
DFT studies revealed the detailed structure stereoselectivity relationship for cyclic secondary amine catalyzed asymmetric Mannich reactions.
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Affiliation(s)
- Siwei Shu
- School of Chemical Engineering and Light Industry
- Guangdong University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- P. R. China
| | - Zhao Liu
- School of Chemistry
- School of Materials Science & Engineering
- PCFM Lab
- Sun Yat-sen University
- Guangzhou 510275
| | - Yukui Li
- School of Chemistry
- School of Materials Science & Engineering
- PCFM Lab
- Sun Yat-sen University
- Guangzhou 510275
| | - Zhuofeng Ke
- School of Chemistry
- School of Materials Science & Engineering
- PCFM Lab
- Sun Yat-sen University
- Guangzhou 510275
| | - Yan Liu
- School of Chemical Engineering and Light Industry
- Guangdong University of Technology
- Higher Education Mega Center
- Guangzhou 510006
- P. R. China
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10
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Dalessandro EV, Collin HP, Guimarães LGL, Valle MS, Pliego JR. Mechanism of the Piperidine-Catalyzed Knoevenagel Condensation Reaction in Methanol: The Role of Iminium and Enolate Ions. J Phys Chem B 2017; 121:5300-5307. [DOI: 10.1021/acs.jpcb.7b03191] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Ellen V. Dalessandro
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, 36301-160, São João del-Rei, MG, Brazil
| | - Hugo P. Collin
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, 36301-160, São João del-Rei, MG, Brazil
| | - Luiz Gustavo L. Guimarães
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, 36301-160, São João del-Rei, MG, Brazil
| | - Marcelo S. Valle
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, 36301-160, São João del-Rei, MG, Brazil
| | - Josefredo R. Pliego
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, 36301-160, São João del-Rei, MG, Brazil
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11
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Doney AC, Rooks BJ, Lu T, Wheeler SE. Design of Organocatalysts for Asymmetric Propargylations through Computational Screening. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02366] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Analise C. Doney
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Benjamin J. Rooks
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Tongxiang Lu
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Steven E. Wheeler
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
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12
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Sunoj RB. Transition State Models for Understanding the Origin of Chiral Induction in Asymmetric Catalysis. Acc Chem Res 2016; 49:1019-28. [PMID: 27101013 DOI: 10.1021/acs.accounts.6b00053] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In asymmetric catalysis, a chiral catalyst bearing chiral center(s) is employed to impart chirality to developing stereogenic center(s). A rich and diverse set of chiral catalysts is now available in the repertoire of synthetic organic chemistry. The most recent trends point to the emergence of axially chiral catalysts based on binaphthyl motifs, in particular, BINOL-derived phosphoric acids and phosphoramidites. More fascinating ideas took shape in the form of cooperative multicatalysis wherein organo- and transition-metal catalysts are made to work in concert. At the heart of all such manifestations of asymmetric catalysis, classical or contemporary, is the stereodetermining transition state, which holds a perennial control over the stereochemical outcome of the catalytic process. Delving one step deeper, one would find that the origin of the stereoselectivity is delicately dependent on the relative stabilization of one transition state, responsible for the formation of the predominant stereoisomer, over the other transition state for the minor stereoisomer. The most frequently used working hypothesis to rationalize the experimentally observed stereoselectivity places an undue emphasis on steric factors and tends to regard the same as the origin of facial discrimination between the prochiral faces of the reacting partners. In light of the increasing number of asymmetric catalysts that rely on hydrogen bonding as well as other weak non-covalent interactions, it is important to take cognizance of the involvement of such interactions in the sterocontrolling transition states. Modern density functional theories offer a pragmatic and effective way to capture non-covalent interactions in transition states. Aided by the availability of such improved computational tools, it is quite timely that the molecular origin of stereoselectivity is subjected to more intelligible analysis. In this Account, we describe interesting molecular insights into the stereocontrolling transition states of five reaction types, three of which provide access to chiral quaternary carbon atoms. While each reaction has its own utility and interest, the focus of our research has been on the mechanism and the origin of the enantio- and diastereoselectivity. In all of the examples, such as asymmetric diamination, sulfoxidation, allylation, and Wacker-type ring expansion, the role played by non-covalent interactions in the stereocontrolling transition states has been identified as crucial. The transfer of the chiral information from the chiral catalyst to the product is identified as taking place through a series of non-covalent interactions between the catalyst and a given position/orientation of the substrate in the chiral environment offered by the axially chiral catalyst. The molecular insights enunciated herein allude to abundant opportunities for rational modifications of the present generation of catalysts and the choice of substrates in these as well as related families of reactions. It is our intent to propose that the domain of asymmetric catalysis could enjoy additional benefits by having knowledge of the vital stereoelectronic interactions in the stereocontrolling transition states.
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Affiliation(s)
- Raghavan B. Sunoj
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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13
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Wheeler SE, Seguin TJ, Guan Y, Doney AC. Noncovalent Interactions in Organocatalysis and the Prospect of Computational Catalyst Design. Acc Chem Res 2016; 49:1061-9. [PMID: 27110641 DOI: 10.1021/acs.accounts.6b00096] [Citation(s) in RCA: 259] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Noncovalent interactions are ubiquitous in organic systems, and can play decisive roles in the outcome of asymmetric organocatalytic reactions. Their prevalence, combined with the often subtle line separating favorable dispersion interactions from unfavorable steric interactions, often complicates the identification of the particular noncovalent interactions responsible for stereoselectivity. Ultimately, the stereoselectivity of most organocatalytic reactions hinges on the balance of both favorable and unfavorable noncovalent interactions in the stereocontrolling transition state (TS). In this Account, we provide an overview of our attempts to understand the role of noncovalent interactions in organocatalyzed reactions and to develop new computational tools for organocatalyst design. Following a brief discussion of noncovalent interactions involving aromatic rings and the associated challenges capturing these effects computationally, we summarize two examples of chiral phosphoric acid catalyzed reactions in which noncovalent interactions play pivotal, although somewhat unexpected, roles. In the first, List's catalytic asymmetric Fischer indole reaction, we show that both π-stacking and CH/π interactions of the substrate with the 3,3'-aryl groups of the catalyst impact the stability of the stereocontrolling TS. However, these noncovalent interactions oppose each other, with π-stacking interactions stabilizing the TS leading to one enantiomer and CH/π interactions preferentially stabilizing the competing TS. Ultimately, the CH/π interactions dominate and, when combined with hydrogen bonding interactions, lead to preferential formation of the observed product. In the second example, a series of phosphoric acid catalyzed asymmetric ring openings of meso-epoxides, we show that noncovalent interactions of the substrates with the 3,3'-aryl groups of the catalyst play only an indirect role in stereoselectivity. Instead, the stereoselectivity of these reactions are driven by the electrostatic stabilization of a fleeting partial positive charge in the SN2-like transition state by the chiral electrostatic environment of the phosphoric acid catalyst. Next, we describe our studies of bipyridine N-oxide and N,N'-dioxide catalyzed alkylation reactions. Based on several examples, we demonstrate that there are many potential arrangements of ligands around a hexacoordinate silicon in the stereocontrolling TS, and one must consider all of these in order to identify the lowest-lying TS structures. We also present a model in which electrostatic interactions between a formyl CH group and a chlorine in these TSs underlie the enantioselectivity of these reactions. Finally, we discuss our efforts to develop computational tools for the screening of potential organocatalyst designs, starting in the context of bipyridine N,N'-dioxide catalyzed alkylation reactions. Our new computational tool kit (AARON) has been used to design highly effective catalysts for the asymmetric propargylation of benzaldehyde, and is currently being used to screen catalysts for other reactions. We conclude with our views on the potential roles of computational chemistry in the future of organocatalyst design.
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Affiliation(s)
- Steven E. Wheeler
- Department of Chemistry, Texas A&M University, College Station, Texas, 77842 United States
| | - Trevor J. Seguin
- Department of Chemistry, Texas A&M University, College Station, Texas, 77842 United States
| | - Yanfei Guan
- Department of Chemistry, Texas A&M University, College Station, Texas, 77842 United States
| | - Analise C. Doney
- Department of Chemistry, Texas A&M University, College Station, Texas, 77842 United States
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14
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Sperger T, Sanhueza IA, Kalvet I, Schoenebeck F. Computational Studies of Synthetically Relevant Homogeneous Organometallic Catalysis Involving Ni, Pd, Ir, and Rh: An Overview of Commonly Employed DFT Methods and Mechanistic Insights. Chem Rev 2015. [PMID: 26207572 DOI: 10.1021/acs.chemrev.5b00163] [Citation(s) in RCA: 415] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Theresa Sperger
- Institute of Organic Chemistry, RWTH Aachen University , Landoltweg 1, 52074 Aachen, Germany
| | - Italo A Sanhueza
- Institute of Organic Chemistry, RWTH Aachen University , Landoltweg 1, 52074 Aachen, Germany.,Laboratory of Organic Chemistry, ETH Zürich , Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Indrek Kalvet
- Institute of Organic Chemistry, RWTH Aachen University , Landoltweg 1, 52074 Aachen, Germany
| | - Franziska Schoenebeck
- Institute of Organic Chemistry, RWTH Aachen University , Landoltweg 1, 52074 Aachen, Germany
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15
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Rooks BJ, Haas MR, Sepúlveda D, Lu T, Wheeler SE. Prospects for the Computational Design of Bipyridine N,N′-Dioxide Catalysts for Asymmetric Propargylation Reactions. ACS Catal 2014. [DOI: 10.1021/cs5012553] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Benjamin J. Rooks
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Madison R. Haas
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Diana Sepúlveda
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Tongxiang Lu
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Steven E. Wheeler
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
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16
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Sreenithya A, Sunoj RB. Mechanistic insights on iodine(III) promoted metal-free dual C-H activation involved in the formation of a spirocyclic bis-oxindole. Org Lett 2014; 16:6224-7. [PMID: 25420189 DOI: 10.1021/ol503161g] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The mechanism of a metal-free, phenyliodine(III) bis(trifluoroacetate) promoted, dual aryl C-H activation of an anilide to a spirocyclic bis-oxindole is examined using density functional theory (M06-2X). The most preferred pathway proceeds through the involvement of a novel iodonium ion intermediate and a pivotal trifluoroacetate counterion. The two sequential aryl C-H activations, assisted by trifluoroacetate as well as the superior leaving group ability of PhI, facilitate the formation of spirocyclic bis-oxindole.
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Affiliation(s)
- A Sreenithya
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Raghavan B Sunoj
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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17
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Xue XS, Yang C, Li X, Cheng JP. Computational Study on the pKa Shifts in Proline Induced by Hydrogen-Bond-Donating Cocatalysts. J Org Chem 2014; 79:1166-73. [DOI: 10.1021/jo402605n] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Xiao-Song Xue
- State Key Laboratory of Elemento-Organic
Chemistry, Collaborative Innovation Center of Chemical Science and
Engineering, Department of Chemistry, Nankai University, Tianjin 300071, China
| | - Chen Yang
- State Key Laboratory of Elemento-Organic
Chemistry, Collaborative Innovation Center of Chemical Science and
Engineering, Department of Chemistry, Nankai University, Tianjin 300071, China
| | - Xin Li
- State Key Laboratory of Elemento-Organic
Chemistry, Collaborative Innovation Center of Chemical Science and
Engineering, Department of Chemistry, Nankai University, Tianjin 300071, China
| | - Jin-Pei Cheng
- State Key Laboratory of Elemento-Organic
Chemistry, Collaborative Innovation Center of Chemical Science and
Engineering, Department of Chemistry, Nankai University, Tianjin 300071, China
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18
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Xue XS, Li X, Yu A, Yang C, Song C, Cheng JP. Mechanism and Selectivity of Bioinspired Cinchona Alkaloid Derivatives Catalyzed Asymmetric Olefin Isomerization: A Computational Study. J Am Chem Soc 2013; 135:7462-73. [DOI: 10.1021/ja309133z] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Xiao-Song Xue
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xin Li
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ao Yu
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chen Yang
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chan Song
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jin-Pei Cheng
- State
Key Laboratory of Elemento-Organic Chemistry, §Computational Center of Molecular
Science, and ‡Central Laboratory, College of Chemistry, Nankai University, Tianjin 300071, China
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19
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Sharma AK, Sunoj RB. Refined Transition-State Models for Proline-Catalyzed Asymmetric Michael Reactions under Basic and Base-Free Conditions. J Org Chem 2012. [DOI: 10.1021/jo3023654] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Akhilesh K. Sharma
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Raghavan B. Sunoj
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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20
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Lu T, Zhu R, An Y, Wheeler SE. Origin of Enantioselectivity in the Propargylation of Aromatic Aldehydes Catalyzed by Helical N-Oxides. J Am Chem Soc 2012; 134:3095-102. [DOI: 10.1021/ja209241n] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Tongxiang Lu
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Rongxiu Zhu
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
- School of
Chemistry and Chemical
Engineering, Shandong University, Jinan,
People’s Republic of China
| | - Yi An
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Steven E. Wheeler
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
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