1
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Dale HA, Hodges GR, Lloyd-Jones GC. Kinetics and Mechanism of Azole n-π*-Catalyzed Amine Acylation. J Am Chem Soc 2023; 145:18126-18140. [PMID: 37526380 PMCID: PMC10436283 DOI: 10.1021/jacs.3c06258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Indexed: 08/02/2023]
Abstract
Azole anions are highly competent in the activation of weak acyl donors, but, unlike neutral (aprotic) Lewis bases, are not yet widely applied as acylation catalysts. Using a combination of in situ and stopped-flow 1H/19F NMR spectroscopy, kinetics, isotopic labeling, 1H DOSY, and electronic structure calculations, we have investigated azole-catalyzed aminolysis of p-fluorophenyl acetate. The global kinetics have been elucidated under four sets of conditions, and the key elementary steps underpinning catalysis deconvoluted using a range of intermediates and transition state probes. While all evidence points to an overarching mechanism involving n-π* catalysis via N-acylated azole intermediates, a diverse array of kinetic regimes emerges from this framework. Even seemingly minor changes to the solvent, auxiliary base, or azole catalyst can elicit profound changes in the temporal evolution, thermal sensitivity, and progressive inhibition of catalysis. These observations can only be rationalized by taking a holistic view of the mechanism and a set of limiting regimes for the kinetics. Overall, the analysis of 18 azole catalysts spanning nearly 10 orders of magnitude in acidity highlights the pitfall of pursuing ever more nucleophilic catalysts without regard for catalyst speciation.
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Affiliation(s)
- Harvey
J. A. Dale
- EaStChem, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K.
| | - George R. Hodges
- Jealott’s
Hill International Research Centre, Syngenta, Bracknell, Berkshire RG42 6EY, U.K.
| | - Guy C. Lloyd-Jones
- EaStChem, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K.
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2
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Neumann N, Thinius S, Abels G, Hartwig A, Koschek K, Boskamp L. Multifunctional hyperbranched prepolymers with tailored degree of methylation and methacrylation. POLYMER 2023. [DOI: 10.1016/j.polymer.2023.125886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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3
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Valentini F, Galloni P, Brancadoro D, Conte V, Sabuzi F. A Stoichiometric Solvent-Free Protocol for Acetylation Reactions. Front Chem 2022; 10:842190. [PMID: 35355791 PMCID: PMC8959667 DOI: 10.3389/fchem.2022.842190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
Considering the remarkable relevance of acetylated derivatives of phenols, alcohols, and aryl and alkyl thiols in different areas of biology, as well as in synthetic organic chemistry, a sustainable solvent-free approach to perform acetylation reactions is proposed here. Acetylation reactions are classically performed using excess of acetic anhydride (Ac2O) in solvent-free conditions or by eventually working with stoichiometric amounts of Ac2O in organic solvents; both methods require the addition of basic or acid catalysts to promote the esterification. Therefore, they usually lead to the generation of high amounts of wastes, which sensibly raise the E-factor of the process. With the aim to develop a more sustainable system, a solvent-free, stoichiometric acetylation protocol is, thus, proposed. The naturally occurring phenol, thymol, can be converted to the corresponding—biologically active—ester with good yields, in the presence of 1% of VOSO4. Interestingly, the process can be efficiently adopted to synthesize other thymyl esters, as well as to perform acetylation of alcohols and aryl and alkyl thiols. Remarkably, a further improvement has been achieved replacing Ac2O with its greener alternative, isopropenyl acetate (IPA).
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Affiliation(s)
- Francesca Valentini
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, Rome, Italy
| | - Pierluca Galloni
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, Rome, Italy
- BT-InnoVaChem Srl, Rome, Italy
| | | | - Valeria Conte
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, Rome, Italy
| | - Federica Sabuzi
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, Rome, Italy
- BT-InnoVaChem Srl, Rome, Italy
- *Correspondence: Federica Sabuzi,
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4
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Lyons DJM, Empel C, Pace DP, Dinh AH, Mai BK, Koenigs RM, Nguyen TV. Tropolonate Salts as Acyl-Transfer Catalysts under Thermal and Photochemical Conditions: Reaction Scope and Mechanistic Insights. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03702] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Demelza J. M. Lyons
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Claire Empel
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
- Institute of Organic Chemistry, RWTH Aachen, Aachen D52074, Germany
| | - Domenic P. Pace
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - An H. Dinh
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Binh Khanh Mai
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Rene M. Koenigs
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
- Institute of Organic Chemistry, RWTH Aachen, Aachen D52074, Germany
| | - Thanh Vinh Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
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5
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Tsutsumi T, Saitoh A, Kasai T, Chu M, Karanjit S, Nakayama A, Namba K. Synthesis and evaluation of 1,1,7,7-tetramethyl-9-azajulolidine (TMAJ) as a highly active derivative of N,N-dimethylaminopyridine. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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6
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Ashush N, Fallek R, Fallek A, Dobrovetsky R, Portnoy M. Base- and Catalyst-Induced Orthogonal Site Selectivities in Acylation of Amphiphilic Diols. Org Lett 2020; 22:3749-3754. [PMID: 32330055 DOI: 10.1021/acs.orglett.0c00830] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Seeking to selectively functionalize natural and synthetic amphiphiles, we explored acylation of model amphiphilic diols. The use of a nucleophilic catalyst enabled a remarkable shift of the site selectivity from the polar site, preferred in background noncatalyzed or base-promoted reactions, to the apolar site. This tendency was significantly enhanced for organocatalysts comprising an imidazole active site surrounded by long/branched tails. An explanation of these orthogonal modes of selectivity is supported by competitive experiments with monoalcohol substrates.
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Affiliation(s)
- Natali Ashush
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Reut Fallek
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Amit Fallek
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Roman Dobrovetsky
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Moshe Portnoy
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
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7
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Shaik S, Danovich D, Galbraith JM, Braïda B, Wu W, Hiberty PC. Charge‐Shift Bonding: A New and Unique Form of Bonding. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201910085] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Sason Shaik
- Institute of Chemistry The Hebrew University of Jerusalem 9190401 Jerusalem Israel
| | - David Danovich
- Institute of Chemistry The Hebrew University of Jerusalem 9190401 Jerusalem Israel
| | - John Morrison Galbraith
- Department of Chemistry Biochemistry and Physics, Marist College 3399 North Road Poughkeepsie NY 12601 USA
| | - Benoît Braïda
- Laboratoire de Chimie Theorique Sorbonne Universite, UMR7616 CNRS Paris 75252 France
| | - Wei Wu
- State Key Laboratory of Physical Chemistry of Solid Surfaces Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry Xiamen University Xiamen Fujian 361005 China
| | - Philippe C. Hiberty
- Laboratoire de Chimie Physique, CNRS UMR8000, Bat. 349 Université de Paris-Sud 91405 Orsay Cédex France
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8
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Shaik S, Danovich D, Galbraith JM, Braïda B, Wu W, Hiberty PC. Charge-Shift Bonding: A New and Unique Form of Bonding. Angew Chem Int Ed Engl 2019; 59:984-1001. [PMID: 31476104 DOI: 10.1002/anie.201910085] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Indexed: 12/14/2022]
Abstract
Charge-shift bonds (CSBs) constitute a new class of bonds different than covalent/polar-covalent and ionic bonds. Bonding in CSBs does not arise from either the covalent or the ionic structures of the bond, but rather from the resonance interaction between the structures. This Essay describes the reasons why the CSB family was overlooked by valence-bond pioneers and then demonstrates that the unique status of CSBs is not theory-dependent. Thus, valence bond (VB), molecular orbital (MO), and energy decomposition analysis (EDA), as well as a variety of electron density theories all show the distinction of CSBs vis-à-vis covalent and ionic bonds. Furthermore, the covalent-ionic resonance energy can be quantified from experiment, and hence has the same essential status as resonance energies of organic molecules, e.g., benzene. The Essay ends by arguing that CSBs are a distinct family of bonding, with a potential to bring about a Renaissance in the mental map of the chemical bond, and to contribute to productive chemical diversity.
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Affiliation(s)
- Sason Shaik
- Institute of Chemistry, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - David Danovich
- Institute of Chemistry, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - John Morrison Galbraith
- Department of Chemistry, Biochemistry and Physics, Marist College, 3399 North Road, Poughkeepsie, NY, 12601, USA
| | - Benoît Braïda
- Laboratoire de Chimie Theorique, Sorbonne Universite, UMR7616 CNRS, Paris, 75252, France
| | - Wei Wu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, Xiamen University, Xiamen, Fujian, 361005, China
| | - Philippe C Hiberty
- Laboratoire de Chimie Physique, CNRS UMR8000, Bat. 349, Université de Paris-Sud, 91405, Orsay Cédex, France
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9
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De Vylder A, Lauwaert J, Sabbe MK, Reyniers MF, De Clercq J, Van Der Voort P, Thybaut JW. Rational design of nucleophilic amine sites via computational probing of steric and electronic effects. Catal Today 2019. [DOI: 10.1016/j.cattod.2019.01.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Maji R, Ugale H, Wheeler SE. Understanding the Reactivity and Selectivity of Fluxional Chiral DMAP-Catalyzed Kinetic Resolutions of Axially Chiral Biaryls. Chemistry 2019; 25:4452-4459. [PMID: 30657217 DOI: 10.1002/chem.201806068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/17/2019] [Indexed: 12/17/2022]
Abstract
Fluxional chiral DMAP-catalyzed kinetic resolutions of axially chiral biaryls were examined using density functional theory. Computational analyses lead to a revised understanding of this reaction in which the interplay of numerous non-covalent interactions control the conformation and flexibility of the active catalyst, the preferred mechanism, and the stereoselectivity. Notably, while the DMAP catalyst itself is confirmed to be highly fluxional, electrostatically driven π⋅⋅⋅π+ interactions render the active, acylated form of the catalyst highly rigid, explaining its pronounced stereoselectivity.
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Affiliation(s)
- Rajat Maji
- Department of Chemistry, Texas A&M University, College Station, TX, 77842, USA
| | - Heena Ugale
- Department of Chemistry, Texas A&M University, College Station, TX, 77842, USA
| | - Steven E Wheeler
- Department of Chemistry, Texas A&M University, College Station, TX, 77842, USA.,Center for Computational Quantum Chemistry, Department of Chemistry, University of Georgia, Athens, GA, 30602, USA
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11
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Recent topics in enantioselective acyl transfer reactions with dialkylaminopyridine-based nucleophilic catalysts. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.03.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Yanagi M, Imayoshi A, Ueda Y, Furuta T, Kawabata T. Carboxylate Anions Accelerate Pyrrolidinopyridine (PPy)-Catalyzed Acylation: Catalytic Site-Selective Acylation of a Carbohydrate by in Situ Counteranion Exchange. Org Lett 2017; 19:3099-3102. [DOI: 10.1021/acs.orglett.7b01213] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Masanori Yanagi
- Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
| | - Ayumi Imayoshi
- Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
| | - Yoshihiro Ueda
- Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
| | - Takumi Furuta
- Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
| | - Takeo Kawabata
- Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
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13
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Liao RZ, Santoro S, Gotsev M, Marcelli T, Himo F. Origins of Stereoselectivity in Peptide-Catalyzed Kinetic Resolution of Alcohols. ACS Catal 2016. [DOI: 10.1021/acscatal.5b02131] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Rong-Zhen Liao
- Key
Laboratory of Material Chemistry for Energy Conversion and Storage,
Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
| | - Stefano Santoro
- Department
of Chemistry, Biology and Biotechnology, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
| | - Martin Gotsev
- Department
of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106
91 Stockholm, Sweden
| | - Tommaso Marcelli
- Department
of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106
91 Stockholm, Sweden
| | - Fahmi Himo
- Department
of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106
91 Stockholm, Sweden
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14
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Duan A, Peng L, Peng D, Gu FL. Theoretical study on the mechanism of stereoselective synthesis of oxazolidinones. J Org Chem 2013; 78:12585-92. [PMID: 24237588 DOI: 10.1021/jo4022452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxazolidinones can be synthesized through an organocatalytic cascade reaction of stable sulfur ylides and nitro-olefins. This process, sequentially catalyzed by thiourea and N,N-dimethylaminopyridine (DMAP), is theoretically studied using density functional theory by the continuum solvation model. It is shown that the rate- and stereoselectivity-determining step is the addition reaction of sulfur ylide to the nitro-olefin with two competing reaction channels. One channel is where the nitro-cyclopropane is generated first and then converted into isoxazoline N-oxide through a DMAP-catalyzed rearrangement. The other channel is the direct generation of the isoxazoline N-oxide intermediate. DMAP plays an important role in the reaction as a nucleophilic catalyst. The mechanism for the important rearrangement reaction proposed by Xiao et al. (J. Am. Chem. Soc. 2008, 130, 6946-6948) is not appropriate as the reaction energy barrier is too high; a 10-step mechanism determined by our theoretical calculations is more feasible as the energy barrier is becoming much less than that by Xiao. It is the first time that the Hofmann rearrangement involved in the cascade organocatalysis is confirmed by theoretical calculations. Our result of the stereoselectivity for the synthesis of oxazolidinones is in good agreement with the experiment.
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Affiliation(s)
- Abing Duan
- Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University , Guangzhou 510006, China
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15
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Nishino R, Furuta T, Kan K, Sato M, Yamanaka M, Sasamori T, Tokitoh N, Kawabata T. Investigation of the Carboxylate Position during the Acylation Reaction Catalyzed by Biaryl DMAP Derivatives with an Internal Carboxylate. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201300665] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Nishino R, Furuta T, Kan K, Sato M, Yamanaka M, Sasamori T, Tokitoh N, Kawabata T. Investigation of the Carboxylate Position during the Acylation Reaction Catalyzed by Biaryl DMAP Derivatives with an Internal Carboxylate. Angew Chem Int Ed Engl 2013; 52:6445-9. [DOI: 10.1002/anie.201300665] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/18/2013] [Indexed: 11/05/2022]
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17
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Ueda Y, Mishiro K, Yoshida K, Furuta T, Kawabata T. Regioselective diversification of a cardiac glycoside, lanatoside C, by organocatalysis. J Org Chem 2012; 77:7850-7. [PMID: 22870937 DOI: 10.1021/jo301007x] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Acylation of lanatoside C in the presence of organocatalyst 5 gave the C(4'''')-O-acylate in up to 90% regioselectivity (catalyst-controlled regioselectivity). Various functionalized acyl groups can be introduced at the C(4'''')-OH by a mixed anhydride method in the presence of 5 or the related organocatalyst. On the other hand, DMAP-catalyzed acylation of lanatoside C gave the C(3'''')-O-acylate in up to 97% regioselectivity (substrate-controlled regioselectivity). Thus, diverse regioselective introduction of acyl groups among eight free hydroxy groups of lanatoside C was achieved.
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Affiliation(s)
- Yoshihiro Ueda
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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18
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Lindner C, Tandon R, Maryasin B, Larionov E, Zipse H. Cation affinity numbers of Lewis bases. Beilstein J Org Chem 2012; 8:1406-42. [PMID: 23019478 PMCID: PMC3458768 DOI: 10.3762/bjoc.8.163] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 07/27/2012] [Indexed: 11/23/2022] Open
Abstract
Using selected theoretical methods the affinity of a large range of Lewis bases towards model cations has been quantified. The range of model cations includes the methyl cation as the smallest carbon-centered electrophile, the benzhydryl and trityl cations as models for electrophilic substrates encountered in Lewis base-catalyzed synthetic procedures, and the acetyl cation as a substrate model for acyl-transfer reactions. Affinities towards these cationic electrophiles are complemented by data for Lewis-base addition to Michael acceptors as prototypical neutral electrophiles.
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Affiliation(s)
- Christoph Lindner
- Department of Chemistry, Ludwigs-Maximilians-Universität München, Butenandstr. 5–13, D-81377 München, Germany
| | - Raman Tandon
- Department of Chemistry, Ludwigs-Maximilians-Universität München, Butenandstr. 5–13, D-81377 München, Germany
| | - Boris Maryasin
- Department of Chemistry, Ludwigs-Maximilians-Universität München, Butenandstr. 5–13, D-81377 München, Germany
| | - Evgeny Larionov
- Department of Chemistry, Ludwigs-Maximilians-Universität München, Butenandstr. 5–13, D-81377 München, Germany
| | - Hendrik Zipse
- Department of Chemistry, Ludwigs-Maximilians-Universität München, Butenandstr. 5–13, D-81377 München, Germany
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19
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De Rycke N, Couty F, David ORP. Increasing the Reactivity of Nitrogen Catalysts. Chemistry 2011; 17:12852-71. [DOI: 10.1002/chem.201101755] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Indexed: 11/11/2022]
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