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Simonetti M, Kuniyil R, Macgregor SA, Larrosa I. Benzoate Cyclometalation Enables Oxidative Addition of Haloarenes at a Ru(II) Center. J Am Chem Soc 2018; 140:11836-11847. [PMID: 30134657 PMCID: PMC6192667 DOI: 10.1021/jacs.8b08150] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
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The
first Ru(II)-catalyzed arylation of substrates without a directing
group was recently developed. Remarkably, this process only worked
in the presence of a benzoate additive, found to be crucial for the
oxidative addition step at Ru(II). However, the exact mode of action
of the benzoate was unknown. Herein, we disclose a mechanistic study
that elucidates the key role of the benzoate salt in the C–H
arylation of fluoroarenes with aryl halides. Through a combination
of rationally designed stoichiometric experiments and DFT studies,
we demonstrate that the aryl–Ru(II) species arising from initial
C–H activation of the fluoroarene undergoes cyclometalation
with the benzoate to generate an anionic Ru(II) intermediate. The
enhanced lability of this intermediate, coupled with the electron-rich
anionic Ru(II) metal center renders the oxidative addition of the
aryl halide accessible. The role of an additional (NMe4)OC(CF3)3 additive in facilitating the overall
arylation process is also shown to be linked to a shift in the C–H
pre-equilibrium associated with benzoate cyclometalation.
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Affiliation(s)
- Marco Simonetti
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , U.K
| | - Rositha Kuniyil
- Institute of Chemical Sciences , Heriot-Watt University , Edinburgh EH14 4AS , U.K
| | - Stuart A Macgregor
- Institute of Chemical Sciences , Heriot-Watt University , Edinburgh EH14 4AS , U.K
| | - Igor Larrosa
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , U.K
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2
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Sumita A, Otani Y, Ohwada T. Electrophilic activation of aminocarboxylic acid by phosphate ester promotes Friedel-Crafts acylation by overcoming charge-charge repulsion. Org Biomol Chem 2017; 15:9398-9407. [PMID: 29094123 DOI: 10.1039/c7ob02158e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Friedel-Crafts acylation of aromatic compounds with aminocarboxylic acids proceeds efficiently in the presence of a tailored phosphate ester and a strong Brønsted acid, despite the strong charge-charge repulsion associated with acylium ion formation. Here, we investigate the mechanism of this electrophilic aromatic acylation reaction, focusing on how the aminocarboxylic acid is activated by the phosphate ester and how the charge-charge repulsion is overcome. In the first step of the reaction, an acyl phosphate is generated from the aminocarboxylic acid through the intervention of the phosphate ester, which possesses three methyl salicylate ester linkages. The o-methyl salicylates enhance the reactivity of the phosphate ester via a protonation-induced conformational change, thereby overwhelming the charge-charge repulsion associated with the acylium ion formation. Weakening of the resonance interaction in the C(O)-O(P) bond by the lone-pair electrons of the ether oxygen atom of the carboxylic acid functionality contributes to the rapid formation of the acylium ion. Thus, our results show that the formation of aromatic ketones from various carboxylic acids proceeds because the strong leaving ability of the acyl phosphate overwhelms the charge-charge repulsion associated with the formation of the acylium ion. This information will be helpful to improve the design of tailored phosphate reagents.
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Affiliation(s)
- Akinari Sumita
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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3
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Brown RS. Metal Ion-Promoted Leaving Group Assistance in the Light Alcohols. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2015. [DOI: 10.1016/bs.apoc.2015.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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4
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Sumita A, Kurouchi H, Otani Y, Ohwada T. Acid-Promoted Chemoselective Introduction of Amide Functionality onto Aromatic Compounds Mediated by an Isocyanate Cation Generated from Carbamate. Chem Asian J 2014; 9:2995-3004. [DOI: 10.1002/asia.201402625] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Indexed: 01/01/2023]
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5
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Song Y, Zan J, Yan H, Lu ZL, Wang R. Steric effects on the catalytic activities of zinc(II) complexes containing [12]aneN3 ligating units in the cleavage of the RNA and DNA model phosphates. Org Biomol Chem 2013; 10:7714-20. [PMID: 22699360 DOI: 10.1039/c2ob25624j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A series of N-methylated mono- and di-[12]aneN(3) ligands () have been synthesized and characterized. The steric effects on the catalytic activities of their mononuclear and dinuclear zinc(ii) complexes in the cleavage of a RNA model 2-hydroxypropyl 4-nitrophenyl phosphate (HPNPP, ) and a DNA model methyl 4-nitrophenyl phosphates (MPNPP, 4) in methanol have been investigated at 25 °C. In the cleavage of phosphate catalyzed by the mononuclear complexes, derived from the N-methylation in the [12]aneN(3) backbone, the plots of k(obs)versus [Zn(II)] changed from an upward curvature to linearity with increasing level of methylation, indicating that N-methylations led to a reduction of dinuclear association that was responsible for the synergetic effect. Compared to the activities of the complex with non-methylated di-[12]aneN(3) ligand, those of the dinuclear zinc(ii) complex (Zn(2)-8), which has the two N-methyl groups, were reduced by two orders of magnitude as measured by the second-order rate constants and synergetic effect in the cleavage of both model compounds. For reactions catalyzed by the fully N-methylated dinuclear complex (Zn(2)-9), no synergetic effect was observed. Nevertheless, complex Zn(2)-8 still showed the remarkable catalytic efficiency, with rate accelerations of 10(9-10)-fold in the cleavage of each of the two phosphates relative to the background reactions, and the synergetic effects of up to 561 folds. pH jump experiments confirmed that the rate-limiting step in the cleavage of by Zn(2)-8 involved the binding process, while that in the reaction with 4 was the chemical cleavage of the P-O bond. Steric effects in the cleavage reactions were analyzed in detail and were compared with the electronic effect caused by oxy anion bridging group in the di-[12]aneN(3) ligand and also with the hydrophobic effect observed in other systems. The work has further confirmed that the combination of the cooperativity between two metal ions and a medium effect could result in excellent catalytic activities for the cleavage of phosphate diesters.
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Affiliation(s)
- Yang Song
- College of Chemistry, Beijing Normal University, Xinjiekouwai Street 19, Beijing, 100875, China
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6
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A. R. Raycroft M, Liu CT, Brown RS. Comparison of Cu(II)-Promoted Leaving Group Stabilization of the Cleavage of a Homologous Set of Phosphate Mono-, Di-, and Triesters in Water, Methanol, and Ethanol. Inorg Chem 2012; 51:3846-54. [DOI: 10.1021/ic300059e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Mark A. R. Raycroft
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - C. Tony Liu
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - R. Stan Brown
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
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7
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Edwards DR, Maxwell CI, Harkness RW, Neverov AA, Mosey NJ, Stan Brown R. Experimental and computational determination of Brønsted coefficients for equilibrium transfer of the O
,O
-dimethyl phosphorothioyl group between oxyanion nucleophiles. J PHYS ORG CHEM 2011. [DOI: 10.1002/poc.1903] [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]
Affiliation(s)
- David R. Edwards
- Department of Chemistry; Queen's University; Kingston Ontario K7L 3N6 Canada
| | | | - Robert W. Harkness
- Department of Chemistry; Queen's University; Kingston Ontario K7L 3N6 Canada
| | - Alexei A. Neverov
- Department of Chemistry; Queen's University; Kingston Ontario K7L 3N6 Canada
| | - Nicholas J. Mosey
- Department of Chemistry; Queen's University; Kingston Ontario K7L 3N6 Canada
| | - R. Stan Brown
- Department of Chemistry; Queen's University; Kingston Ontario K7L 3N6 Canada
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8
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Liu CT, Neverov AA, Brown RS. Palladacycle-Promoted Solvolytic Cleavage of O,O-Dimethyl O-Aryl Phosphorothioates. Converting a Phosphorane-Like Transition State to an Observable Intermediate. Inorg Chem 2011; 50:7852-62. [DOI: 10.1021/ic201062h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- C. Tony Liu
- Department of Chemistry, Queen’s University, Kingston, Ontario K7L 3N6, Canada
| | - Alexei A. Neverov
- Department of Chemistry, Queen’s University, Kingston, Ontario K7L 3N6, Canada
| | - R. Stan Brown
- Department of Chemistry, Queen’s University, Kingston, Ontario K7L 3N6, Canada
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9
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Jensen KH, Webb JD, Sigman MS. Advancing the mechanistic understanding of an enantioselective palladium-catalyzed alkene difunctionalization reaction. J Am Chem Soc 2010; 132:17471-82. [PMID: 21082845 PMCID: PMC3066298 DOI: 10.1021/ja108106h] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mechanism of an enantioselective palladium-catalyzed alkene difunctionalization reaction has been investigated. Kinetic analysis provides evidence of turnover-limiting attack of a proposed quinone methide intermediate with MeOH and suggests that copper is involved in productive product formation, not just catalyst turnover. Through examination of substrate electronic effects, a Jaffé relationship was observed correlating rate to electronic perturbation at two positions of the substrate. Ligand effects were evaluated to provide evidence of rapid ligand exchange between palladium and copper as well as a correlation between ligand electronic nature and enantioselectivity.
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Affiliation(s)
- Katrina H. Jensen
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112
| | - Jonathan D. Webb
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6
| | - Matthew S. Sigman
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112
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Seo JA, Kim SI, Hong YJ, Um IH. Effect of Alkali Metal Ions on Nucleophilic Substitution Reactions of 4-Nitrophenyl X-Substituted Benzoates with Alkali Metal Ethoxides in Anhydrous Ethanol. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.02.303] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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11
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Liu CT, Neverov AA, Maxwell CI, Brown RS. Demonstration of Prominent Cu(II)-Promoted Leaving Group Stabilization of the Cleavage of a Homologous Set of Phosphate Mono-, Di-, and Triesters in Methanol. J Am Chem Soc 2010; 132:3561-73. [DOI: 10.1021/ja910111q] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- C. Tony Liu
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - Alexei A. Neverov
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | | | - R. Stan Brown
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
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12
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Greig IR. The analysis of enzymic free energy relationships using kinetic and computational models. Chem Soc Rev 2010; 39:2272-301. [DOI: 10.1039/b902741f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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13
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Edwards DR, Liu CT, Garrett GE, Neverov AA, Brown RS. Leaving Group Assistance in the La3+-Catalyzed Cleavage of Dimethyl (o-Methoxycarbonyl)aryl Phosphate Triesters in Methanol. J Am Chem Soc 2009; 131:13738-48. [DOI: 10.1021/ja904659e] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- David R. Edwards
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - C. Tony Liu
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - Graham E. Garrett
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - Alexei A. Neverov
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
| | - R. Stan Brown
- Department of Chemistry, Queen’s University, Kingston, Ontario, Canada K7L 3N6
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14
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Dinuclear Zn(II) catalysts as biomimics of RNA and DNA phosphoryl transfer enzymes: changing the medium from water to alcohol provides enzyme-like rate enhancements. J PHYS ORG CHEM 2009. [DOI: 10.1002/poc.1584] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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