1
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Meng B, Liu L, Shen X, Fan W, Li S. Pyridine N-Oxide-Promoted Cobalt-Catalyzed Dioxygen-Mediated Methane Oxidation. J Org Chem 2023. [PMID: 37486801 DOI: 10.1021/acs.joc.3c00770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
The partial oxidation of methane with O2 is significant due to its potential of providing abundant chemical feedstock. Only a few examples realized this type of reaction in homogeneous solvent systems, most of which are in low efficiency. Herein, we present a pyridine N-oxide-promoted cobalt-catalyzed O2-mediated methane oxidation to produce methylene bis(trifluoroacetate) with productivity over 500 molester molmetal-1 h-1.
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Affiliation(s)
- Bingyin Meng
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
| | - Luyao Liu
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
| | - Xiaotong Shen
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
| | - Wu Fan
- Key Laboratory of Tobacco Flavor Basic Research, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China
| | - Suhua Li
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
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2
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Chang L, Wang S, An Q, Liu L, Wang H, Li Y, Feng K, Zuo Z. Resurgence and advancement of photochemical hydrogen atom transfer processes in selective alkane functionalizations. Chem Sci 2023; 14:6841-6859. [PMID: 37389263 PMCID: PMC10306100 DOI: 10.1039/d3sc01118f] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 05/11/2023] [Indexed: 07/01/2023] Open
Abstract
The selective functionalization of alkanes has long been recognized as a prominent challenge and an arduous task in organic synthesis. Hydrogen atom transfer (HAT) processes enable the direct generation of reactive alkyl radicals from feedstock alkanes and have been successfully employed in industrial applications such as the methane chlorination process, etc. Nevertheless, challenges in the regulation of radical generation and reaction pathways have created substantial obstacles in the development of diversified alkane functionalizations. In recent years, the application of photoredox catalysis has provided exciting opportunities for alkane C-H functionalization under extremely mild conditions to trigger HAT processes and achieve radical-mediated functionalizations in a more selective manner. Considerable efforts have been devoted to building more efficient and cost-effective photocatalytic systems for sustainable transformations. In this perspective, we highlight the recent development of photocatalytic systems and provide our views on current challenges and future opportunities in this field.
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Affiliation(s)
- Liang Chang
- School of Pharmacy, Nanjing University of Chinese Medicine Nanjing 210023 China
| | - Shun Wang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
| | - Qing An
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
| | - Linxuan Liu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
| | - Hexiang Wang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
| | - Yubo Li
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
| | - Kaixuan Feng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
| | - Zhiwei Zuo
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences Shanghai 200032 China
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3
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Study of Cyclohexane and Methylcyclohexane Functionalization Promoted by Manganese(III) Compounds. INORGANICS 2023. [DOI: 10.3390/inorganics11030105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023] Open
Abstract
Alkane functionalization using safe and low-energy processes is of great interest to industry and academia. Aiming to contribute to the process of saturated hydrocarbon functionalization, we have studied a set of three manganese(III) complexes as catalysts for promoting the oxidation of saturated hydrocarbons (cyclohexane and methylcyclohexane) in the presence of hydrogen peroxide or trichloroisocyanuric acid (TCCA). The mononuclear manganese(III) compounds were prepared using the ligands H2LMet4 (6,6’-((1,4-diazepane-1,4-diyl)bis(methylene))bis(2,4-dimethylphenol), H2salen (2,2’-((1E,1’E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))diphenol) and H2salan (2,2’-((ethane-1,2-diylbis(azanediyl))bis(methylene))diphenol). The catalytic processes were carried out in acetonitrile at 25 and 50 °C for 24 h. The increase in the temperature was important to get a better conversion. The compounds did not promote cyclohexane oxidation in the presence of H2O2. However, they were active in the presence of TCCA, employing a ratio of 1000:333:1 equivalents of the substrate:TCCA:catalyst. The best catalytic activity was shown by the compound [Mn(salen)Cl], reaching conversions of 14.5 ± 0.3% (25 °C) and 26.3 ± 1.1% (50 °C) (yield for chlorocyclohexane) and up to 12.1 ± 0.5% (25 °C) and 29.8 ± 2.2% (50 °C) (total yield for the mixture of the products 1-chloro-4-methylcyclohexane, 3-methylcyclohexene and 1-methylcyclohexene). The interaction of the catalysts with TCCA was studied using electron paramagnetic resonance (EPR), suggesting that the catalysts [Mn(LMet4)Cl] and [Mn(salan)Cl] act via a different mechanism from that observed for [Mn(salen)Cl].
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4
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Liu L, Fan W, Li S. NaCl-Promoted Cobalt-Catalyzed Dioxygen-Mediated Methane Oxidation to Methylene Bis(trifluoroacetate) with a Dramatic Salt Effect. ACS Catal 2023. [DOI: 10.1021/acscatal.3c00162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Luyao Liu
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
| | - Wu Fan
- Key Laboratory of Tobacco Flavor Basic Research, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China
| | - Suhua Li
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
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5
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Coutard N, Musgrave CB, Moon J, Liebov NS, Nielsen RM, Goldberg JM, Li M, Jia X, Lee S, Dickie DA, Schinski WL, Wu Z, Groves JT, Goddard WA, Gunnoe TB. Manganese Catalyzed Partial Oxidation of Light Alkanes. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Nathan Coutard
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Charles B. Musgrave
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, United States
| | - Jisue Moon
- Chemical Science Division, Oak Ridge National Lab, Oak Ridge, Tennessee 37831, United States
| | - Nichole S. Liebov
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Robert M. Nielsen
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, United States
| | - Jonathan M. Goldberg
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Meijun Li
- Chemical Science Division, Oak Ridge National Lab, Oak Ridge, Tennessee 37831, United States
| | - Xiaofan Jia
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Sungsik Lee
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Diane A. Dickie
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | | | - Zili Wu
- Chemical Science Division, Oak Ridge National Lab, Oak Ridge, Tennessee 37831, United States
| | - John T. Groves
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - William A. Goddard
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, United States
| | - T. Brent Gunnoe
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
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6
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Coutard N, Goldberg JM, Valle HU, Cao Y, Jia X, Jeffrey PD, Gunnoe TB, Groves JT. Aerobic Partial Oxidation of Alkanes Using Photodriven Iron Catalysis. Inorg Chem 2021; 61:759-766. [PMID: 34962799 DOI: 10.1021/acs.inorgchem.1c03086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photodriven oxidations of alkanes in trifluoroacetic acid using commercial and synthesized Fe(III) sources as catalyst precursors and dioxygen (O2) as the terminal oxidant are reported. The reactions produce alkyl esters and occur at ambient temperature in the presence of air, and catalytic turnover is observed for the oxidation of methane in a pure O2 atmosphere. Under optimized conditions, approximately 17% conversion of methane to methyl trifluoroacetate at more than 50% selectivity is observed. It is demonstrated that methyl trifluoroacetate is stable under catalytic conditions, and thus overoxidized products are not formed through secondary oxidation of methyl trifluoroacetate.
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Affiliation(s)
- Nathan Coutard
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Jonathan M Goldberg
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Henry U Valle
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Yuan Cao
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Xiaofan Jia
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Philip D Jeffrey
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - T Brent Gunnoe
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - John T Groves
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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7
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Hirscher NA, Ohri N, Yang Q, Zhou J, Anna JM, Schelter EJ, Goldberg KI. A Metal-Free, Photocatalytic Method for Aerobic Alkane Iodination. J Am Chem Soc 2021; 143:19262-19267. [PMID: 34779622 DOI: 10.1021/jacs.1c08499] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Halogenation is an important alkane functionalization strategy, but O2 is widely considered the most desirable terminal oxidant. Here, the aerobic iodination of alkanes, including methane, was performed using catalytic [nBu4N]Cl and light irradiation (390 nm). Up to 10 turnovers of CH3I were obtained from CH4 and air, using a stop-flow microtubing system. Mechanistic studies using cyclohexane as the substrate revealed important details about the iodination reaction. Iodine (I2) serves multiple roles in the catalysis: (1) as the alkyl radical trap, (2) as a precursor for the light absorber, and (3) as a mediator of aerobic oxidation. The alkane activation is attributed to Cl• derived from photofragmentation of the electron donor-acceptor complex of I2 and Cl-. The kinetic profile of cyclohexane iodination showed that aerobic oxidation of I3- to produce I2 in CH3CN is turnover-limiting.
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Affiliation(s)
- Nathanael A Hirscher
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Nidhi Ohri
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Qiaomu Yang
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Jiawang Zhou
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Jessica M Anna
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Eric J Schelter
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Karen I Goldberg
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
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8
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Chen SS, Koppaka A, Periana RA, Ess DH. Theory and Experiment Demonstrate that Sb(V)-Promoted Methane C-H Activation and Functionalization Outcompete Superacid Protonolysis in Sulfuric Acid. J Am Chem Soc 2021; 143:18242-18250. [PMID: 34665603 DOI: 10.1021/jacs.1c08170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Sb(V) in strong Brønsted acid solvents is traditionally assumed to react with light alkanes through superacid protonolysis, which results in carbocation intermediates, H2, and carbon oligomerization. In contrast to this general assumption, our density functional theory (DFT) calculations revealed an accessible barrier for C-H activation between methane and Sb(V) in sulfuric acid that could potentially outcompete superacid protonolysis. This prompted us to experimentally examine this reaction in sulfuric acid with oleum, which has never been reported because of presumed superacid reactivity. Reaction of methane at 180 °C for 3 h resulted in very high yields of methyl bisulfate without significant overoxidation. Our DFT calculations show that a C-H activation and Sb-Me bond functionalization mechanism to give methyl bisulfate outcompetes methane protonolysis and many other possible reaction mechanisms, such as electron transfer, proton-coupled electron transfer, and hydride abstraction. Our DFT calculations also explain experimental hydrogen-deuterium exchange studies and the absence of methane carbo-functionalization/oligomerization products. Overall, this work demonstrates that in very strong Brønsted acid solvent, Sb(V) can induce innersphere reaction mechanisms akin to transition metals and outcompete superacid reactivity.
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Affiliation(s)
- Shu-Sen Chen
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Anjaneyulu Koppaka
- The Scripps Energy and Materials Center, Department of Chemistry, The Scripps Research Institute, Jupiter, Florida 33458, United States
| | - Roy A Periana
- The Scripps Energy and Materials Center, Department of Chemistry, The Scripps Research Institute, Jupiter, Florida 33458, 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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Huang T, Xu Z, Yan P, Liu X, Fan H, Zhang ZC. Direct Partial Oxidation of Methane Catalyzed by an In Situ Generated Active Au(III) Complex at Low Temperature in Ionic Liquids. Organometallics 2021. [DOI: 10.1021/acs.organomet.0c00714] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tingyu Huang
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 10049, China
| | - Zhanwei Xu
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian 116023, China
| | - Peifang Yan
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian 116023, China
| | - Xiumei Liu
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian 116023, China
| | - Hongjun Fan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian 116023, China
| | - Z. Conrad Zhang
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian 116023, China
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10
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Liu L, Fan W, Chen W, Chen X, Li S. KF-Promoted copper-catalyzed highly efficient and selective oxidation of methane and other alkanes with a dramatic additive effect. Catal Sci Technol 2021. [DOI: 10.1039/d1cy00474c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Selective oxidation of methane is traditionally challenging. Now using KF could dramatic improve the efficiency of copper catalyzed methane oxidation with K2S2O8 as oxidant. The role of KF is conjectured to promote [SO4˙]− to escape the solvent cage.
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Affiliation(s)
- Luyao Liu
- School of Chemistry
- Sun Yat-Sen University
- Guangzhou 510275
- China
| | - Wu Fan
- Key Laboratory of Tobacco Flavor Basic Research
- Zhengzhou Tobacco Research Institute of CNTC
- Zhengzhou 450001
- China
| | - Wei Chen
- Department of Colorectal Surgery & Guangdong Provincial Key laboratory of Colorectal and Pelvic Floor Disease & Guangdong Research Institute of Gastroenterology
- The Sixth Affiliated Hospital of Sun Yat-Sen University
- Guangzhou 510655
- China
| | - Xiaoyan Chen
- School of Chemistry
- Sun Yat-Sen University
- Guangzhou 510275
- China
| | - Suhua Li
- School of Chemistry
- Sun Yat-Sen University
- Guangzhou 510275
- China
- Key Lab of Functional Molecular Engineering of Guangdong Province
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11
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Kim RS, Nazemi A, Cundari TR, Surendranath Y. A PdIII Sulfate Dimer Initiates Rapid Methane Monofunctionalization by H Atom Abstraction. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03844] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R. Soyoung Kim
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Azadeh Nazemi
- Department of Chemistry, CASCaM, University of North Texas, Denton, Texas 76203, United States
| | - Thomas R. Cundari
- Department of Chemistry, CASCaM, University of North Texas, Denton, Texas 76203, United States
| | - Yogesh Surendranath
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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12
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Maksimović JP, Tošović J, Pagnacco MC. Insight into the Origin of Pyrocatechol Inhibition on Oscillating Bray-Liebhafsky Reaction: Combined Experimental and Theoretical Study. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2020. [DOI: 10.1246/bcsj.20190296] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Jelena P. Maksimović
- Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia
| | - Jelena Tošović
- Faculty of Science, University of Kragujevac, Kragujevac, Serbia
| | - Maja C. Pagnacco
- University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Center of Catalysis and Chemical Engineering, Njegoseva 12, Belgrade, Serbia
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13
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Zagrean-Tuza C, Dorneanu S, Mot AC. The strange case of polyphenols inhibiting the Briggs-Rauscher reaction: pH-modulated reactivity of the superoxide radical. Free Radic Biol Med 2020; 146:189-197. [PMID: 31705959 DOI: 10.1016/j.freeradbiomed.2019.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/22/2019] [Accepted: 11/04/2019] [Indexed: 11/25/2022]
Abstract
Superoxide radical is one of the main players when it comes to oxidative stress. Even if in itself is moderately reactive and can cause the degradation of very few biologically relevant macromolecules, it can dismutate to hydrogen peroxide followed by a possible conversion to hydroxyl radical. In order to protect the internal environment against reactive oxygen species, plants have evolved a line of defence made from secondary metabolites with versatile redox properties, such as flavonoids and phenolic acids. Their characteristics are highly modulated by pH, as they turn into prooxidant compounds as it increases. Reported here are the behaviour and clear patterns in reactivity towards superoxide anion radical of four classes of plant phenolics as a pH function. The reactivity towards superoxide radical in acidic conditions has been studied by use of oscillating Briggs-Rauscher reaction with a new spectroelectrochemical experimental setup, by recording the absorbance in high quality for the first time. Some mechanistic intricacies have also been explored with regard to this method. Reactivity modulation at neutral and slightly basic pH has been assayed by superoxide radical scavenging ability using nitroblue tetrazolium as a substrate. For stronger alkaline pHs studies, Electron Paramagnetic Resonance was exploited. Hydroxybenzoic acids tend to be the least reactive species at all tested pH values. Hydroxycinnamic acids have their activity towards superoxide radical decreased as the pH increases, whereas flavonoids act vice versa.
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Affiliation(s)
- Cezara Zagrean-Tuza
- Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
| | - Sorin Dorneanu
- Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
| | - Augustin C Mot
- Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Cluj-Napoca, Romania.
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14
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Synthesis, structure, and reactivity of tetravalent cerium complexes containing oxidizing oxyanion ligands. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2019.120902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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15
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Liebov NS, Goldberg JM, Boaz NC, Coutard N, Kalman SE, Zhuang T, Groves JT, Gunnoe TB. Selective Photo‐Oxygenation of Light Alkanes Using Iodine Oxides and Chloride. ChemCatChem 2019. [DOI: 10.1002/cctc.201901175] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Nichole S. Liebov
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
| | | | - Nicholas C. Boaz
- Department of Chemistry Princeton University Princeton NJ 08544 USA
- Department of Chemistry North Central College Naperville IL 60540 USA
| | - Nathan Coutard
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
| | - Steven E. Kalman
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
- Chemistry Program School of Natural Sciences and Mathematics Stockton University Galloway NJ 08205 USA
| | - Thompson Zhuang
- Department of Chemistry Princeton University Princeton NJ 08544 USA
| | - John T. Groves
- Department of Chemistry Princeton University Princeton NJ 08544 USA
| | - T. Brent Gunnoe
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
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16
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LaMartina KB, Kuck HK, Oglesbee LS, Al-Odaini A, Boaz NC. Selective benzylic C-H monooxygenation mediated by iodine oxides. Beilstein J Org Chem 2019; 15:602-609. [PMID: 30931001 PMCID: PMC6423598 DOI: 10.3762/bjoc.15.55] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 02/19/2019] [Indexed: 12/30/2022] Open
Abstract
A method for the selective monooxdiation of secondary benzylic C–H bonds is described using an N-oxyl catalyst and a hypervalent iodine species as a terminal oxidant. Combinations of ammonium iodate and catalytic N-hydroxyphthalimide (NHPI) were shown to be effective in the selective oxidation of n-butylbenzene directly to 1-phenylbutyl acetate in high yield (86%). This method shows moderate substrate tolerance in the oxygenation of substrates containing secondary benzylic C–H bonds, yielding the corresponding benzylic acetates in good to moderate yield. Tertiary benzylic C–H bonds were shown to be unreactive under similar conditions, despite the weaker C–H bond. A preliminary mechanistic analysis suggests that this NHPI-iodate system is functioning by a radical-based mechanism where iodine generated in situ captures formed benzylic radicals. The benzylic iodide intermediate then solvolyzes to yield the product ester.
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Affiliation(s)
- Kelsey B LaMartina
- Department of Chemistry and Physics, North Central College, 30 N. Brainard Street, Naperville, IL 60540 USA
| | - Haley K Kuck
- Department of Chemistry and Physics, North Central College, 30 N. Brainard Street, Naperville, IL 60540 USA
| | - Linda S Oglesbee
- Department of Chemistry and Physics, North Central College, 30 N. Brainard Street, Naperville, IL 60540 USA
| | - Asma Al-Odaini
- Department of Chemistry and Physics, North Central College, 30 N. Brainard Street, Naperville, IL 60540 USA
| | - Nicholas C Boaz
- Department of Chemistry and Physics, North Central College, 30 N. Brainard Street, Naperville, IL 60540 USA.,Department of Chemistry, Frick Chemical Laboratory, Princeton University, Washington Road, Princeton, NJ 08544 USA.,Permanent address: Department of Chemistry, North Central College, 30 N. Brainard Street, Naperville, IL 60540 USA; phone: +1-630-637-5187
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17
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King CR, Rollins N, Holdaway A, Konnick MM, Periana RA, Ess DH. Electrophilic Impact of High-Oxidation State Main-Group Metal and Ligands on Alkane C–H Activation and Functionalization Reactions. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00418] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Clinton R. King
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Nick Rollins
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Ashley Holdaway
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Michael M. Konnick
- Hyconix, Inc., 4575 Weaver Parkway, Warrenville, Illinois 60555, United States
| | - Roy A. Periana
- Department of Chemistry, The Scripps Research Institute, Jupiter, Florida 33458, United States
| | - Daniel H. Ess
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
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