1
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Tu JL, Huang B. Titanium in photocatalytic organic transformations: current applications and future developments. Org Biomol Chem 2024; 22:6650-6664. [PMID: 39118484 DOI: 10.1039/d4ob01152j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024]
Abstract
Titanium, as an important transition metal, has garnered extensive attention in both industry and academia due to its excellent mechanical properties, corrosion resistance, and unique reactivity in organic synthesis. In the field of organic photocatalysis, titanium-based compounds such as titanium dioxide (TiO2), titanocenes (Cp2TiCl2, CpTiCl3), titanium tetrachloride (TiCl4), tetrakis(isopropoxy)titanium (Ti(OiPr)4), and chiral titanium complexes have demonstrated distinct reactivity and selectivity. This review focuses on the roles of these titanium compounds in photocatalytic organic reactions, and highlights the reaction pathways such as photo-induced single-electron transfer (SET) and ligand-to-metal charge transfer (LMCT). By systematically surveying the latest advancements in titanium-involved organic photocatalysis, this review aims to provide references for further research and technological innovation within this fast-developing field.
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Affiliation(s)
- Jia-Lin Tu
- Faculty of Arts and Sciences, Beijing Normal University, Zhuhai 519085, China.
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
| | - Binbin Huang
- Faculty of Arts and Sciences, Beijing Normal University, Zhuhai 519085, China.
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2
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Wang A, Yin YY, Rukhsana, Wang LQ, Jin JH, Shen YM. Visible-Light-Mediated Three-Component Decarboxylative Coupling Reactions to Synthesize 1,4-Diol Monoethers. J Org Chem 2023; 88:13871-13882. [PMID: 37683099 DOI: 10.1021/acs.joc.3c01483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
An efficient approach for 1,2-difunctionalization of aromatic olefins and the synthesis of functionalized 1,4-diols monoethers has been established via a photoinduced three-component reaction of an α-alkoxycarboxylic acid, an aromatic olefin, and an aldehyde. The reaction proceeds by photoinduced oxidative decarboxylation of the carboxylic acid followed by the addition of the α-alkoxyalkyl radical to the olefin, one-electron reduction of the addition radical, and the nucleophilic attack of the resulting carbanion to the aldehyde. Besides the convenient one-pot protocol of the three-component reaction, this method offers several other advantages, including good functional group tolerance for the three substrates, gentle reaction conditions, and ease of scaling up. The reaction mechanism has been investigated through free radical trapping experiment and isotope labeling experiments.
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Affiliation(s)
- Ai Wang
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P.R. China
| | - Yu-Yun Yin
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P.R. China
- Zhejiang Sci-Tech University Shengzhou Innovation Research Institute, Shengzhou 312400, P.R. China
| | - Rukhsana
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P.R. China
| | - Le-Quan Wang
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P.R. China
| | - Jia-Hui Jin
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P.R. China
| | - Yong-Miao Shen
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P.R. China
- Zhejiang Sci-Tech University Shengzhou Innovation Research Institute, Shengzhou 312400, P.R. China
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3
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Kitcatt DM, Scott KA, Rongione E, Nicolle S, Lee AL. Direct decarboxylative Giese amidations: photocatalytic vs. metal- and light-free. Chem Sci 2023; 14:9806-9813. [PMID: 37736650 PMCID: PMC10510818 DOI: 10.1039/d3sc03143h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/23/2023] [Indexed: 09/23/2023] Open
Abstract
A direct intermolecular decarboxylative Giese amidation reaction from bench stable, non-toxic and environmentally benign oxamic acids has been developed, which allows for easy access to 1,4-difunctionalised compounds which are not otherwise readily accessible. Crucially, a more general acceptor substrate scope is now possible, which renders the Giese amidation applicable to more complex substrates such as natural products and chiral building blocks. Two different photocatalytic methods (one via oxidative and the other via reductive quenching cycles) and one metal- and light-free method were developed and the flexibility provided by different conditions proved to be crucial for enabling a more general substrate scope.
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Affiliation(s)
- David M Kitcatt
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University Edinburgh EH14 4AS UK
| | - Katie A Scott
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University Edinburgh EH14 4AS UK
| | - Elena Rongione
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University Edinburgh EH14 4AS UK
| | - Simon Nicolle
- GlaxoSmithKline Gunnels Wood Rd Stevenage SG1 2NY UK
| | - Ai-Lan Lee
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University Edinburgh EH14 4AS UK
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4
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Imamura Y, Takaoka K, Komori Y, Nagatomo M, Inoue M. Total Synthesis of Taxol Enabled by Inter- and Intramolecular Radical Coupling Reactions. Angew Chem Int Ed Engl 2023; 62:e202219114. [PMID: 36646637 DOI: 10.1002/anie.202219114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/14/2023] [Accepted: 01/16/2023] [Indexed: 01/18/2023]
Abstract
Taxol is a clinically used drug for the treatment of various types of cancers. Its 6/8/6/4-membered ring (ABCD-ring) system is substituted by eight oxygen functional groups and flanked by four acyl groups, including a β-amino acid side chain. Here we report a 34-step total synthesis of this unusually oxygenated and intricately fused structure. Inter- and intramolecular radical coupling reactions connected the A- and C-ring fragments and cyclized the B-ring, respectively. Functional groups of the A- and C-rings were then efficiently decorated by employing newly developed chemo-, regio-, and stereoselective reactions. Finally, construction of the D-ring and conjugation with the β-amino acid delivered taxol. The powerful coupling reactions and functional group manipulations implemented in the present synthesis provide new valuable information for designing multistep target-oriented syntheses of diverse bioactive natural products.
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Affiliation(s)
- Yusuke Imamura
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kyohei Takaoka
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yuma Komori
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Masanori Nagatomo
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
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5
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Lopat’eva ER, Krylov IB, Segida OO, Merkulova VM, Ilovaisky AI, Terent’ev AO. Heterogeneous Photocatalysis as a Potent Tool for Organic Synthesis: Cross-Dehydrogenative C-C Coupling of N-Heterocycles with Ethers Employing TiO 2/ N-Hydroxyphthalimide System under Visible Light. Molecules 2023; 28:molecules28030934. [PMID: 36770603 PMCID: PMC9920906 DOI: 10.3390/molecules28030934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Despite the obvious advantages of heterogeneous photocatalysts (availability, stability, recyclability, the ease of separation from products and safety) their application in organic synthesis faces serious challenges: generally low efficiency and selectivity compared to homogeneous photocatalytic systems. The development of strategies for improving the catalytic properties of semiconductor materials is the key to their introduction into organic synthesis. In the present work, a hybrid photocatalytic system involving both heterogeneous catalyst (TiO2) and homogeneous organocatalyst (N-hydroxyphthalimide, NHPI) was proposed for the cross-dehydrogenative C-C coupling of electron-deficient N-heterocycles with ethers employing t-BuOOH as the terminal oxidant. It should be noted that each of the catalysts is completely ineffective when used separately under visible light in this transformation. The occurrence of visible light absorption upon the interaction of NHPI with the TiO2 surface and the generation of reactive phthalimide-N-oxyl (PINO) radicals upon irradiation with visible light are considered to be the main factors determining the high catalytic efficiency. The proposed method is suitable for the coupling of π-deficient pyridine, quinoline, pyrazine, and quinoxaline heteroarenes with various non-activated ethers.
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6
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Abstract
The quest to find milder and more sustainable methods to generate highly reactive, carbon-centred intermediates has led to a resurgence of interest in radical chemistry. In particular, carboxylic acids are seen as attractive radical precursors due their availability, low cost, diversity, and sustainability. Moreover, the corresponding nucleophilic carbon-radical can be easily accessed through a favourable radical decarboxylation process, extruding CO2 as a traceless by-product. This review summarizes the recent progress on using carboxylic acids directly as convenient radical precursors for the formation of carbon-carbon bonds via the 1,4-radical conjugate addition (Giese) reaction.
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Affiliation(s)
- David M Kitcatt
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - Simon Nicolle
- GlaxoSmithKline, Gunnels Wood Rd, Stevenage SG1 2NY, UK
| | - Ai-Lan Lee
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
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7
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Kuwana D, Komori Y, Nagatomo M, Inoue M. Photoinduced Decarboxylative Radical Coupling Reaction of Multiply Oxygenated Structures by Catalysis of Pt-Doped TiO 2. J Org Chem 2021; 87:730-736. [PMID: 34936365 DOI: 10.1021/acs.joc.1c02736] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new reaction system was devised for decarboxylative radical coupling reactions by heterogeneous semiconductor photoredox catalysis. When an α-alkoxy carboxylic acid and Pt-doped TiO2 in EtOAc were irradiated with a violet light-emitting diode at room temperature, the photogenerated electron hole of TiO2 oxidatively induced the ejection of CO2 via the formation of a carboxyl radical to produce the corresponding α-alkoxy radical. C(sp3)-C(sp3) bond formation between the radicals led to dimers with reductive conversion of protons to H2 by the photogenerated electron. Alternatively, in the presence of an electron-deficient olefin, an intermolecular radical addition reaction occurred, resulting in the formation of a 1,4-adduct via single-electron reduction and subsequent protonation. These operationally simple and mild transformations are amenable to the one-step assembly of densely oxygenated linear and branched carbon chains.
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Affiliation(s)
- Daiki Kuwana
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yuma Komori
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masanori Nagatomo
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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8
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Okada Y. Synthetic Semiconductor Photoelectrochemistry. CHEM REC 2021; 21:2223-2238. [PMID: 33769685 DOI: 10.1002/tcr.202100029] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/10/2021] [Indexed: 01/06/2023]
Abstract
In the field of synthetic organic chemistry, photochemical and electrochemical approaches are often considered to be competing technologies that induce single electron transfer (SET). Recently, their fusion, i. e., the "photoelectrochemical" approach, has become the focus of attention. In this approach, both solar and electrical energy are used in creative combinations. Historically, the term "photoelectrochemistry" has been used in more inorganic fields, where a photovoltaic effect exhibited by semiconducting materials is employed. Semiconductors have also been studied intensively as photocatalysts; however, they recently have taken a back seat to molecular photocatalysts. In this account, we would like to revisit semiconductor photocatalysts in the field of synthetic organic chemistry to demonstrate that semiconductor "photoelectrochemical" approaches are more than mere alternatives to molecular photochemical and/or electrochemical approaches.
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Affiliation(s)
- Yohei Okada
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, 184-8588, Japan
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9
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Andreev S, Pantsar T, El-Gokha A, Ansideri F, Kudolo M, Anton DB, Sita G, Romasco J, Geibel C, Lämmerhofer M, Goettert MI, Tarozzi A, Laufer SA, Koch P. Discovery and Evaluation of Enantiopure 9 H-pyrimido[4,5- b]indoles as Nanomolar GSK-3β Inhibitors with Improved Metabolic Stability. Int J Mol Sci 2020; 21:ijms21217823. [PMID: 33105671 PMCID: PMC7659979 DOI: 10.3390/ijms21217823] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 12/25/2022] Open
Abstract
Glycogen synthase kinase-3β (GSK-3β) is a potential target in the field of Alzheimer's disease drug discovery. We recently reported a new class of 9H-pyrimido[4,5-b]indole-based GSK-3β inhibitors, of which 3-(3-((7-chloro-9H-pyrimido[4,5-b]indol-4-yl)(methyl)amino)piperidin-1-yl)propanenitrile (1) demonstrated promising inhibitory potency. However, this compound underwent rapid degradation by human liver microsomes. Starting from 1, we prepared a series of amide-based derivatives and studied their structure-activity relationships against GSK-3β supported by 1 µs molecular dynamics simulations. The biological potency of this series was substantially enhanced by identifying the eutomer configuration at the stereocenter. Moreover, the introduction of an amide bond proved to be an effective strategy to eliminate the metabolic hotspot. The most potent compounds, (R)-3-(3-((7-chloro-9H-pyrimido[4,5-b]indol-4-yl)(methyl)amino)piperidin-1-yl)-3-oxopropanenitrile ((R)-2) and (R)-1-(3-((7-bromo-9Hpyrimido[4,5-b]indol-4-yl)(methyl)amino)piperidin-1-yl)propan-1-one ((R)-28), exhibited IC50 values of 480 nM and 360 nM, respectively, and displayed improved metabolic stability. Their favorable biological profile is complemented by minimal cytotoxicity and neuroprotective properties.
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Affiliation(s)
- Stanislav Andreev
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
| | - Tatu Pantsar
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Ahmed El-Gokha
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
- Chemistry Department, Faculty of Science, Menoufia University, Gamal Abdel-Nasser Street, Shebin El-Kom 32511, Egypt
| | - Francesco Ansideri
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
| | - Mark Kudolo
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
| | - Débora Bublitz Anton
- Cell Culture Laboratory, Postgraduate Program in Biotechnology, University of Vale do Taquari (Univates), Lajeado 95914-014, Brazil; (D.B.A.); (M.I.G.)
| | - Giulia Sita
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio, 48, 40126 Bologna, Italy;
| | - Jenny Romasco
- Department for Life Quality Studies, Alma Mater Studiorum, University of Bologna, Corso D’Augusto, 237, 47921 Rimini, Italy; (J.R.); (A.T.)
| | - Christian Geibel
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical (Bio-)Analysis, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (C.G.); (M.L.)
| | - Michael Lämmerhofer
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical (Bio-)Analysis, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (C.G.); (M.L.)
| | - Márcia Ines Goettert
- Cell Culture Laboratory, Postgraduate Program in Biotechnology, University of Vale do Taquari (Univates), Lajeado 95914-014, Brazil; (D.B.A.); (M.I.G.)
| | - Andrea Tarozzi
- Department for Life Quality Studies, Alma Mater Studiorum, University of Bologna, Corso D’Augusto, 237, 47921 Rimini, Italy; (J.R.); (A.T.)
| | - Stefan A. Laufer
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
| | - Pierre Koch
- Institute of Pharmaceutical Sciences, Department of Medicinal and Pharmaceutical Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany; (S.A.); (T.P.); (A.E.-G.); (F.A.); (M.K.); (S.A.L.)
- Department of Pharmaceutical/Medicinal Chemistry II, Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
- Correspondence: ; Tel.: +49-(941)-943-2847
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10
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Zhu Q, Nocera DG. Photocatalytic Hydromethylation and Hydroalkylation of Olefins Enabled by Titanium Dioxide Mediated Decarboxylation. J Am Chem Soc 2020; 142:17913-17918. [PMID: 32945670 DOI: 10.1021/jacs.0c08688] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A versatile method for the hydromethylation and hydroalkylation of alkenes at room temperature is achieved by using the photooxidative redox capacity of the valence band of anatase titanium dioxide (TiO2). Mechanistic studies support a radical-based mechanism involving the photoexcitation of TiO2 with 390 nm light in the presence of acetic acid and other carboxylic acids to generate methyl and alkyl radicals, respectively, without the need for stoichiometric base. This protocol is accepting of a broad scope of alkene and carboxylic acids, including challenging ones that produce highly reactive primary alkyl radicals and those containing functional groups that are susceptible to nucleophilic substitution such as alkyl halides. This methodology highlights the utility of using heterogeneous semiconductor photocatalysts such as TiO2 for promoting challenging organic syntheses that rely on highly reactive intermediates.
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Affiliation(s)
- Qilei Zhu
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138-2902, United States
| | - Daniel G Nocera
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138-2902, United States
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11
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Laudadio G, Deng Y, van der Wal K, Ravelli D, Nuño M, Fagnoni M, Guthrie D, Sun Y, Noël T. C(sp3)–H functionalizations of light hydrocarbons using decatungstate photocatalysis in flow. Science 2020; 369:92-96. [DOI: 10.1126/science.abb4688] [Citation(s) in RCA: 158] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/06/2020] [Indexed: 12/13/2022]
Abstract
Direct activation of gaseous hydrocarbons remains a major challenge for the chemistry community. Because of the intrinsic inertness of these compounds, harsh reaction conditions are typically required to enable C(sp3)–H bond cleavage, barring potential applications in synthetic organic chemistry. Here, we report a general and mild strategy to activate C(sp3)–H bonds in methane, ethane, propane, and isobutane through hydrogen atom transfer using inexpensive decatungstate as photocatalyst at room temperature. The corresponding carbon-centered radicals can be effectively trapped by a variety of Michael acceptors, leading to the corresponding hydroalkylated adducts in good isolated yields and high selectivity (38 examples).
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Affiliation(s)
- Gabriele Laudadio
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Yuchao Deng
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven, Netherlands
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, P. R. China
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, P. R. China
| | - Klaas van der Wal
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Davide Ravelli
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Pavia 27100, Italy
| | - Manuel Nuño
- Vapourtec, Fornham St Genevieve, Bury St Edmunds, Suffolk IP28 6TS, UK
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Pavia 27100, Italy
| | - Duncan Guthrie
- Vapourtec, Fornham St Genevieve, Bury St Edmunds, Suffolk IP28 6TS, UK
| | - Yuhan Sun
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, P. R. China
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, P. R. China
| | - Timothy Noël
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven, Netherlands
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12
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Affiliation(s)
- Sebastian Gisbertz
- Department of Biomolecular SystemsMax Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
- Department of Chemistry and BiochemistryFreie Universität Berlin Arnimallee 22 14195 Berlin Germany
| | - Bartholomäus Pieber
- Department of Biomolecular SystemsMax Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
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13
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Miyabe H, Kohtani S. Photocatalytic single electron transfer reactions on TiO2 semiconductor. Sci China Chem 2019. [DOI: 10.1007/s11426-019-9626-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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14
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Ozaki Y, Yamada T, Mizuno T, Osaka K, Yamawaki M, Maeda H, Morita T, Yoshimi Y. Retention of chirality of 5-membered alicyclic α-amino acids bearing N-(2-phenyl)benzoyl group in photoinduced decarboxylative intermolecular radical addition to acrylonitrile. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.130493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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15
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Osaka K, Usami A, Iwasaki T, Yamawaki M, Morita T, Yoshimi Y. Sequential Intermolecular Radical Addition and Reductive Radical Cyclization of Tyrosine and Phenylalanine Derivatives with Alkenes via Photoinduced Decarboxylation: Access to Ring-Constrained γ-Amino Acids. J Org Chem 2019; 84:9480-9488. [DOI: 10.1021/acs.joc.9b00970] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Kazuyuki Osaka
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Ayuka Usami
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Tomoya Iwasaki
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Mugen Yamawaki
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Toshio Morita
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Yasuharu Yoshimi
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
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16
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Nakayama K, Maeta N, Horiguchi G, Kamiya H, Okada Y. Radical Cation Diels-Alder Reactions by TiO 2 Photocatalysis. Org Lett 2019; 21:2246-2250. [PMID: 30916982 DOI: 10.1021/acs.orglett.9b00526] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Radical cation Diels-Alder reactions by titanium dioxide (TiO2) photocatalysis in lithium perchlorate/nitromethane solution are described. TiO2 photocatalysis promotes reactions between electron-rich dienes and dienophiles, which would otherwise be difficult to accomplish due to electronic mismatching. The reactions are triggered by hole oxidation of the dienophile and are completed by the excited electron reduction of the radical cation intermediate at the dispersed surface in the absence of any sacrificial substrate.
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Affiliation(s)
- Kaii Nakayama
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei, Tokyo 184-8588 , Japan
| | - Naoya Maeta
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei, Tokyo 184-8588 , Japan
| | - Genki Horiguchi
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei, Tokyo 184-8588 , Japan
| | - Hidehiro Kamiya
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei, Tokyo 184-8588 , Japan
| | - Yohei Okada
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei, Tokyo 184-8588 , Japan
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17
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Ma D, Zhai S, Wang Y, Liu A, Chen C. TiO₂ Photocatalysis for Transfer Hydrogenation. Molecules 2019; 24:E330. [PMID: 30658472 PMCID: PMC6358817 DOI: 10.3390/molecules24020330] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/11/2019] [Accepted: 01/15/2019] [Indexed: 12/02/2022] Open
Abstract
Catalytic transfer hydrogenation reactions, based on hydrogen sources other than gaseous H₂, are important processes that are preferential in both laboratories and factories. However, harsh conditions, such as high temperature, are usually required for most transition-metal catalytic and organocatalytic systems. Moreover, non-volatile hydrogen donors such as dihydropyridinedicarboxylate and formic acid are often required in these processes which increase the difficulty in separating products and lowered the whole atom economy. Recently, TiO₂ photocatalysis provides mild and facile access for transfer hydrogenation of C=C, C=O, N=O and C-X bonds by using volatile alcohols and amines as hydrogen sources. Upon light excitation, TiO₂ photo-induced holes have the ability to oxidatively take two hydrogen atoms off alcohols and amines under room temperature. Simultaneously, photo-induced conduction band electrons would combine with these two hydrogen atoms and smoothly hydrogenate multiple bonds and/or C-X bonds. It is heartening that practices and principles in the transfer hydrogenations of substrates containing C=C, C=O, N=O and C-X bond based on TiO₂ photocatalysis have overcome a lot of the traditional thermocatalysis' limitations and flaws which usually originate from high temperature operations. In this review, we will introduce the recent paragon examples of TiO₂ photocatalytic transfer hydrogenations used in (1) C=C and C≡C (2) C=O and C=N (3) N=O substrates and in-depth discuss basic principle, status, challenges and future directions of transfer hydrogenation mediated by TiO₂ photocatalysis.
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Affiliation(s)
- Dongge Ma
- School of Science, Beijing Technology and Business University, Beijing 100048, China.
| | - Shan Zhai
- School of Science, Beijing Technology and Business University, Beijing 100048, China.
| | - Yi Wang
- School of Science, Beijing Technology and Business University, Beijing 100048, China.
| | - Anan Liu
- Basic Experimental Center for Natural Science, University of Science and Technology Beijing, Beijing 100083, China.
| | - Chuncheng Chen
- Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
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18
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Riente P, Noël T. Application of metal oxide semiconductors in light-driven organic transformations. Catal Sci Technol 2019. [DOI: 10.1039/c9cy01170f] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Herein, we provide an up-to-date overview of metal oxide semiconductors (MOS) as versatile and inexpensive photocatalysts to enable light-driven organic transformations.
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Affiliation(s)
- Paola Riente
- Micro Flow Chemistry and Synthetic Methodology
- Department of Chemical Engineering and Chemistry
- Eindhoven University of Technology
- Eindhoven
- The Netherlands
| | - Timothy Noël
- Micro Flow Chemistry and Synthetic Methodology
- Department of Chemical Engineering and Chemistry
- Eindhoven University of Technology
- Eindhoven
- The Netherlands
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19
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Cheng H, Xu W. Recent advances in modified TiO2 for photo-induced organic synthesis. Org Biomol Chem 2019; 17:9977-9989. [DOI: 10.1039/c9ob01739a] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The recent advancements of modified TiO2 materials as photocatalysts for organic synthesis are summarized.
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Affiliation(s)
- Haojie Cheng
- School of Information Management
- Nanjing University
- Nanjing 210023
- China
| | - Wentao Xu
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
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20
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Tarantino G, Hammond C. Catalytic Formation of C(sp3)–F Bonds via Heterogeneous Photocatalysis. ACS Catal 2018. [DOI: 10.1021/acscatal.8b02844] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Giulia Tarantino
- Cardiff Catalysis Institute, Cardiff University, Park Place, Cardiff CF10 3AT, U.K
| | - Ceri Hammond
- Cardiff Catalysis Institute, Cardiff University, Park Place, Cardiff CF10 3AT, U.K
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21
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Okada Y, Maeta N, Nakayama K, Kamiya H. TiO 2 Photocatalysis in Aromatic "Redox Tag"-Guided Intermolecular Formal [2 + 2] Cycloadditions. J Org Chem 2018; 83:4948-4962. [PMID: 29656651 DOI: 10.1021/acs.joc.8b00738] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Since the pioneering work by Macmillan, Yoon, and Stephenson, homogeneous photoredox catalysis has occupied a central place in new reaction development in the field of organic chemistry. While heterogeneous semiconductor photocatalysis has also been studied extensively, it has generally been recognized as a redox option in inorganic chemistry where such "photocatalysis" is most often used to catalyze carbon-carbon bond cleavage and not in organic chemistry where bond formation is usually the focal point. Herein, we demonstrate that titanium dioxide photocatalysis is a powerful redox option to construct carbon-carbon bonds by using intermolecular formal [2 + 2] cycloadditions as models. Synergy between excited electrons and holes generated upon irradiation is expected to promote the overall net redox neutral process. Key for the successful application is the use of a lithium perchlorate/nitromethane electrolyte solution, which exhibits remarkable Lewis acidity to facilitate the reactions of carbon-centered radical cations with carbon nucleophiles. The reaction mechanism is reasonably understood based on both intermolecular and intramolecular single electron transfer regulated by an aromatic "redox tag". Most of the reactions were completed in less than 30 min even in aqueous and/or aerobic conditions without the need for sacrificial reducing or oxidizing substrates generally required for homogeneous photoredox catalysis.
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Affiliation(s)
- Yohei Okada
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
| | - Naoya Maeta
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
| | - Kaii Nakayama
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
| | - Hidehiro Kamiya
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
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22
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Abstract
Synergistic utilization of TiO2-photo-generated holes and electrons is a potential protocol for catalytic C–C bond formation reactions.
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Affiliation(s)
- Dongge Ma
- School of Science
- Beijing Technology and Business University
- Beijing
- P. R. China
| | - Anan Liu
- Key Laboratory of Photochemistry
- Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry, Chinese Academy of Sciences
- Beijing
- P. R. China
| | - Shuhong Li
- School of Science
- Beijing Technology and Business University
- Beijing
- P. R. China
| | - Chichong Lu
- School of Science
- Beijing Technology and Business University
- Beijing
- P. R. China
| | - Chuncheng Chen
- Key Laboratory of Photochemistry
- Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry, Chinese Academy of Sciences
- Beijing
- P. R. China
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23
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Ma D, Liu A, Lu C, Chen C. Photocatalytic Dehydrogenation of Primary Alcohols: Selectivity Goes against Adsorptivity. ACS OMEGA 2017; 2:4161-4172. [PMID: 31457713 PMCID: PMC6641877 DOI: 10.1021/acsomega.7b00754] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 07/19/2017] [Indexed: 05/17/2023]
Abstract
Solid/liquid heterogeneous photocatalysis was often considered to occur on the active sites of a solid catalyst surface. Herein, we report that the selectivity of photocatalytic dehydrogenative oxidations of aliphatic primary alcohols in acetonitrile solution into corresponding aldehydes exhibits an anomalous relationship with adsorption behavior of the alcohols. By using Pt-loaded TiO2 photocatalyst in an inert atmosphere under UV light illumination, primary short-chain alcohols (SCAs) with strong adsorption were dehydrogenated into aldehydes in very poor selectivity, whereas weak-adsorbable long-chain alcohols (LCAs) were transformed into corresponding aldehydes with much higher selectivity. More than 20 examples of primary LCAs (C4-C10) were successfully transformed into their corresponding aldehydes with satisfactory selectivity and yield. Both solid-state magic-angle-spinning 13C NMR and attenuated total reflectance-Fourier transform infrared spectroscopy studies provided concrete differences in adsorption behaviors on the Pt-TiO2 photocatalyst surface between SCA ethanol and LCA n-octanol. To further uncover the mechanism for different selectivities of SCAs and LCAs in photodehydrogenation, in situ electron paramagnetic resonance (EPR) experiments (at 8 K temperature) were employed to observe the oxidation features of photogenerated hole in the valance band of Pt-TiO2 (hvb +). The EPR experimental studies exhibited that unlike ethanol, either n-octanol or solvent acetonitrile alone all could not scavenge photogenerated hvb + on Pt-P25 photocatalyst and only n-octanol dissolved in acetonitrile solvent could smoothly react with photoinduced hole. This indicated that selective oxidations of LCAs were achieved by solvent-delivered oxidation rather than directly destructive oxidation of photogenerated hvb +. Our results may open an alternative way in selective dehydrogenative oxidation of various substrates sensitive to both dioxygen and high-temperature treatments.
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Affiliation(s)
- Dongge Ma
- School
of Science, Beijing Technology and Business
University, 100048 Beijing, P. R. China
- Key
Laboratory of Photochemistry, Beijing National Laboratory for Molecular
Sciences, Institute of Chemistry, Chinese
Academy of Sciences, 100190 Beijing, P. R. China
- University
of Chinese Academy of Sciences, Beijing 100049, P. R.
China
- E-mail: . Phone: +86-10-68985573 (D.M.)
| | - Anan Liu
- Key
Laboratory of Photochemistry, Beijing National Laboratory for Molecular
Sciences, Institute of Chemistry, Chinese
Academy of Sciences, 100190 Beijing, P. R. China
- University
of Chinese Academy of Sciences, Beijing 100049, P. R.
China
| | - Chichong Lu
- School
of Science, Beijing Technology and Business
University, 100048 Beijing, P. R. China
| | - Chuncheng Chen
- Key
Laboratory of Photochemistry, Beijing National Laboratory for Molecular
Sciences, Institute of Chemistry, Chinese
Academy of Sciences, 100190 Beijing, P. R. China
- University
of Chinese Academy of Sciences, Beijing 100049, P. R.
China
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24
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Yoshimi Y. Photoinduced electron transfer-promoted decarboxylative radical reactions of aliphatic carboxylic acids by organic photoredox system. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2017.04.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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25
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Yamawaki M, Ukai A, Kamiya Y, Sugihara S, Sakai M, Yoshimi Y. Metal-Free Photoinduced Decarboxylative Radical Polymerization Using Carboxylic Acids as Benign Radical Initiators: Introduction of Complex Molecules into Polymer Chain Ends. ACS Macro Lett 2017; 6:381-385. [PMID: 35610853 DOI: 10.1021/acsmacrolett.7b00193] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Metal-free photoinduced decarboxylative radical polymerization of aliphatic carboxylic acids with a variety of monomers was found to proceed smoothly to give the corresponding polymers under mild conditions. Complex carboxylic acids such as those of sugars, steroids, and peptides can function as benign radical initiators via decarboxylation and can be incorporated at the polymer chain ends. This synthetic methodology represents a facile introduction of molecules and functionalities to polymers by using commercially available carboxylic acids.
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Affiliation(s)
- Mugen Yamawaki
- Department of Applied
Chemistry
and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Akari Ukai
- Department of Applied
Chemistry
and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Yuki Kamiya
- Department of Applied
Chemistry
and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Shinji Sugihara
- Department of Applied
Chemistry
and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Miku Sakai
- Department of Applied
Chemistry
and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
| | - Yasuharu Yoshimi
- Department of Applied
Chemistry
and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
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26
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McTiernan CD, Leblanc X, Scaiano JC. Heterogeneous Titania-Photoredox/Nickel Dual Catalysis: Decarboxylative Cross-Coupling of Carboxylic Acids with Aryl Iodides. ACS Catal 2017. [DOI: 10.1021/acscatal.6b03687] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Christopher D. McTiernan
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Xavier Leblanc
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Juan C. Scaiano
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
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27
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Affiliation(s)
- Norbert Hoffmann
- CNRS Université de Reims Champagne-Ardenne; ICMR; Université de Reims Champagne-Ardenne; B.P. 1039 51687 Reims France
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28
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Peng F, Zhi P, Ji H, Zhao H, Kong FY, Liang XZ, Shen YM. Visible light mediated cyclization of tertiary anilines with maleimides using a supported iridium complex catalyst. RSC Adv 2017. [DOI: 10.1039/c7ra01045a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The synthesis of a novel supported iridium complex catalyst and its efficient application in the visible light mediated cyclization of tertiary anilines and maleimides.
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Affiliation(s)
- Feng Peng
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province
- School of Chemistry and Chemical Engineering
- Shaoxing University
- Shaoxing 312000
- China
| | - Peng Zhi
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province
- School of Chemistry and Chemical Engineering
- Shaoxing University
- Shaoxing 312000
- China
| | - Heng Ji
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province
- School of Chemistry and Chemical Engineering
- Shaoxing University
- Shaoxing 312000
- China
| | - Huan Zhao
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province
- School of Chemistry and Chemical Engineering
- Shaoxing University
- Shaoxing 312000
- China
| | - Fen-Ying Kong
- School of Chemistry and Chemical Engineering
- Yancheng Institute of Technology
- China
| | - Xue-Zheng Liang
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province
- School of Chemistry and Chemical Engineering
- Shaoxing University
- Shaoxing 312000
- China
| | - Yong-Miao Shen
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province
- School of Chemistry and Chemical Engineering
- Shaoxing University
- Shaoxing 312000
- China
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29
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Lipp B, Nauth AM, Opatz T. Transition-Metal-Free Decarboxylative Photoredox Coupling of Carboxylic Acids and Alcohols with Aromatic Nitriles. J Org Chem 2016; 81:6875-82. [PMID: 27399619 DOI: 10.1021/acs.joc.6b01215] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A transition-metal-free protocol for the redox-neutral light-induced decarboxylative coupling of carboxylic acids with (hetero)aromatic nitriles at ambient temperature is presented. A broad scope of acids and nitriles is accepted, and alcohols can be coupled in a similar fashion through their oxalate half esters. Various inexpensive sources of UV light and even sunlight can be used to achieve this C-C bond formation proceeding through a free radical mechanism.
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Affiliation(s)
- Benjamin Lipp
- Institute of Organic Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Alexander M Nauth
- Institute of Organic Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Till Opatz
- Institute of Organic Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany
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30
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Capaldo L, Buzzetti L, Merli D, Fagnoni M, Ravelli D. Smooth Photocatalyzed Benzylation of Electrophilic Olefins via Decarboxylation of Arylacetic Acids. J Org Chem 2016; 81:7102-9. [DOI: 10.1021/acs.joc.6b00984] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Luca Capaldo
- PhotoGreen Lab, Department
of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Luca Buzzetti
- PhotoGreen Lab, Department
of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Daniele Merli
- PhotoGreen Lab, Department
of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department
of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Davide Ravelli
- PhotoGreen Lab, Department
of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
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31
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Cano R, Pérez JM, Ramón DJ, McGlacken GP. Impregnated palladium on magnetite as catalyst for direct arylation of heterocycles. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.12.039] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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32
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Walton JC. Functionalised Oximes: Emergent Precursors for Carbon-, Nitrogen- and Oxygen-Centred Radicals. Molecules 2016; 21:63. [PMID: 26751437 PMCID: PMC6273297 DOI: 10.3390/molecules21010063] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 12/29/2015] [Accepted: 12/30/2015] [Indexed: 11/16/2022] Open
Abstract
Oxime derivatives are easily made, are non-hazardous and have long shelf lives. They contain weak N-O bonds that undergo homolytic scission, on appropriate thermal or photochemical stimulus, to initially release a pair of N- and O-centred radicals. This article reviews the use of these precursors for studying the structures, reactions and kinetics of the released radicals. Two classes have been exploited for radical generation; one comprises carbonyl oximes, principally oxime esters and amides, and the second comprises oxime ethers. Both classes release an iminyl radical together with an equal amount of a second oxygen-centred radical. The O-centred radicals derived from carbonyl oximes decarboxylate giving access to a variety of carbon-centred and nitrogen-centred species. Methods developed for homolytically dissociating the oxime derivatives include UV irradiation, conventional thermal and microwave heating. Photoredox catalytic methods succeed well with specially functionalised oximes and this aspect is also reviewed. Attention is also drawn to the key contributions made by EPR spectroscopy, aided by DFT computations, in elucidating the structures and dynamics of the transient intermediates.
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Affiliation(s)
- John C Walton
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, Fife KY16 9ST, UK.
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33
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Yoshimitsu T. Radical Cyclization Strategies in Total Syntheses of Bioactive Fused Cyclic Natural Products. J SYN ORG CHEM JPN 2016. [DOI: 10.5059/yukigoseikyokaishi.74.350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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34
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Lefebvre Q, Hoffmann N, Rueping M. Photoorganocatalysed and visible light photoredox catalysed trifluoromethylation of olefins and (hetero)aromatics in batch and continuous flow. Chem Commun (Camb) 2016; 52:2493-6. [DOI: 10.1039/c5cc09881e] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Trifluoromethylation of olefins and (hetero)aromatics with sodium triflinate as CF3source and readily accessible benzophenone derivatives as photosensitisers has been developed in batch and flow.
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Affiliation(s)
| | - Norbert Hoffmann
- CNRS
- Université de Reims Champagne-Ardenne Institut de Chimie Moléculaire de Reims (UMR 6229)
- Equipe de Photochimie
- UFR Sciences
- France
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35
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LeBlanc LM, Crowell AMJ, Grossert JS, White RL. Phenyl group participation in rearrangements during collision-induced dissociation of deprotonated phenoxyacetic acid. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:2293-2301. [PMID: 26522323 DOI: 10.1002/rcm.7395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 08/11/2015] [Accepted: 09/10/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE The identification of trace constituents in biological and environmental samples is frequently based on the fragmentation patterns resulting from the collision-induced dissociation (CID) of gas-phase ions. Credible mechanistic characterization of fragmentation processes, including rearrangements, is required to make reliable assignments for structures of precursor and product ions. METHODS Mass spectra were collected using both ion trap and triple quadrupole mass spectrometers operating in the negative ion mode. Precursor ion scans and CID of ions generated in-source were used to establish precursor-product ion relationships. Density functional theory (DFT) computations were performed at the MP2/6-311++G(2d,p)//B3LYP/6-31++G(2d,p) level of theory. RESULTS Product ions at m/z 93 and 107 obtained upon CID of phenoxyacetate were attributed to phenoxide and o-methylphenoxide, respectively. An isotopic labeling experiment and computations showed that the phenoxide ion was formed by intramolecular displacement with formation of an α-lactone and also by a Smiles rearrangement. Rearrangement of phenoxyacetate via the ion-neutral complex formed in the α-lactone displacement pathway gave the isomeric o-hydroxyphenylacetate ion which yielded o-methylphenoxide upon decarboxylation. Computations provided feasible energetics for these pathways. CONCLUSIONS Previously unrecognized and energetically favorable rearrangements during the collision-induced fragmentation of phenoxyacetate have been characterized using isotopic labeling and DFT computations. Notably, the phenyl substituent plays an indispensable role in each rearrangement process resulting in multiple pathways for the fragmentation of phenoxyacetate.
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Affiliation(s)
- Luc M LeBlanc
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Andrew M J Crowell
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, B3H 4R2, Canada
| | - J Stuart Grossert
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Robert L White
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, B3H 4R2, Canada
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36
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Manley DW, Walton JC. Preparative semiconductor photoredox catalysis: An emerging theme in organic synthesis. Beilstein J Org Chem 2015; 11:1570-82. [PMID: 26664577 PMCID: PMC4660884 DOI: 10.3762/bjoc.11.173] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 08/19/2015] [Indexed: 11/23/2022] Open
Abstract
Heterogeneous semiconductor photoredox catalysis (SCPC), particularly with TiO2, is evolving to provide radically new synthetic applications. In this review we describe how photoactivated SCPCs can either (i) interact with a precursor that donates an electron to the semiconductor thus generating a radical cation; or (ii) interact with an acceptor precursor that picks up an electron with production of a radical anion. The radical cations of appropriate donors convert to neutral radicals usually by loss of a proton. The most efficient donors for synthetic purposes contain adjacent functional groups such that the neutral radicals are resonance stabilized. Thus, ET from allylic alkenes and enol ethers generated allyl type radicals that reacted with 1,2-diazine or imine co-reactants to yield functionalized hydrazones or benzylanilines. SCPC with tertiary amines enabled electron-deficient alkenes to be alkylated and furoquinolinones to be accessed. Primary amines on their own led to self-reactions involving C-N coupling and, with terminal diamines, cyclic amines were produced. Carboxylic acids were particularly fruitful affording C-centered radicals that alkylated alkenes and took part in tandem addition cyclizations producing chromenopyrroles; decarboxylative homo-dimerizations were also observed. Acceptors initially yielding radical anions included nitroaromatics and aromatic iodides. The latter led to hydrodehalogenations and cyclizations with suitable precursors. Reductive SCPC also enabled electron-deficient alkenes and aromatic aldehydes to be hydrogenated without the need for hydrogen gas.
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Affiliation(s)
- David W Manley
- University of St. Andrews, EaStCHEM School of Chemistry, St. Andrews, Fife, KY16 9ST, UK
| | - John C Walton
- University of St. Andrews, EaStCHEM School of Chemistry, St. Andrews, Fife, KY16 9ST, UK
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37
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Zhou QQ, Guo W, Ding W, Wu X, Chen X, Lu LQ, Xiao WJ. Decarboxylative Alkynylation and Carbonylative Alkynylation of Carboxylic Acids Enabled by Visible-Light Photoredox Catalysis. Angew Chem Int Ed Engl 2015; 54:11196-9. [DOI: 10.1002/anie.201504559] [Citation(s) in RCA: 255] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 06/17/2015] [Indexed: 01/08/2023]
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38
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Zhou QQ, Guo W, Ding W, Wu X, Chen X, Lu LQ, Xiao WJ. Decarboxylative Alkynylation and Carbonylative Alkynylation of Carboxylic Acids Enabled by Visible-Light Photoredox Catalysis. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504559] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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39
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Riente P, Pericàs MA. Visible Light-Driven Atom Transfer Radical Addition to Olefins using Bi2 O3 as Photocatalyst. CHEMSUSCHEM 2015; 8:1841-1844. [PMID: 25925199 DOI: 10.1002/cssc.201403466] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Revised: 03/01/2015] [Indexed: 06/04/2023]
Abstract
Bismuth oxide, an inexpensive and non-toxic semiconductor, has been successfully used as a visible light photocatalyst for the atom transfer radical addition (ATRA) reaction of organobromides to diversely functionalized terminal olefins. The reaction takes place under very mild conditions, in the absence of any additive, and with low catalyst loading (1 mol %). The corresponding ATRA products are obtained with moderate to excellent yields (up to 95 %).
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Affiliation(s)
- Paola Riente
- Institute of Chemical Research of Catalonia (ICIQ), Avda. Països Catalans, 16. 43007 Tarragona (Spain)
| | - Miquel A Pericàs
- Institute of Chemical Research of Catalonia (ICIQ), Avda. Països Catalans, 16. 43007 Tarragona (Spain). ,
- Department de Química Orgànica, Universitat de Barcelona c/ Martì i Franqués 1 - 11, 08028 - Barcelona (Spain). ,
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40
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Rhydderch S, Howe RF. In situ EPR studies of reaction pathways in Titania photocatalyst-promoted alkylation of alkenes. Molecules 2015; 20:4055-70. [PMID: 25741899 PMCID: PMC6272746 DOI: 10.3390/molecules20034055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/17/2015] [Accepted: 02/26/2015] [Indexed: 11/16/2022] Open
Abstract
In situ EPR spectroscopy at cryogenic temperatures has been used to observe and identify paramagnetic species produced when titania is irradiated in the presence of reactants used in the photocatalytic alkylation of maleimide with t-butyl carboxylic acid or phenoxyacetic acid. It is shown that maleimide acts as an acceptor of conduction band electrons. Valence band holes oxidise t-butyl carboxylic acid to the t-butyl radical and phenoxyacetic acid to the phenoxyacetic acid radical cation. In the presence of maleimide, the phenoxymethyl radical is formed from phenoxyacetic acid. The relevance of these observations to the mechanisms of titania photocatalyst-promoted alkylation of alkenes is discussed.
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Affiliation(s)
- Shona Rhydderch
- Chemistry Department, University of Aberdeen, Aberdeen AB24 3UE, UK.
| | - Russell F Howe
- Chemistry Department, University of Aberdeen, Aberdeen AB24 3UE, UK.
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41
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Saito H, Kanetake T, Osaka K, Maeda K, Morita T, Yoshimi Y. A strategy for generating alkyl radicals from aliphatic esters and lactones via sequential hydrolysis and photoinduced decarboxylation. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.02.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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42
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Tang J, Grampp G, Liu Y, Wang BX, Tao FF, Wang LJ, Liang XZ, Xiao HQ, Shen YM. Visible Light Mediated Cyclization of Tertiary Anilines with Maleimides Using Nickel(II) Oxide Surface-Modified Titanium Dioxide Catalyst. J Org Chem 2015; 80:2724-32. [DOI: 10.1021/jo502901h] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Jian Tang
- Key
Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province,
School of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China
| | - Günter Grampp
- Physical
and Theoretical Chemistry, Graz University of Technology, Stremayrgasse
9/Z2, A-8010 Graz, Austria
| | - Yun Liu
- Jiangsu
Key Laboratory of Green Synthetic for Functional Materials, School
of Chemistry and Chemical Engineering, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China
| | - Bing-Xiang Wang
- Jiangsu
Key Laboratory of Biofunctional Materials, School of Chemistry and
Materials Science, Nanjing Normal University, Nanjing 210097, China
| | - Fei-Fei Tao
- Key
Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province,
School of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China
| | - Li-Jun Wang
- Key
Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province,
School of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China
| | - Xue-Zheng Liang
- Key
Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province,
School of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China
| | - Hui-Quan Xiao
- Key
Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province,
School of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China
| | - Yong-Miao Shen
- Key
Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province,
School of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, China
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43
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Walton JC, Williams F. The games radicals play: special issue on free radicals and radical ions. Molecules 2015; 20:2831-4. [PMID: 25671366 PMCID: PMC6272344 DOI: 10.3390/molecules20022831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/05/2015] [Indexed: 11/16/2022] Open
Affiliation(s)
- John C Walton
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews KY16 9ST, UK.
| | - Ffrancon Williams
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600, USA.
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44
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Maeda K, Saito H, Osaka K, Nishikawa K, Sugie M, Morita T, Takahashi I, Yoshimi Y. Direct modification of tripeptides using photoinduced decarboxylative radical reactions. Tetrahedron 2015. [DOI: 10.1016/j.tet.2014.12.075] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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45
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Bhat VT, Duspara PA, Seo S, Abu Bakar NSB, Greaney MF. Visible light promoted thiol-ene reactions using titanium dioxide. Chem Commun (Camb) 2015; 51:4383-5. [DOI: 10.1039/c4cc09987g] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thiol-ene chemistry under mild conditions is reported using titania as a cheap and user-friendly photoredox catalyst.
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Affiliation(s)
| | | | - Sangwon Seo
- School of Chemistry
- University of Manchester
- Manchester
- UK
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46
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Affiliation(s)
- Norbert Hoffmann
- CNRS, Université de Reims Champagne-Ardenne; ICMR, Equipe de Photochimie; UFR Sciences, B.P. 1039 51687 Reims France
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47
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Manley DW, Walton JC. A clean and selective radical homocoupling employing carboxylic acids with titania photoredox catalysis. Org Lett 2014; 16:5394-7. [PMID: 25290736 DOI: 10.1021/ol502625w] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A titania photoredox catalysis protocol was developed for the homocoupling of C-centered radicals derived from carboxylic acids. Intermolecular reactions were generally efficient and selective, furnishing the desired dimers in good yields under mild neutral conditions. Selective cross-coupling with two acids proved unsuccessful. An intramolecular adaptation enabled macrocycles to be prepared, albeit in modest yields.
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Affiliation(s)
- David W Manley
- University of St. Andrews , EaStCHEM School of Chemistry, St. Andrews, Fife, KY16 9ST, U.K
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48
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Manley DW, Buzzetti L, MacKessack-Leitch A, Walton JC. Hydrogenations without hydrogen: titania photocatalyzed reductions of maleimides and aldehydes. Molecules 2014; 19:15324-38. [PMID: 25255248 PMCID: PMC6270841 DOI: 10.3390/molecules190915324] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 09/16/2014] [Accepted: 09/17/2014] [Indexed: 11/20/2022] Open
Abstract
A mild procedure for the reduction of electron-deficient alkenes and carbonyl compounds is described. UVA irradiations of substituted maleimides with dispersions of titania (Aeroxide P25) in methanol/acetonitrile (1:9) solvent under dry anoxic conditions led to hydrogenation and production of the corresponding succinimides. Aromatic and heteroaromatic aldehydes were reduced to primary alcohols in similar titania photocatalyzed reactions. A mechanism is proposed which involves two proton-coupled electron transfers to the substrates at the titania surface.
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Affiliation(s)
- David W Manley
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, Fife KY16 9ST, UK.
| | - Luca Buzzetti
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, Fife KY16 9ST, UK.
| | | | - John C Walton
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, Fife KY16 9ST, UK.
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49
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McTiernan CD, Pitre SP, Ismaili H, Scaiano JC. Heterogeneous Light-Mediated Reductive Dehalogenations and Cyclizations Utilizing Platinum Nanoparticles on Titania (PtNP@TiO2). Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400547] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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