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Liang L, Wang YH, Li C, Wang HJ, Yang QL, Li CG, Qu GR, Guo HM, Niu HY. Regioselective and late-stage polyfluoroarylation of arenes with diverse fluoroaryl nucleophiles via Pd-catalysis. Org Chem Front 2022. [DOI: 10.1039/d2qo00991a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dehydrogenative coupling of arenes with fluoroaryl nucleophiles enables the efficient synthesis of fluoroaromatic compounds from readily available starting materials.
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Affiliation(s)
- Lei Liang
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
| | - Yue-Hui Wang
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
| | - Chen Li
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
| | - Hua-Jie Wang
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
| | - Qi-Liang Yang
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Chang-Gong Li
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
| | - Gui-Rong Qu
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Hai-Ming Guo
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Hong-Ying Niu
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
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2
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Abstract
A simple electrochemically mediated method for the conversion of alkyl carboxylic acids to their borylated congeners is presented. This protocol features an undivided cell setup with inexpensive carbon-based electrodes and exhibits a broad substrate scope and scalability in both flow and batch reactors. The use of this method in challenging contexts is exemplified with a modular formal synthesis of jawsamycin, a natural product harboring five cyclopropane rings.
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3
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Cook XAF, de Gombert A, McKnight J, Pantaine LRE, Willis MC. The 2-Pyridyl Problem: Challenging Nucleophiles in Cross-Coupling Arylations. Angew Chem Int Ed Engl 2021; 60:11068-11091. [PMID: 32940402 PMCID: PMC8246887 DOI: 10.1002/anie.202010631] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Indexed: 12/22/2022]
Abstract
Azine-containing biaryls are ubiquitous scaffolds in many areas of chemistry, and efficient methods for their synthesis are continually desired. Pyridine rings are prominent amongst these motifs. Transition-metal-catalysed cross-coupling reactions have been widely used for their synthesis and functionalisation as they often provide a swift and tuneable route to related biaryl scaffolds. However, 2-pyridine organometallics are capricious coupling partners and 2-pyridyl boron reagents in particular are notorious for their instability and poor reactivity in Suzuki-Miyaura cross-coupling reactions. The synthesis of pyridine-containing biaryls is therefore limited, and methods for the formation of unsymmetrical 2,2'-bis-pyridines are scarce. This Review focuses on the methods developed for the challenging coupling of 2-pyridine nucleophiles with (hetero)aryl electrophiles, and ranges from traditional cross-coupling processes to alternative nucleophilic reagents and novel main group approaches.
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Affiliation(s)
- Xinlan A. F. Cook
- Chemistry Research LaboratoryOxford University12 Mansfield RoadOxfordOX1 3TAUK
| | - Antoine de Gombert
- Chemistry Research LaboratoryOxford University12 Mansfield RoadOxfordOX1 3TAUK
| | - Janette McKnight
- Chemistry Research LaboratoryOxford University12 Mansfield RoadOxfordOX1 3TAUK
| | - Loïc R. E. Pantaine
- Chemistry Research LaboratoryOxford University12 Mansfield RoadOxfordOX1 3TAUK
| | - Michael C. Willis
- Chemistry Research LaboratoryOxford University12 Mansfield RoadOxfordOX1 3TAUK
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4
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Budiman YP, Westcott SA, Radius U, Marder TB. Fluorinated Aryl Boronates as Building Blocks in Organic Synthesis. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001291] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Yudha P. Budiman
- Institute for Inorganic Chemistry Julius-Maximilians University Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians University Würzburg Am Hubland 97074 Würzburg Germany
- Department of Chemistry Faculty of Mathematics and Natural Sciences Universitas Padjadjaran 45363 Jatinangor Indonesia
| | - Stephen A. Westcott
- Department of Chemistry and Biochemistry Mount Allison University Sackville NB E4 L 1G8 Canada
| | - Udo Radius
- Institute for Inorganic Chemistry Julius-Maximilians University Würzburg Am Hubland 97074 Würzburg Germany
| | - Todd B. Marder
- Institute for Inorganic Chemistry Julius-Maximilians University Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians University Würzburg Am Hubland 97074 Würzburg Germany
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5
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Cook XAF, Gombert A, McKnight J, Pantaine LRE, Willis MC. The 2‐Pyridyl Problem: Challenging Nucleophiles in Cross‐Coupling Arylations. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010631] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Xinlan A. F. Cook
- Chemistry Research Laboratory Oxford University 12 Mansfield Road Oxford OX1 3TA UK
| | - Antoine Gombert
- Chemistry Research Laboratory Oxford University 12 Mansfield Road Oxford OX1 3TA UK
| | - Janette McKnight
- Chemistry Research Laboratory Oxford University 12 Mansfield Road Oxford OX1 3TA UK
| | - Loïc R. E. Pantaine
- Chemistry Research Laboratory Oxford University 12 Mansfield Road Oxford OX1 3TA UK
| | - Michael C. Willis
- Chemistry Research Laboratory Oxford University 12 Mansfield Road Oxford OX1 3TA UK
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6
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Budiman YP, Jayaraman A, Friedrich A, Kerner F, Radius U, Marder TB. Palladium-Catalyzed Homocoupling of Highly Fluorinated Arylboronates: Studies of the Influence of Strongly vs Weakly Coordinating Solvents on the Reductive Elimination Process. J Am Chem Soc 2020; 142:6036-6050. [PMID: 32134642 DOI: 10.1021/jacs.9b11871] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
C-C reductive elimination from [PdL2(C6F5)2] to form polyfluorinated biaryls has been a challenge for over 50 years. Thus, palladium-catalyzed homocoupling of arylboronates (ArF-Bpin) containing two ortho-fluorine substituents is very difficult, as the reaction typically stops at the [PdL2(ArF)2] stage after two transmetalation steps. The transmetalated complexes cis-[Pd(MeCN)2(C6F5)2] (3a), cis-[Pd(MeCN)2(2,4,6-C6F3H2)2] (3b), and cis-[Pd(MeCN)2(2,6-C6F2H3)2] (3e) have been isolated from the reaction of ArF-Bpin with Pd(OAc)2 in acetonitrile solvent, with no homocoupling observed. However, catalytic homocoupling proceeds smoothly in a "weakly coordinating" arene solvent as long as no ancillary ligands or coordinating solvents are present. DFT computations reveal that the active catalyst formed by arene solvent coordination leads to an overall reduced barrier for the reductive elimination step compared to the formation of stable [PdL2(ArF)2] complexes in the presence of a donor ligand or solvent L.
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Affiliation(s)
- Yudha P Budiman
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, 45363 Jatinangor, Indonesia
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7
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Li S, Li WJ, Yang X, Sun R, Tang J, Zheng XL, Yuan ML, Li RX, Chen H, Fu HY. Selective direct C–H polyfluoroarylation of electron-deficient N-heterocyclic compounds. Org Chem Front 2020. [DOI: 10.1039/d0qo00923g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An efficient protocol of C2-selective direct C–H polyfluoroarylation of six-membered N-heterocyclic compounds with polyfluorobenzoic acid via corresponding N-methyl quaternary ammonium salts.
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8
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Mutoh Y, Yamamoto K, Saito S. Suzuki–Miyaura Cross-Coupling of 1,8-Diaminonaphthalene (dan)-Protected Arylboronic Acids. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03667] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuichiro Mutoh
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka,
Shinjuku-ku, Tokyo 162-8601, Japan
| | - Kensuke Yamamoto
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka,
Shinjuku-ku, Tokyo 162-8601, Japan
| | - Shinichi Saito
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka,
Shinjuku-ku, Tokyo 162-8601, Japan
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9
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Budiman YP, Friedrich A, Radius U, Marder TB. Copper‐Catalysed Suzuki‐Miyaura Cross‐Coupling of Highly Fluorinated Aryl Boronate Esters with Aryl Iodides and Bromides and Fluoroarene−Arene π‐Stacking Interactions in the Products. ChemCatChem 2019. [DOI: 10.1002/cctc.201901220] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yudha P. Budiman
- Institut für Anorganische Chemie, and Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Würzburg 97074 Germany
- Department of ChemistryFaculty of Mathematics and Natural SciencesUniversitas Padjadjaran Jatinangor 45363 Indonesia
| | - Alexandra Friedrich
- Institut für Anorganische Chemie, and Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Würzburg 97074 Germany
| | - Udo Radius
- Institut für Anorganische Chemie, and Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Würzburg 97074 Germany
| | - Todd B. Marder
- Institut für Anorganische Chemie, and Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Würzburg 97074 Germany
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10
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Karroum NB, Patinote C, Deleuze-Masquéfa C, Moarbess G, Diab-Assaf M, Cuq P, Kassab I, Bonnet PA. Methylation of imidazopyrazine, imidazoquinoxaline, and pyrazoloquinoxaline through Suzuki–Miyaura cross coupling. Chem Heterocycl Compd (N Y) 2018. [DOI: 10.1007/s10593-018-2252-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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11
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Kohlmann J, Braun T, Laubenstein R, Herrmann R. Suzuki-Miyaura Cross-Coupling Reactions of Highly Fluorinated Arylboronic Esters: Catalytic Studies and Stoichiometric Model Reactions on the Transmetallation Step. Chemistry 2017; 23:12218-12232. [DOI: 10.1002/chem.201700549] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Johannes Kohlmann
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Thomas Braun
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Reik Laubenstein
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Roy Herrmann
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Straße 2 12489 Berlin Germany
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12
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Cox PA, Leach AG, Campbell AD, Lloyd-Jones GC. Protodeboronation of Heteroaromatic, Vinyl, and Cyclopropyl Boronic Acids: pH–Rate Profiles, Autocatalysis, and Disproportionation. J Am Chem Soc 2016; 138:9145-57. [DOI: 10.1021/jacs.6b03283] [Citation(s) in RCA: 218] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Paul A. Cox
- School
of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster
Road, Edinburgh EH9 3FJ, United Kingdom
| | - Andrew G. Leach
- School
of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, United Kingdom
| | - Andrew D. Campbell
- Pharmaceutical
Technology and Development, AstraZeneca, Silk Road Business Park, Macclesfield SK10 2NA, United Kingdom
| | - Guy C. Lloyd-Jones
- School
of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster
Road, Edinburgh EH9 3FJ, United Kingdom
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13
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Hommes P, Reissig HU. Synthesis and Photophysical Properties of Substituted 2,2′:6′,2′′-Terpyridine Derivatives and Analogous Compounds with a Central Thiophene Ring. ASIAN J ORG CHEM 2016. [DOI: 10.1002/ajoc.201600215] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Paul Hommes
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustrasse 3 14195 Berlin Germany
| | - Hans-Ulrich Reissig
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustrasse 3 14195 Berlin Germany
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14
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Bardin VV, Shabalin AY, Adonin NY. Weakly nucleophilic potassium aryltrifluoroborates in palladium-catalyzed Suzuki-Miyaura reactions: relative reactivity of K[4-RC6F4BF3] and the role of silver-assistance in acceleration of transmetallation. Beilstein J Org Chem 2015; 11:608-16. [PMID: 26124862 PMCID: PMC4464464 DOI: 10.3762/bjoc.11.68] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/09/2015] [Indexed: 11/30/2022] Open
Abstract
Small differences in the reactivity of weakly nucleophilic potassium aryltrifluoroborates are revealed in the silver-assisted Pd-catalyzed cross-coupling of K[4-RC6F4BF3] (R = H, Bu, MeO, EtO, PrO, iPrO, BuO, t-BuO, CH2=CHCH2O, PhCH2O, PhCH2CH2O, PhO, F, pyrazol-1-yl, pyrrol-1-yl, and indol-1-yl) with ArX (4-BrC6H4CH3, 4-IC6H4F and 3-IC6H4F). An assumed role of silver(I) compounds AgmY (Y = O, NO3, SO4, BF4, F) consists in polarization of the Pd–X bond in neutral complex ArPdLnX with the generation of the related transition state or formation of [ArPdLn][XAgmY] with a highly electrophilic cation and subsequent transmetallation with the weakly nucleophilic borate. Efficiency of AgmY as a polarizing agent decreases in order Ag2O > AgNO3 ≈ Ag2SO4 > Ag[BF4] > AgF. No clear correlation between the reactivity of K[4-RC6F4BF3] and substituent electron parameters, σI and σR°, of the aryl group 4-RC6F4 was found.
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Affiliation(s)
- Vadim V Bardin
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, SB RAS, Acad. Lavrentjev Ave. 9, Novosibirsk, 630090, Russian Federation ; Novosibirsk State University, Pirogova str., 2, Novosibirsk, 630090, Russian Federation
| | - Anton Yu Shabalin
- G.K. Boreskov Institute of Catalysis, SB RAS, Acad. Lavrentjev Ave. 5, Novosibirsk, 630090, Russian Federation
| | - Nicolay Yu Adonin
- Novosibirsk State University, Pirogova str., 2, Novosibirsk, 630090, Russian Federation ; G.K. Boreskov Institute of Catalysis, SB RAS, Acad. Lavrentjev Ave. 5, Novosibirsk, 630090, Russian Federation
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15
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Conelly-Espinosa P, Toscano RA, Morales-Morales D. Synthesis and characterization of hydrophilic theophylline base compounds and their use as ligands in the microwave assisted Suzuki–Miyaura couplings of halopyridines in water. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.08.103] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Shabalin AY, Adonin NY, Bardin VV, Parmon VN. The influence of the nature of phosphine ligand on palladium catalysts for cross-coupling of weakly nucleophilic potassium pentafluorophenyltrifluoroborate with ArHal and PhCH2Hal (Hal=Br, Cl). Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.04.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Lennox AJJ, Lloyd-Jones GC. Selection of boron reagents for Suzuki–Miyaura coupling. Chem Soc Rev 2014; 43:412-43. [DOI: 10.1039/c3cs60197h] [Citation(s) in RCA: 926] [Impact Index Per Article: 92.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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18
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Lentijo S, Aullón G, Miguel JA, Espinet P. Highly fluorescent complexes with gold, palladium or platinum linked to perylene through a tetrafluorophenyl group. Dalton Trans 2013; 42:6353-65. [DOI: 10.1039/c3dt32843k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Abstract
A procedure for benzylic Suzuki-Miyaura cross-coupling under microwave conditions has been developed. These conditions allowed for heterocyclic compounds to be coupled. Optimum conditions found were Pd(OAc)(2), JohnPhos as the catalyst and ligand, potassium carbonate as base, and DMF as the solvent. Using these conditions, a library of structurally diverse compounds was synthesized.
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Fan S, Yang J, Zhang X. Pd-catalyzed direct cross-coupling of electron-deficient polyfluoroarenes with heteroaromatic tosylates. Org Lett 2011; 13:4374-7. [PMID: 21774509 DOI: 10.1021/ol201706t] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report a Pd-catalyzed direct cross-coupling of electron-deficient polyfluoroarenes with heteroaromatic tosylates. The notable features of this reaction are its high reaction efficiency, excellent chemoselectivity, operational simplicity, and mild reaction conditions. We have applied this protocol to prepare the semiconducting materials in a highly efficient manner.
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Affiliation(s)
- Shilu Fan
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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21
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Keyes L, Sun AD, Love JA. Exploration of the Scope of Pt-Catalyzed C-F Activation. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100478] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Kinzel T, Zhang Y, Buchwald SL. A new palladium precatalyst allows for the fast Suzuki-Miyaura coupling reactions of unstable polyfluorophenyl and 2-heteroaryl boronic acids. J Am Chem Soc 2011; 132:14073-5. [PMID: 20858009 DOI: 10.1021/ja1073799] [Citation(s) in RCA: 490] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Boronic acids which quickly deboronate under basic conditions, such as polyfluorophenylboronic acid and five-membered 2-heteroaromatic boronic acids, are especially challenging coupling partners for Suzuki-Miyaura reactions. Nevertheless, being able to use these substrates is highly desirable for a number of applications. Having found that monodentate biarylphosphine ligands can promote these coupling processes, we developed a precatalyst that forms the catalytically active species under conditions where boronic acid decomposition is slow. With this precatalyst, Suzuki-Miyaura reactions of a wide range of (hetero)aryl chlorides, bromides, and triflates with polyfluorophenyl, 2-furan, 2-thiophene, and 2-pyrroleboronic acids and their analogues proceed at room temperature or 40 °C in short reaction times to give the desired products in excellent yields.
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Affiliation(s)
- Tom Kinzel
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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23
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Hassan Omar O, Babudri F, Farinola GM, Naso F, Operamolla A, Pedone A. Synthesis of d-glucose and l-phenylalanine substituted phenylene–thiophene oligomers. Tetrahedron 2011. [DOI: 10.1016/j.tet.2010.11.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Poudel PP, Chen J, Cammers A. Intramolecular π-Stacking in Isostructural Conformational Probes Depends Strongly on Charge Separation, a Proton NMR Study. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800663] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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26
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Pinheiro EDS, Antunes OAC, Fortunak JMD. A survey of the syntheses of active pharmaceutical ingredients for antiretroviral drug combinations critical to access in emerging nations. Antiviral Res 2008; 79:143-65. [PMID: 18571246 DOI: 10.1016/j.antiviral.2008.05.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2006] [Revised: 04/17/2008] [Accepted: 05/05/2008] [Indexed: 11/24/2022]
Abstract
It has been roughly 25 years since the threat posed by human immunodeficiency virus type 1 (HIV-1) became widely known. The cumulative death toll from HIV/AIDS is now greater than 25 million. There are approximately 33 million people living worldwide with this disease, of whom about 68% (22.5 million) live in sub-Saharan Africa (http://www.avert.org/worldstats.htm). A number of antiretroviral (ARV) drugs have been approved for treatment of HIV/AIDS. Inhibitors of HIV reverse transcriptase (RTIs) include the nucleoside/nucleotide drugs zidovudine, lamivudine, abacavir, didanosine, stavudine, emtricitabine and tenofovir disoproxil fumarate. Non-nucleoside RTIs include nevirapine, efavirenz and etravirine. Inhibitors of HIV protease (PIs) include saquinavir, ritonavir, lopinavir, nelfinavir, indinavir, fosamprenavir and atazanavir. Enfuvirtide inhibits the HIV fusion protein. The CCR5 chemokine antagonist maraviroc and the integrase inhibitor raltegravir were very recently approved by the US FDA. Fixed-dose combinations (FDCs) have been formulated to increase tolerability, convenience and compliance. First-line drug combinations are offered to treatment-naive patients, while second-line drugs are reserved for those who no longer respond adequately to first-line therapy. In developing countries a modest but increasing fraction of those infected have access to ARVs. The Clinton HIV/AIDS Initiative estimates that 2.4 million of the nearly 8 million individuals needing treatment in developing nations have access to some drugs. First-line FDCs used in resource-poor settings are largely combinations of two nucleoside RTIs and a non-nucleoside RTI or PI. The effectiveness of these combinations decreases over time, requiring a switch to combinations that retain potency in the presence of viral resistance. Increasing access to second-line FDCs and new developments in first-line ARV therapy are cost challenges. In high-income countries the cost of ARV therapy is largely irrelevant, except for "advanced salvage" drugs such as enfuvirtide. In resource-poor settings cost is a huge factor that limits drug access, resulting in high rates of new infection and subsequent mortality. IP coverage, where granted, can keep access prices for essential ARVs higher than would otherwise be the case. Large, innovator companies have made drugs available at prices very close to the cost of manufacturing for "lowest income" countries. Generic providers in India and elsewhere provide the largest supply of drugs for the developing world. The recent issuance of Voluntary and Compulsory Licenses (VLs, CLs) through the World Trade Organization's TRIP (Treaty Respecting Intellectual Property) provisions arguably contribute to bringing down access prices. The utilization of improved science, pooled purchasing and intelligent procurement practices all definitely contribute to access. This work surveys the production processes for several critical ARVs. These are discussed in terms of scale up, raw material/intermediates and active pharmaceutical ingredient (API) costs. In some cases new routes to APIs or critical intermediates are needed. Based on potential new chemistries, there are significant opportunities to reduce cost for a number of critical ARVs.
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Affiliation(s)
- Eloan Dos Santos Pinheiro
- Instituto de Química, UFRJ, CT Bloco A, Lab 641, Cidade Universitária, Rio de Janeiro, RJ 21945-970, Brazil.
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Koizumi TA, Yamazaki A, Yamamoto T. Reductive elimination of C6F5–C6F5 in the reaction of bis(pentafluorophenyl)palladium(ii) complexes with protic acids. Dalton Trans 2008:3949-52. [DOI: 10.1039/b802408a] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Shi Z, Li B, Wan X, Cheng J, Fang Z, Cao B, Qin C, Wang Y. Suzuki–Miyaura Coupling Reaction by PdII-Catalyzed Aromatic CH Bond Activation Directed by anN-Alkyl Acetamino Group. Angew Chem Int Ed Engl 2007. [DOI: 10.1002/ange.200700590] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Shi Z, Li B, Wan X, Cheng J, Fang Z, Cao B, Qin C, Wang Y. Suzuki–Miyaura Coupling Reaction by PdII-Catalyzed Aromatic CH Bond Activation Directed by anN-Alkyl Acetamino Group. Angew Chem Int Ed Engl 2007; 46:5554-8. [PMID: 17579890 DOI: 10.1002/anie.200700590] [Citation(s) in RCA: 270] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Zhangjie Shi
- Beijing National Laboratory of Molecular Sciences (BNLMS) [corrected] China.
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Korenaga T, Kosaki T, Fukumura R, Ema T, Sakai T. Suzuki−Miyaura Coupling Reaction Using Pentafluorophenylboronic Acid. Org Lett 2005; 7:4915-7. [PMID: 16235921 DOI: 10.1021/ol051866i] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] We have found new conditions for the Suzuki-Miyaura coupling reaction applicable to pentafluorophenylboronic acid (C(6)F(5)B(OH)(2)) (1), which is an inactive substrate under normal conditions. The reactions of 1 with phenyl iodide or bromide under Pd(PPh(3))(4)/CsF/Ag(2)O or Pd(2)(dba)(3)/P(t-Bu)(3)/CsF/Ag(2)O catalytic system conditions gave 2,3,4,5,6-pentafluoro-1,1'-biphenyl (3a) in more than 90% yields. Combination of CsF and Ag(2)O was essential for promoting these reactions.
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Affiliation(s)
- Toshinobu Korenaga
- Department of Synthetic Chemistry, Graduate School of Natural Science and Technology, Okayama University, Japan.
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Chapter 6.1 Six-membered ring systems: Pyridines and benzo derivatives. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0959-6380(05)80054-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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