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Kirinda VC, Vemuri GN, Kress NG, Flynn KM, Kumarage ND, Schrage BR, Tierney DL, Ziegler CJ, Hartley CS. Fluorine Labeling of ortho-Phenylenes to Facilitate Conformational Analysis. J Org Chem 2021; 86:15085-15095. [PMID: 34641678 DOI: 10.1021/acs.joc.1c01770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1H NMR spectroscopy is a powerful tool for the conformational analysis of ortho-phenylene foldamers in solution. However, as o-phenylenes are integrated into ever more complex systems, we are reaching the limits of what can be analyzed by 1H- and 13C-based NMR techniques. Here, we explore fluorine labeling of o-phenylene oligomers for analysis by 19F NMR spectroscopy. Two series of fluorinated oligomers have been synthesized. Optimization of monomers for Suzuki coupling enables an efficient stepwise oligomer synthesis. The oligomers all adopt well-folded geometries in solution, as determined by 1H NMR spectroscopy and X-ray crystallography. 19F NMR experiments complement these methods well. The resolved singlets of one-dimensional 19F{1H} spectra are very useful for determining relative conformer populations. The additional information from two-dimensional 19F NMR spectra is also clearly valuable when making 1H assignments. The comparison of 19F isotropic shielding predictions to experimental chemical shifts is not, however, currently sufficient by itself to establish o-phenylene geometries.
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Affiliation(s)
- Viraj C Kirinda
- Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Gopi Nath Vemuri
- Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Nicholas G Kress
- Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Kaitlyn M Flynn
- Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | | | - Briana R Schrage
- Department of Chemistry, University of Akron, Akron, Ohio 44325, United States
| | - David L Tierney
- Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | | | - C Scott Hartley
- Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States
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Abstract
AbstractOrganofluorine compounds have gained interest in the fields of pharmaceuticals, agrochemicals, diagnostics, materials, and catalysis. Suzuki–Miyaura coupling reactions of fluorinated arenes made a tremendous impact in chemical and biological research and made organofluorinated molecules more readily available. This review gives a brief summary of Suzuki–Miyaura coupling reactions of fluorinated benzene derivatives. In this context, various aspects, such as regioselectivity, efficiency, and applications, are discussed.1 Introduction2 Organofluorine Compounds3 Suzuki–Miyaura Reactions of Fluorohalobenzenes3.1 Fluorophthalates3.2 Reactions of Pentafluorohalobenzenes3.3 Tetrafluorohalobenzenes3.4 Trifluorohalobenzenes3.5 Difluorohalobenzenes3.6 Monofluorohalobenzenes3.7 Halo(trifluoromethyl)benzenes3.8 Trifluoromethyl Pyridines4 S Summary
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Affiliation(s)
- Peter Langer
- Institut für Chemie, Universität Rostock
- Leibniz-Institut für Katalyse an der Universität Rostock e. V
| | - Shoaib Iqbal
- Institut für Chemie, Universität Rostock
- Leibniz-Institut für Katalyse an der Universität Rostock e. V
- Department of Chemistry, COMSATS Institute of Information Technology
| | - Muhammad Sharif
- Institut für Chemie, Universität Rostock
- Leibniz-Institut für Katalyse an der Universität Rostock e. V
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Synthesis of Pharmacologically Relevant New Derivatives of Maleimides via Ligand-Free Pd-Catalyzed Suzuki–Miyaura Cross-Coupling Reactions. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2020. [DOI: 10.1007/s13369-020-04450-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Bulfield D, Huber SM. Synthesis of Polyflourinated Biphenyls; Pushing the Boundaries of Suzuki-Miyaura Cross Coupling with Electron-Poor Substrates. J Org Chem 2017; 82:13188-13203. [PMID: 29156885 PMCID: PMC5746848 DOI: 10.1021/acs.joc.7b02267] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
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Polyfluorinated biphenyls
are interesting and promising substrates
for many different applications. Unfortunately, all current methods
for the syntheses of these compounds only work for a hand full of
molecules or only in very special cases. Thus, many of these compounds
are still inaccessible to date. Here we report a general strategy
for the synthesis of a wide range of highly fluorinated biphenyls.
In our studies we investigated crucial parameters, such as different
phosphine ligands and the influence of various nucleophiles and electrophiles
with different degrees of fluorination. These results extend the scope
of the already very versatile Suzuki–Miyaura reaction toward
the synthesis of very electron-poor products, making these more readily
accessible. The presented methodology is scalable and versatile without
the need for elaborate phosphine ligands or Pd-precatalysts.
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Affiliation(s)
- David Bulfield
- Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum , Universitätsstraße 150, 44801 Bochum, Germany
| | - Stefan M Huber
- Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum , Universitätsstraße 150, 44801 Bochum, Germany
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Synthesis of functionalised fluorinated pyridine derivatives by site-selective Suzuki-Miyaura cross-coupling reactions of halogenated pyridines. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2017. [DOI: 10.1515/znb-2016-0213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The Suzuki-Miyaura reaction of 2,6-dichloro-3-(trifluoromethyl)pyridine with 1 equiv of arylboronic acids resulted in site-selective formation of 2-aryl-6-chloro-3-(trifluoromethyl)pyridine. Due to electronic reasons, the reaction takes place at the sterically more hindered position. The selectivity was rationalised by DFT calculations. The one-pot reaction with two different arylboronic acids afforded 2,6-diaryl-3-(trifluoromethyl)pyridine containing two different aryl substituents. The reactions proceeded smoothly in the absence of phosphine ligands. In addition, Suzuki-Miyaura reactions of 2,6-dichloro-4-(trifluoromethyl)pyridine with one or two equivalents of arylboronic acids were carried out.
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Gu N, Liu Y, Liu P, Ma X, Yan L, Dai B. Synthesis of Terphenyl Derivatives by Pd-Catalyzed Suzuki-Miyaura Reaction of Dibromobenzene Using 2N2O-Salen as a Ligand in Aqueous Solution. CHINESE J CHEM 2015. [DOI: 10.1002/cjoc.201500446] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Al-Zoubi RM, Al-Jammal WK, El-Khateeb MY, McDonald R. Synthesis of Diiodinated Biphenyls and Iodinatedmeta-Terphenyls by Regioselective Suzuki-Miyaura Cross-Coupling Reactions of 5-Substituted 1,2,3-Triiodobenzenes. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500263] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Zhao P, Young MD, Beaudry CM. Regioselective Suzuki couplings of non-symmetric dibromobenzenes: alkenes as regiochemical control elements. Org Biomol Chem 2015; 13:6162-5. [DOI: 10.1039/c5ob00717h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The regioselective Suzuki coupling of dibromobenzenes has been investigated. The regiochemistry is high when one bromine atom is proximal to an alkene.
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Albéniz AC, Casares JA. Palladium-Mediated Organofluorine Chemistry. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2014. [DOI: 10.1016/b978-0-12-800976-5.00001-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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