1
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Weick F, Hagmeyer N, Giraud M, Dietzek-Ivanšić B, Wagenknecht HA. Reductive Activation of Aryl Chlorides by Tuning the Radical Cation Properties of N-Phenylphenothiazines as Organophotoredox Catalysts. Chemistry 2023; 29:e202302347. [PMID: 37589486 DOI: 10.1002/chem.202302347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 08/17/2023] [Accepted: 08/17/2023] [Indexed: 08/18/2023]
Abstract
Aryl chlorides as substrates for arylations present a particular challenge for photoredox catalytic activation due to their strong C(sp2 )-Cl bond and their strong reduction potential. Electron-rich N-phenylphenothiazines, as organophotoredox catalysts, are capable of cleaving aryl chlorides simply by photoinduced electron transfer without the need for an additional electrochemical activation setup or any other advanced photocatalysis technique. Due to the extremely strong reduction potential in the excited state of the N-phenylphenothiazines the substrate scope is high and includes aryl chlorides both with electron-withdrawing and electron-donating substituents. We evidence this reactivity for photocatalytic borylations and phosphonylations. Advanced time-resolved transient absorption spectroscopy in combination with electrochemistry was the key to elucidating and comparing the unusual photophysical properties not only of the N-phenylphenothiazines, but also of their cation radicals as the central intermediates in the photocatalytic cycle. The revealed photophysics allowed the excited-state and radical-cation properties to be fine-tuned by the molecular design of the N-phenylphenothiazines; this improved the photocatalytic activity.
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Affiliation(s)
- Fabian Weick
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany
| | - Nina Hagmeyer
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Lessingstraße 4, 07743, Jena, Germany
| | - Madeleine Giraud
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany
| | - Benjamin Dietzek-Ivanšić
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Lessingstraße 4, 07743, Jena, Germany
- Research Department Functional Interfaces, Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Hans-Achim Wagenknecht
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany
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2
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Yasuo E, Aikawa K, Nozaki K, Okazoe T. Fluoroalkylated hypervalent sulfur fluorides: radical addition of arylchlorotetrafluoro-λ 6-sulfanes to tetrafluoroethylene. Chem Sci 2023; 14:12379-12385. [PMID: 37969576 PMCID: PMC10631236 DOI: 10.1039/d3sc04837c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 10/18/2023] [Indexed: 11/17/2023] Open
Abstract
Fluorinated groups are essential hydrophobic groups in drug design. Combining a carbon-free tetrafluoro-λ6-sulfanyl (SF4) group with a polyfluoroalkyl group (RF) provides SF4RF groups, exhibiting high hydrophobicity with a short carbon chain. In this study, various aryltetrafluoro(polyfluoroalkyl)-λ6-sulfanes (ArSF4RF) were synthesized through the radical addition of arylchlorotetrafluoro-λ6-sulfanes (ArSF4Cl) to tetrafluoroethylene. In addition, quantification of hydrophobic constants (πPh) indicated that the SF4 group is considerably more hydrophobic than a difluoromethylene (CF2) group. Further transformation reactions revealed the stabilities and reactivities of these novel fluorinated groups. The high hydrophobicity and synthetic utility of the SF4RF group lead to the potential applications of the SF4RF group in the pharmaceutical field.
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Affiliation(s)
- Eisuke Yasuo
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 2-11-16 Yayoi Bunkyo-ku Tokyo 113-0032 Japan
| | - Kohsuke Aikawa
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 2-11-16 Yayoi Bunkyo-ku Tokyo 113-0032 Japan
| | - Kyoko Nozaki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-8656 Japan
| | - Takashi Okazoe
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 2-11-16 Yayoi Bunkyo-ku Tokyo 113-0032 Japan
- Yokohama Technical Center, AGC Inc. 1-1 Suehiro-cho Tsurumi-ku Yokohama 230-0045 Japan
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3
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Sindhe H, Saiyed N, Kamble A, Mounika Reddy M, Singh A, Sharma S. Catalytic and Chemodivergent Synthesis of 1-Substituted 9 H-Pyrrolo[1,2- a]indoles via Annulation of β-CF 3 Enones with 3-Substituted Indoles. J Org Chem 2023; 88:230-244. [PMID: 36503232 DOI: 10.1021/acs.joc.2c02240] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chemodivergent reactions are more advantageous in organic synthesis that yield diversely functionalized scaffolds from common starting materials. Herein, we report an efficient metal-free chemodivergent protocol for the synthesis of 1-substituted 9H-pyrrolo[1,2-a]indole derivatives in the presence of catalytic amounts of Lewis acid/Brønsted acid conditions using 3-substituted indoles and β-trifluoromethyl-α,β-unsaturated ketones. Fine-tuning of the catalyst and solvent system in the reaction conditions deliver the trifluoromethyl, trifluoroethylcarboxylate, or carboxylic acid substituents on the C1-position of 9H-pyrrolo[1,2-a]indole derivatives in situ. It is postulated that the solvent and LA/BA catalyst interaction was found to be crucial for the catalytic C-F activation in these transformations.
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Affiliation(s)
- Haritha Sindhe
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Nehanaz Saiyed
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Akshay Kamble
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Malladi Mounika Reddy
- Department of Natural Products, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Amardeep Singh
- Department of Natural Products, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat 382355, India
| | - Satyasheel Sharma
- Department of Natural Products, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat 382355, India
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4
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Herrera D, Peral D, Bayón JC. Preparation of carboxylic arylphosphines by hydrolysis of the trifluoromethyl group. RSC Adv 2022; 12:7103-7114. [PMID: 35424709 PMCID: PMC8982155 DOI: 10.1039/d2ra00420h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/24/2022] [Indexed: 11/21/2022] Open
Abstract
Triarylphosphines substituted with carboxylic and trifluoromethlyl groups have been prepared by the hydrolysis of trifluoromethyl groups using fuming sulfuric acid and boric acid. The reaction has been studied in a set of homoleptic and heteroleptic trifluoromethylated triarylphosphines and offers a new synthetic procedure for the preparation of carboxylic phosphines with a relatively simple methodology. The degree of carboxylation is modulated by the reaction conditions and is sensitive to the substitution pattern of the starting trifluoromethylated phosphines. A pH-dependent procedure based on the amphiphilic character of these phosphines was developed for their separation and purification. The electronic properties of the synthesized carboxylic-trifluoromethylated phosphines have been analyzed by 31P NMR of the corresponding selenide derivatives. Finally, the structures of two palladium complexes, containing the para and meta carboxylic-trifluoromethylated phosphines are also described, showing different dimeric structures.
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Affiliation(s)
- Daniel Herrera
- Department of Chemistry, Universitat Autònoma de Barcelona 08193 Cerdanyola del Vallés Spain
| | - Daniel Peral
- Department of Chemistry, Universitat Autònoma de Barcelona 08193 Cerdanyola del Vallés Spain
| | - J Carles Bayón
- Department of Chemistry, Universitat Autònoma de Barcelona 08193 Cerdanyola del Vallés Spain
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5
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Fuchibe K, Ichikawa J, Takao G, Hakozaki T, Miura K, Urushibara Y. Construction of Substituted [4]Acene Frameworks Based on Double Cationic Cyclizations of Fluoroalkenes. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/s-0037-1610791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractIn this study, 5-substituted and 5,6-disubstituted [4]acenes were synthesized by the double cationic cyclization of fluoroalkenes. (a) After being treated with Me2AlCl (1.2 equiv), 2-trifluoromethyl-1-alkenes bearing two aryl groups underwent domino Friedel–Crafts-type cyclization (two-ring construction) followed by dehydrogenation to generate 5-fluorinated [4]acenes. The same (trifluoromethyl)alkenes were treated with both Me2AlCl (1.2 equiv) and Me3Al (1.0 equiv), resulting in selective one-ring construction and the creation of bicyclic 1,1-difluoro-1-alkenes. (b) When treated with triflic acid, the bicyclic difluoroalkenes underwent regioselective protonation to generate CF2 cations; Friedel–Crafts-type cyclization of these cations provided tetracyclic ketones. The obtained ketones act as an appropriate platform for the introduction of substituents at the 5-position of [4]acenes. (c) When treated with DDQ/H+, the bicyclic difluoroalkenes underwent oxidative generation of allylic CF2 cations; Friedel–Crafts-type cyclization of these cations produced tetracyclic enones. The enones were subjected to double addition of carbanions to facilitate the introduction of two substituents at the 5- and 6-positions of dihydro[4]acenes.
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6
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Yu H, Zhang Z, Zhang X, Xu Y, Huo D, Zhang L, Wang W. Green Tandem [5C + 1C] Cycloaromatization of α-Alkenoyl Ketene Dithioacetals and Nitroethane in Water: Eco-Friendly Synthesis of Ortho-Acylphenols. J Org Chem 2022; 87:2985-2996. [PMID: 35132856 DOI: 10.1021/acs.joc.1c02825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
For the first time, an eco-friendly and sustainable tandem [5C + 1C] cycloaromatization of α-alkenoyl ketene dithioacetals and nitroethane in water for the efficient synthesis of ortho-acylphenols was reported. In refluxing water, a range of α-alkenoyl ketene dithioacetals and nitroethane smoothly underwent tandem Michael addition/cyclization/aromatization reactions in the presence of 2.0 equivalents of DBU to provide various ortho-acylphenols in excellent yields. The green approach to ortho-acylphenols not only avoided the use of harmful organic solvents, which could result in serious environmental and safety issues, but also exhibited fascinating features such as good substrate scope, excellent yields, simple purification for desired products, ease of scale-up, and reusable aqueous medium.
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Affiliation(s)
- Haifeng Yu
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
| | - Zheyu Zhang
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
| | - Xue Zhang
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
| | - Yupeng Xu
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
| | - Dongyue Huo
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
| | - Lanyun Zhang
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
| | - Wenju Wang
- College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
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7
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A new and efficient approach to 2-hydroxybenzophenone derivatives via [5C + 1C] annulation of α-alkenoyl-α-aroyl ketene dithioacetals and nitroalkanes. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132427] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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8
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Hermannsdorfer A, Driess M. Silicon Tetrakis(trifluoromethanesulfonate): A Simple Neutral Silane Acting as a Soft and Hard Lewis Superacid. Angew Chem Int Ed Engl 2021; 60:13656-13660. [PMID: 33826216 PMCID: PMC8252640 DOI: 10.1002/anie.202103414] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/01/2021] [Indexed: 11/10/2022]
Abstract
A facile synthesis and isolation of pristine silicon tetrakis(trifluoromethanesulfonate), Si(OTf)4, is reported, acting as the first neutral silicon‐based Lewis superacid suitable towards soft and hard Lewis bases. Its OTf groups have a dual function: they are excellent leaving groups and modulate the degree of reactivity towards soft and hard Lewis bases. Exposed to soft Lewis donors, Si(OTf)4 leads to [L2Si(OTf)4] complexes (L=isocyanide, thioether and carbonyl compounds) with retention of all Si−OTf bonds. In contrast, it can cleave C−X bonds (X=F, Cl) of hard organic Lewis bases with a high tendency to form SiX4 (X=F, Cl) after halide/triflate exchange. Most notable, Si(OTf)4 allows a gentle oxydefluorination of mono‐ and bis(trifluoromethyl)benzenes, resulting in the formation of the corresponding benzoylium species, which are stabilized by the weakly coordinating [Si(OTf)6] dianion.
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Affiliation(s)
- André Hermannsdorfer
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin, Strasse des 17. Juni 115, Sekr. C2, 10623, Berlin, Germany
| | - Matthias Driess
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin, Strasse des 17. Juni 115, Sekr. C2, 10623, Berlin, Germany
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9
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Hermannsdorfer A, Driess M. Siliciumtetrakis(trifluormethansulfonat): Ein einfaches, neutrales Silan als weiche und harte Lewis‐Supersäure. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- André Hermannsdorfer
- Institut für Chemie, Metallorganische Chemie und anorganische Materialien Technische Universität Berlin Straße des 17. Juni 115, Sekr. C2 10623 Berlin Deutschland
| | - Matthias Driess
- Institut für Chemie, Metallorganische Chemie und anorganische Materialien Technische Universität Berlin Straße des 17. Juni 115, Sekr. C2 10623 Berlin Deutschland
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10
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Murray BJ, Boulton LT, Sandford G. HFO-1234yf as a CF3-building block: Synthesis of trifluoromethyl-benzophenone derivatives by deoxygenative aromatisation. J Fluor Chem 2021. [DOI: 10.1016/j.jfluchem.2021.109774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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11
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Yan G, Qiu K, Guo M. Recent advance in the C–F bond functionalization of trifluoromethyl-containing compounds. Org Chem Front 2021. [DOI: 10.1039/d1qo00037c] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The C–F bond is the strongest single bond in organic compounds.
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Affiliation(s)
- Guobing Yan
- College of Jiyang
- Zhejiang A&F University
- Zhuji 311800
- China
- College of Science
| | - Kaiying Qiu
- Department of Chemistry
- Lishui University
- Lishui 323000
- China
| | - Ming Guo
- College of Jiyang
- Zhejiang A&F University
- Zhuji 311800
- China
- College of Science
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12
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Parida R, Nambiar SR, Reddy GN, Giri S. Designing aromatic heterocyclic superacids in terms of Brønsted and Lewis perspectives. Phys Chem Chem Phys 2020; 22:1923-1931. [PMID: 31912831 DOI: 10.1039/c9cp06054e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The unexplored area of organic superacids was investigated in terms of both Brønsted and Lewis concepts of acids and bases. The primary requirement of a superacid-high affinity for electron/fluoride ions was fulfilled using two strategies: (i) using the superhalogen-type heterocyclic framework and (ii) selecting systems that have an electron count one short of attaining (4n + 2) Hückel aromaticity. With these in mind, eleven systems were considered throughout the study, expected to cross the target of 100% H2SO4 acidity and/or the fluoride affinity of SbF5. To enhance the pKa and F- affinity values of the considered systems, electron-withdrawing ligands F and CN were employed. The superhalogen and aromaticity properties were verified by vertical detachment energy (VDE) and nucleus independent chemical shift (NICS) calculations, respectively. Finally, the collective effect of the potential super Lewis acids was looked into using a BL3 skeleton with them acting as ligands.
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Affiliation(s)
- Rakesh Parida
- School of Applied Sciences and Humanities, Haldia Institute of Technology, Haldia, 721657, India. and Department of Chemistry, National Institute of Technology Rourkela, Odisha 769008, India
| | - Sachin Ramesh Nambiar
- Department of Chemistry, National Institute of Technology Rourkela, Odisha 769008, India
| | - G Naaresh Reddy
- School of Applied Sciences and Humanities, Haldia Institute of Technology, Haldia, 721657, India. and Department of Chemistry, National Institute of Technology Rourkela, Odisha 769008, India
| | - Santanab Giri
- School of Applied Sciences and Humanities, Haldia Institute of Technology, Haldia, 721657, India.
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13
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Leszczyński P, Budniak A, Grzeszkiewicz M, Gawraczyński J, Dobrzycki Ł, Malinowski P, Jaroń T, Cyrański M, Szarek P, Mazej Z, Grochala W. Insights into reactivity patterns of Ag(II)SO4 with respect to fluoro- and trifluoromethyl-substituted aromatics. J Fluor Chem 2019. [DOI: 10.1016/j.jfluchem.2018.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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14
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Yang X, Tsui GC. Copper-mediated 1,2-bis(trifluoromethylation) of arynes. Chem Sci 2018; 9:8871-8875. [PMID: 30627405 PMCID: PMC6296300 DOI: 10.1039/c8sc03754j] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 09/20/2018] [Indexed: 01/31/2023] Open
Abstract
We herein describe an unprecedented 1,2-bis(trifluoromethylation) of arynes with [CuCF3] in the presence of an oxidant DDQ. The method allows the rapid construction of a new class of 1,2-bis(trifluoromethyl)arenes in one-step from aryne precursors under mild conditions. Its synthetic utility has been demonstrated in the preparation of bis(trifluoromethylated) molecules with potential pharmaceutical and materials science applications. Mechanistic studies indicated the presence of an o-trifluoromethyl aryl radical intermediate via CF3 group transfer from [CuCF3] to the aryne.
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Affiliation(s)
- Xinkan Yang
- Department of Chemistry , The Chinese University of Hong Kong , Shatin , New Territories , Hong Kong SAR .
| | - Gavin Chit Tsui
- Department of Chemistry , The Chinese University of Hong Kong , Shatin , New Territories , Hong Kong SAR .
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15
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Abstract
A closer look is given to the successful approaches to the C(sp3)–F activation of benzylic, allylic, propargylic and allenylic fluorides.
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16
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Xu L, Zhang Q, Xie Q, Huang B, Dai JJ, Xu J, Xu HJ. Pd-catalyzed defluorination/arylation of α-trifluoromethyl ketones via consecutive β-F elimination and C–F bond activation. Chem Commun (Camb) 2018; 54:4406-4409. [DOI: 10.1039/c8cc01568f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pd-catalyzed selective activation of a CF3 group by consecutive β-F elimination and C–F oxidative addition is reported herein.
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Affiliation(s)
- Lei Xu
- School of Biology and Medical Engineering
- Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei University of Technology Hefei
- P. R. China
| | - Qi Zhang
- Institute of Industry & Equipment Technology
- Hefei University of Technology Hefei
- P. R. China
| | - Qiang Xie
- PET-CT Center, The First Affiliated Hospital of USTC
- Hefei
- P. R. China
| | - Bei Huang
- School of Biology and Medical Engineering
- Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei University of Technology Hefei
- P. R. China
| | - Jian-Jun Dai
- School of Biology and Medical Engineering
- Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei University of Technology Hefei
- P. R. China
| | - Jun Xu
- School of Biology and Medical Engineering
- Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei University of Technology Hefei
- P. R. China
| | - Hua-Jian Xu
- School of Biology and Medical Engineering
- Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei University of Technology Hefei
- P. R. China
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17
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Mallov I, Ruddy AJ, Zhu H, Grimme S, Stephan DW. C−F Bond Activation by Silylium Cation/Phosphine Frustrated Lewis Pairs: Mono-Hydrodefluorination of PhCF3
, PhCF2
H and Ph2
CF2. Chemistry 2017; 23:17692-17696. [DOI: 10.1002/chem.201705276] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Ian Mallov
- Department of Chemistry; University of Toronto; 80 St. George St Toronto Ontario M5S 3H6 Canada
| | - Adam J. Ruddy
- Department of Chemistry; University of Toronto; 80 St. George St Toronto Ontario M5S 3H6 Canada
| | - Hui Zhu
- Mulliken Center for Theoretical Chemistry; Institut für Physikalische und Theoretische Chemie; Universität Bonn; Beringstr. 4 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry; Institut für Physikalische und Theoretische Chemie; Universität Bonn; Beringstr. 4 53115 Bonn Germany
| | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George St Toronto Ontario M5S 3H6 Canada
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18
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Wang L, Wei J, Wu R, Cheng G, Li X, Hu J, Hu Y, Sheng R. The stability and reactivity of tri-, di-, and monofluoromethyl/methoxy/methylthio groups on arenes under acidic and basic conditions. Org Chem Front 2017. [DOI: 10.1039/c6qo00674d] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The stability and reactivity of tri-, di- and monofluoromethyl groups under acidic and basic conditions are described.
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Affiliation(s)
- Lingfei Wang
- College of Pharmaceutical Sciences
- Zhejiang University
- Hangzhou 310058
- P. R. China
| | - Jun Wei
- College of Pharmaceutical Sciences
- Zhejiang University
- Hangzhou 310058
- P. R. China
| | - Ranran Wu
- College of Pharmaceutical Sciences
- Zhejiang University
- Hangzhou 310058
- P. R. China
| | - Gang Cheng
- College of Pharmaceutical Sciences
- Zhejiang University
- Hangzhou 310058
- P. R. China
| | - Xinjin Li
- Key Laboratory of Organofluorine Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- P. R. China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- P. R. China
| | - Yongzhou Hu
- College of Pharmaceutical Sciences
- Zhejiang University
- Hangzhou 310058
- P. R. China
| | - Rong Sheng
- College of Pharmaceutical Sciences
- Zhejiang University
- Hangzhou 310058
- P. R. China
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19
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Saito K, Umi T, Yamada T, Suga T, Akiyama T. Niobium(v)-catalyzed defluorinative triallylation of α,α,α-trifluorotoluene derivatives by triple C–F bond activation. Org Biomol Chem 2017; 15:1767-1770. [DOI: 10.1039/c6ob02825j] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The conjugation between the carbocation center and the adjacent fluorine atoms worked effectively in the cascade defluorinative triallylation of α,α,α-trifluorotoluene derivatives.
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Affiliation(s)
- Kodai Saito
- Department of Chemistry
- Gakushuin University
- Tokyo 171-8588
- Japan
| | - Taishi Umi
- Department of Chemistry
- Gakushuin University
- Tokyo 171-8588
- Japan
| | - Takayuki Yamada
- Department of Chemistry
- Gakushuin University
- Tokyo 171-8588
- Japan
| | - Takuya Suga
- Department of Chemistry
- Gakushuin University
- Tokyo 171-8588
- Japan
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20
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Sumita A, Otani Y, Ohwada T. Tandem buildup of complexity of aromatic molecules through multiple successive electrophile generation in one pot, controlled by varying the reaction temperature. Org Biomol Chem 2016; 14:1680-93. [PMID: 26699842 DOI: 10.1039/c5ob02240a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
While some sequential electrophilic aromatic substitution reactions, known as tandem/domino/cascade reactions, have been reported for the construction of aromatic single skeletons, one of the most interesting and challenging possibilities remains the one-pot build-up of a complex aromatic molecule from multiple starting components, i.e., ultimately multi-component electrophilic aromatic substitution reactions. In this work, we show how tuning of the leaving group ability of phenolate derivatives from carbamates and esters provides a way to successively generate multiple unmasked electrophiles in a controlled manner in one pot, simply by varying the temperature. Here, we demonstrate the autonomous formation of up to three bonds in one pot and formation of two bonds arising from a three-component electrophilic aromatic substitution reaction. This result provides a proof-of-concept of our strategy applicable for the self-directed construction of complex aromatic structures from multiple simple molecules, which can be a potential avenue to realize multi-component electrophilic aromatic substitution reactions.
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Affiliation(s)
- Akinari Sumita
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Yuko Otani
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Tomohiko Ohwada
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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Papaianina O, Amsharov KY. Aluminum oxide mediated C–F bond activation in trifluoromethylated arenes. Chem Commun (Camb) 2016; 52:1505-8. [DOI: 10.1039/c5cc08747c] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thermally activated γ-aluminium oxide was found to be very effective for C–F bond activation in trifluoromethylated arenes.
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Affiliation(s)
- O. Papaianina
- Institute of Organic Chemistry II
- University Erlangen-Nuernberg
- 91054 Erlangen
- Germany
| | - K. Yu. Amsharov
- Institute of Organic Chemistry II
- University Erlangen-Nuernberg
- 91054 Erlangen
- Germany
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Zhu J, Pérez M, Caputo CB, Stephan DW. Use of Trifluoromethyl Groups for Catalytic Benzylation and Alkylation with Subsequent Hydrodefluorination. Angew Chem Int Ed Engl 2015; 55:1417-21. [DOI: 10.1002/anie.201510494] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Indexed: 11/05/2022]
Affiliation(s)
- Jiangtao Zhu
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
| | - Manuel Pérez
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
| | - Christopher B. Caputo
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
| | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
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Zhu J, Pérez M, Caputo CB, Stephan DW. Use of Trifluoromethyl Groups for Catalytic Benzylation and Alkylation with Subsequent Hydrodefluorination. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201510494] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jiangtao Zhu
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
| | - Manuel Pérez
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
| | - Christopher B. Caputo
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
| | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George Street Toronto Ontario M5S 3H6 Canada
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Yamada T, Saito K, Akiyama T. Transformation of Trifluorotoluenes Triggered by Titanium(IV) Chloride-Catalyzed Hydrodefluorination using Hydrosilanes. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201500920] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Shen Q, Huang YG, Liu C, Xiao JC, Chen QY, Guo Y. Review of recent advances in CF bond activation of aliphatic fluorides. J Fluor Chem 2015. [DOI: 10.1016/j.jfluchem.2015.07.007] [Citation(s) in RCA: 173] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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26
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Champagne PA, Drouin M, Legault CY, Audubert C, Paquin JF. Revised mechanistic explanation for the alcohol-promoted amination of benzylic fluorides under highly concentrated conditions: Computational and experimental evidence on a model substrate. J Fluor Chem 2015. [DOI: 10.1016/j.jfluchem.2014.08.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kurouchi H, Sumita A, Otani Y, Ohwada T. Protonation switching to the least-basic heteroatom of carbamate through cationic hydrogen bonding promotes the formation of isocyanate cations. Chemistry 2014; 20:8682-90. [PMID: 24920101 DOI: 10.1002/chem.201402447] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Indexed: 11/07/2022]
Abstract
We found that phenethylcarbamates that bear ortho-salicylate as an ether group (carbamoyl salicylates) dramatically accelerate OC bond dissociation in strong acid to facilitate generation of isocyanate cation (N-protonated isocyanates), which undergo subsequent intramolecular aromatic electrophilic cyclization to give dihydroisoquinolones. To generate isocyanate cations from carbamates in acidic media as electrophiles for aromatic substitution, protonation at the ether oxygen, the least basic heteroatom, is essential to promote CO bond cleavage. However, the carbonyl oxygen of carbamates, the most basic site, is protonated exclusively in strong acids. We found that the protonation site can be shifted to an alternative basic atom by linking methyl salicylate to the ether oxygen of carbamate. The methyl ester oxygen ortho to the phenolic (ether) oxygen of salicylate is as basic as the carbamate carbonyl oxygen, and we found that monoprotonation at the methyl ester oxygen in strong acid resulted in the formation of an intramolecular cationic hydrogen bond (>CO(+) H⋅⋅⋅O<) with the phenolic ether oxygen. This facilitates OC bond dissociation of phenethylcarbamates, thereby promoting isocyanate cation formation. In contrast, superacid-mediated diprotonation at the methyl ester oxygen of the salicylate and the carbonyl oxygen of the carbamate afforded a rather stable dication, which did not readily undergo CO bond dissociation. This is an unprecedented and unknown case in which the monocation has greater reactivity than the dication.
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Affiliation(s)
- Hiroaki Kurouchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5841-4735
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Naredla RR, Klumpp DA. Contemporary Carbocation Chemistry: Applications in Organic Synthesis. Chem Rev 2013; 113:6905-48. [DOI: 10.1021/cr4001385] [Citation(s) in RCA: 263] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Rajasekhar Reddy Naredla
- Department of Chemistry
and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115,
United States
| | - Douglas A. Klumpp
- Department of Chemistry
and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115,
United States
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