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Lopez Lemus MS, Kavthe RD, Thomas RM, Baumann M, Iyer KS, Lipshutz BH. Nickel-Catalyzed Hydro- and Deutero-dehalogenations of (Hetero)Aryl Halides under Aqueous Micellar Catalysis Conditions. CHEMSUSCHEM 2025:e202500043. [PMID: 40273112 DOI: 10.1002/cssc.202500043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2025] [Revised: 02/28/2025] [Indexed: 04/26/2025]
Abstract
Efficient Ni-catalyzed hydrodehalogenations and deuterodehalogenations of aryl/heteroaryl halides are reported herein. This new technology can be used to incorporate not only hydrogen, but also deuterium into various aromatic/heteroaromatic compounds with high efficiency, using 2-6 mol % nickel in the presence of stoichiometric NaBH4. Over 40 examples have been successfully converted to the corresponding (hetero)arenes in excellent yields. The process is conducted under green chemistry conditions: in water enabled by designer surfactants, a medium which can be readily recycled. Minimal organic solvent, needed given the small (academic) scale of the reactions, is used for product isolation, resulting in low E-Factors. Additionally, sterically hindered substrates are amenable, as are selected APIs that feature carbon-fluorine bonds.
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Affiliation(s)
- Monica S Lopez Lemus
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Rahul D Kavthe
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Rohan M Thomas
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Max Baumann
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Karthik S Iyer
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Bruce H Lipshutz
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
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2
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Davis RL, Grotjahn S, Koenig B, Buck DJ, Weaver JD. Novel fluorinated cannabinoid analogs modulate cytokine expression in human C20 microglial cells. Pharmacol Rep 2025; 77:295-301. [PMID: 39612133 DOI: 10.1007/s43440-024-00680-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2024] [Revised: 10/28/2024] [Accepted: 11/18/2024] [Indexed: 11/30/2024]
Abstract
BACKGROUND Phytochemicals derived from the plant Cannabis sativa hold promise in terms of medicinal value. Cannabinoids such as Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN) are arguably the best characterized and known to possess wide-ranging therapeutic benefits. The mechanism of action for these therapeutic effects remains to be fully elucidated, however, the anti-inflammatory actions are of particular interest. Maximizing therapeutic effects while limiting adverse effects is crucial in pharmaceutical development. Fluorination of natural products often yields molecules with enhanced biological properties and provides opportunities for intellectual property protection not available to the natural product. METHODS Herein, we describe four novel cannabinoids (a deoxy trifluoroCBN analog (F3CBN), the racemic cis-deoxy-trifluoro-THC (F3THC), and truncated pyridine analogs of an intermediate in route to the THC and CBN, SG126 and SG154. Importantly, we provide the initial assessment of the biologic activity of these molecules, by investigating the in vitro effects on metabolic activity (via 3-[4,5-dimethylthiazol-2-yl]-2,5,-diphenyltetrazolium bromide, MTT assay) and cytokine expression (via enzyme linked immunosorbent assay, ELISA) in human C20 microglial cells. RESULTS The cannabinoids examined had minimal to no effect on metabolic activity up to 10 µM. Notably, F3CBN and F3THC potentiated interleukin-1 β (IL-1β)-induced expression of interferon-γ inducible protein 10 (CXCL10) and IL-6 expression whereas, SG126 and SG154 were inhibitory. CONCLUSIONS These findings are foundational for new lines of investigation into the therapeutic potential of four novel fluorinated cannabinoids.
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Affiliation(s)
- Randall L Davis
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, 1111 W. 17th Street, Tulsa, OK, 74107, USA.
| | - Sascha Grotjahn
- Institut für Organische Chemie, Universität Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Burkhard Koenig
- Institut für Organische Chemie, Universität Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Daniel J Buck
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, 1111 W. 17th Street, Tulsa, OK, 74107, USA
| | - Jimmie D Weaver
- Department of Chemistry, Oklahoma State University, 107 Physical Sciences, Stillwater, OK, 74078, USA
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3
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Liu DH, Ma J. Recent Advances in Dearomative Partial Reduction of Benzenoid Arenes. Angew Chem Int Ed Engl 2024; 63:e202402819. [PMID: 38480464 DOI: 10.1002/anie.202402819] [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: 02/07/2024] [Indexed: 04/11/2024]
Abstract
Dearomative partial reduction is an extraordinary approach for transforming benzenoid arenes and has been well-known for many decades, as exemplified by the dehydrogenation of Birch reduction and the hydroarylation of Crich addition. Despite its remarkable importance in synthesis, this field has experienced slow progress over the last half-century. However, a revival has been observed with the recent introduction of electrochemical and photochemical methods. In this Minireview, we summarize the recent advancements in dearomative partial reduction of benzenoid arenes, including dihydrogenation, hydroalkylation, arylation, alkenylation, amination, borylation and others. Further, the intriguing utilization of dearomative partial reduction in the synthesis of natural products is also emphasized. It is anticipated that this Minireview will stimulate further progress in arene dearomative transformations.
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Affiliation(s)
- De-Hai Liu
- Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering and Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Jiajia Ma
- Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering and Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
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4
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Zubkov MO, Dilman AD. Radical reactions enabled by polyfluoroaryl fragments: photocatalysis and beyond. Chem Soc Rev 2024; 53:4741-4785. [PMID: 38536104 DOI: 10.1039/d3cs00889d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Polyfluoroarenes have been known for a long time, but they are most often used as fluorinated building blocks for the synthesis of aromatic compounds. At the same time, due to peculiar fluorine effect, they have unique properties that provide applications in various fields ranging from synthesis to materials science. This review summarizes advances in the radical chemistry of polyfluoroarenes, which have become possible mainly with the advent of photocatalysis. Transformations of the fluorinated ring via the C-F bond activation, as well as use of fluoroaryl fragments as activating groups and hydrogen atom transfer agents are discussed. The ability of fluoroarenes to serve as catalysts is also considred.
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Affiliation(s)
- Mikhail O Zubkov
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky prosp. 47, 119991 Moscow, Russian Federation.
| | - Alexander D Dilman
- N. D. Zelinsky Institute of Organic Chemistry, Leninsky prosp. 47, 119991 Moscow, Russian Federation.
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5
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Grotjahn S, Graf C, Zelenka J, Pattanaik A, Müller L, Kutta RJ, Rehbein J, Roithová J, Gschwind RM, Nuernberger P, König B. Reactivity of Superbasic Carbanions Generated via Reductive Radical-Polar Crossover in the Context of Photoredox Catalysis. Angew Chem Int Ed Engl 2024; 63:e202400815. [PMID: 38408163 DOI: 10.1002/anie.202400815] [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: 01/12/2024] [Revised: 02/06/2024] [Accepted: 02/09/2024] [Indexed: 02/28/2024]
Abstract
Photocatalytic reactions involving a reductive radical-polar crossover (RRPCO) generate intermediates with carbanionic reactivity. Many of these proposed intermediates resemble highly reactive organometallic compounds. However, conditions of their formation are generally not tolerated by their isolated organometallic versions and often a different reactivity is observed. Our investigations on their nature and reactivity under commonly used photocatalytic conditions demonstrate that these intermediates are indeed best described as free, superbasic carbanions capable of deprotonating common polar solvents usually assumed to be inert such as acetonitrile, dimethylformamide, and dimethylsulfoxide. Their basicity not only towards solvents but also towards electrophiles, such as aldehydes, ketones, and esters, is comparable to the reactivity of isolated carbanions in the gas-phase. Previously unsuccessful transformations thought to result from a lack of reactivity are explained by their high reactivity towards the solvent and weakly acidic protons of reaction partners. An intuitive explanation for the mode of action of photocatalytically generated carbanions is provided, which enables methods to verify reaction mechanisms proposed to involve an RRPCO step and to identify the reasons for the limitations of current methods.
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Affiliation(s)
- Sascha Grotjahn
- Faculty of Chemistry and Pharmacy, Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Christina Graf
- Faculty of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Jan Zelenka
- Department of Spectroscopy and Catalysis, Radboud University Nijmegen, Heyendaalseweg 135, 6525AJ, Nijmegen, the Netherlands
| | - Aryaman Pattanaik
- Faculty of Chemistry and Pharmacy, Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Lea Müller
- Faculty of Chemistry and Pharmacy, Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Roger Jan Kutta
- Faculty of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Julia Rehbein
- Faculty of Chemistry and Pharmacy, Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Jana Roithová
- Department of Spectroscopy and Catalysis, Radboud University Nijmegen, Heyendaalseweg 135, 6525AJ, Nijmegen, the Netherlands
| | - Ruth M Gschwind
- Faculty of Chemistry and Pharmacy, Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Patrick Nuernberger
- Faculty of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Burkhard König
- Faculty of Chemistry and Pharmacy, Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
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6
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Moore JT, Dorantes MJ, Pengmei Z, Schwartz TM, Schaffner J, Apps SL, Gaggioli CA, Das U, Gagliardi L, Blank DA, Lu CC. Light-Driven Hydrodefluorination of Electron-Rich Aryl Fluorides by an Anionic Rhodium-Gallium Photoredox Catalyst. Angew Chem Int Ed Engl 2022; 61:e202205575. [PMID: 36017770 PMCID: PMC9826370 DOI: 10.1002/anie.202205575] [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: 04/15/2022] [Indexed: 01/11/2023]
Abstract
An anionic Rh-Ga complex catalyzed the hydrodefluorination of challenging C-F bonds in electron-rich aryl fluorides and trifluoromethylarenes when irradiated with violet light in the presence of H2 , a stoichiometric alkoxide base, and a crown-ether additive. Based on theoretical calculations, the lowest unoccupied molecular orbital (LUMO), which is delocalized across both the Rh and Ga atoms, becomes singly occupied upon excitation, thereby poising the Rh-Ga complex for photoinduced single-electron transfer (SET). Stoichiometric and control reactions support that the C-F activation is mediated by the excited anionic Rh-Ga complex. After SET, the proposed neutral Rh0 intermediate was detected by EPR spectroscopy, which matched the spectrum of an independently synthesized sample. Deuterium-labeling studies corroborate the generation of aryl radicals during catalysis and their subsequent hydrogen-atom abstraction from the THF solvent to generate the hydrodefluorinated arene products. Altogether, the combined experimental and theoretical data support an unconventional bimetallic excitation that achieves the activation of strong C-F bonds and uses H2 and base as the terminal reductant.
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Affiliation(s)
- James T. Moore
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Michael J. Dorantes
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Zihan Pengmei
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Timothy M. Schwartz
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA,Institut für Anorganische ChemieUniversität BonnGerhard-Domagk-Str. 1Bonn53121Deutschland
| | - Jacob Schaffner
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Samantha L. Apps
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Carlo A. Gaggioli
- Department of ChemistryUniversity of Chicago5735 S Ellis Ave.ChicagoIllinois60637USA
| | - Ujjal Das
- Institut für Anorganische ChemieUniversität BonnGerhard-Domagk-Str. 1Bonn53121Deutschland
| | - Laura Gagliardi
- Department of ChemistryUniversity of Chicago5735 S Ellis Ave.ChicagoIllinois60637USA
| | - David A. Blank
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Connie C. Lu
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA,Institut für Anorganische ChemieUniversität BonnGerhard-Domagk-Str. 1Bonn53121Deutschland
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7
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Chen YJ, Deng WH, Guo JD, Ci RN, Zhou C, Chen B, Li XB, Guo XN, Liao RZ, Tung CH, Wu LZ. Transition-Metal-Free, Site-Selective C-F Arylation of Polyfluoroarenes via Electrophotocatalysis. J Am Chem Soc 2022; 144:17261-17268. [PMID: 36070360 DOI: 10.1021/jacs.2c08068] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Direct CAr-F arylation is effective and sustainable for synthesis of polyfluorobiaryls with different degrees of fluorination, which are important motifs in medical and material chemistry. However, with no aid of transition metals, the engagement of CAr-F bond activation has proved difficult. Herein, an unprecedented transition-metal-free strategy is reported for site-selective CAr-F arylation of polyfluoroarenes with simple (het)arenes. By merging N,N-bis(2,6-diisopropylphenyl)perylene-3,4,9,10-bis(dicarboximide)-catalyzed electrophotocatalytic reduction and anodic nitroxyl radical oxidation in an electrophotocatalytic cell, various polyfluoroaromatics (2F-6F and 8F), especially inactive partially fluorinated aromatics, undergo sacrificial-reagents-free C-F bond arylation with high regioselectivity, and the yields are comparable to those for reported transition-metal catalysis. This atom- and step-economic protocol features a paired electrocatalysis with organic mediators in both cathodic and anodic processes. The broad substrate scope and good functional-group compatibility highlight the merits of this operationally simple strategy. Moreover, the easy gram-scale synthesis and late-stage functionalization collectively advocate for the practical value, which would promote the vigorous development of fluorine chemistry.
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Affiliation(s)
- Ya-Jing Chen
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Wen-Hao Deng
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China
| | - Jia-Dong Guo
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Rui-Nan Ci
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Chao Zhou
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Bin Chen
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xu-Bing Li
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xiao-Ning Guo
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Rong-Zhen Liao
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China
| | - Chen-Ho Tung
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Li-Zhu Wu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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8
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Bo ZY, Yan SS, Gao TY, Song L, Ran CK, He Y, Zhang W, Cao GM, Yu DG. Visible-light photoredox-catalyzed selective carboxylation of C(sp2)−F bonds in polyfluoroarenes with CO2. CHINESE JOURNAL OF CATALYSIS 2022. [DOI: 10.1016/s1872-2067(22)64140-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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9
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Moore JT, Dorantes MJ, Pengmei Z, Schwartz TM, Schaffner J, Apps SL, Gaggioli CA, Das U, Gagliardi L, Blank DA, Lu CC. Light‐Driven Hydrodefluorination of Electron‐Rich Aryl Fluorides by an Anionic Rhodium‐Gallium Photoredox Catalyst. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- James T. Moore
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Michael J. Dorantes
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Zihan Pengmei
- University of Chicago Department of Chemistry Chemistry UNITED STATES
| | - Timothy M. Schwartz
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Inorganic Chemistry GERMANY
| | - Jacob Schaffner
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Samantha L. Apps
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Carlo A. Gaggioli
- University of Chicago Department of Chemistry Chemistry UNITED STATES
| | - Ujjal Das
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Inorganic Chemistry GERMANY
| | - Laura Gagliardi
- University of Chicago Department of Chemistry Chemistry UNITED STATES
| | - David A. Blank
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Connie C. Lu
- University of Minnesota College of Science and Engineering Chemistry Gerhard-Domagk-Straße 1 53121 Bonn GERMANY
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10
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Zhou L. Recent Advances in C-F Bond Cleavage Enabled by Visible Light Photoredox Catalysis. Molecules 2021; 26:molecules26227051. [PMID: 34834143 PMCID: PMC8621615 DOI: 10.3390/molecules26227051] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/16/2021] [Accepted: 11/19/2021] [Indexed: 12/05/2022] Open
Abstract
The creation of new bonds via C-F bond cleavage of readily available per- or oligofluorinated compounds has received growing interest. Using such a strategy, a myriad of valuable partially fluorinated products can be prepared, which otherwise are difficult to make by the conventional C-F bond formation methods. Visible light photoredox catalysis has been proven as an important and powerful tool for defluorinative reactions due to its mild, easy to handle, and environmentally benign characteristics. Compared to the classical C-F activation that proceeds via two-electron processes, radicals are the key intermediates using visible light photoredox catalysis, providing new modes for the cleavage of C-F bonds. In this review, a summary of the visible light-promoted C-F bond cleavage since 2018 was presented. The contents were classified by the fluorosubstrates, including polyfluorinated arenes, gem-difluoroalkenes, trifluoromethyl arenes, and trifluoromethyl alkenes. An emphasis is placed on the discussion of the mechanisms and limitations of these reactions. Finally, my personal perspective on the future development of this rapidly emerging field was provided.
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Affiliation(s)
- Lei Zhou
- School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, China
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11
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Wang J, Gao H, Shi C, Chen G, Tan X, Chen X, Xu L, Cai X, Huang B, Li H. Recent advances in radical-based C-F bond activation of polyfluoroarenes and gem-difluoroalkenes. Chem Commun (Camb) 2021; 57:12203-12217. [PMID: 34714301 DOI: 10.1039/d1cc04189d] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The direct employment of polyfluoroarenes and gem-difluoroalkenes as building blocks is regarded as one of the most effective and straightforward strategies for the introduction of fluorine-containing moieties into organic skeletons. Accordingly, radical chemistry has gradually become a mild and powerful method for the activation of their C-F bonds. The radical-based transformations of polyfluoroarenes and gem-difluoroalkenes can be primarily categorized into three types based on the specific intermediates involved: (1) multifluoroaryl radical anions, (2) monofluoroalkenyl radicals and (3) other radicals. Compared with the more established multifluoroaryl radical anion pathway, the monofluoroalkenyl radical-involved cross-coupling reaction can proceed through C-radical cross-coupling, radical addition/elimination or the hydrogen atom transfer process. For the presented examples in this review, the typical reaction modes, substrate scope, radical-involved mechanisms, and late-stage applications in the modification of bioactive molecules are discussed, aiming to provide a comprehensive overview of the recent advances of the radical-based transformations of polyfluoroarenes and gem-difluoroalkenes.
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Affiliation(s)
- Junlei Wang
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
| | - Han Gao
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Chengcheng Shi
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Guiling Chen
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
| | - Xia Tan
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
| | - Xuemei Chen
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
| | - Lei Xu
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
| | - Xiaodong Cai
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
| | - Binbin Huang
- College of Education for the Future, Beijing Normal University at Zhuhai, Zhuhai 519087, China.
| | - Hongqing Li
- School of Chemical Engineering, Guizhou Minzu University, Guiyang 550000, China.
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