1
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Lisboa AVRD, Duran-Camacho G, Ehrlacher AK, Lasky MR, Sanford MS. Deoxyfluorination of Carboxylic Acids via an In Situ Generated Trifluoromethoxide Salt. Org Lett 2023; 25:9025-9029. [PMID: 38064366 PMCID: PMC10774922 DOI: 10.1021/acs.orglett.3c03706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
An in situ generated pyridinium trifluoromethoxide salt (PyOCF3) is a highly effective deoxyfluorination reagent for the synthesis of acid fluorides. PyOCF3 is formed at room temperature from the reaction of 2,4-dinitro(trifluoromethoxy)benzene with 4-dimethylaminopyridine. PyOCF3 undergoes slow release of fluorophosgene and fluoride, which serve as the electrophile and nucleophile, respectively, for deoxyfluorination. A wide substrate scope and high functional group tolerance are demonstrated. Furthermore, the acid fluorides can be purified by filtration and telescoped to various known reactions.
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Affiliation(s)
- Al Vicente Riano D Lisboa
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Geraldo Duran-Camacho
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Annika K Ehrlacher
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Matthew R Lasky
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Melanie S Sanford
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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2
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Hooker LV, Bandar JS. Synthetic Advantages of Defluorinative C-F Bond Functionalization. Angew Chem Int Ed Engl 2023; 62:e202308880. [PMID: 37607025 PMCID: PMC10843719 DOI: 10.1002/anie.202308880] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/20/2023] [Accepted: 08/21/2023] [Indexed: 08/24/2023]
Abstract
Much progress has been made in the development of methods to both create compounds that contain C-F bonds and to functionalize C-F bonds. As such, C-F bonds are becoming common and versatile synthetic functional handles. This review summarizes the advantages of defluorinative functionalization reactions for small molecule synthesis. The coverage is organized by the type of carbon framework the fluorine is attached to for mono- and polyfluorinated motifs. The main challenges, opportunities and advances of defluorinative functionalization are discussed for each class of organofluorine. Most of the text focuses on case studies that illustrate how defluorofunctionalization can improve routes to synthetic targets or how the properties of C-F bonds enable unique mechanisms and reactions. The broader goal is to showcase the opportunities for incorporating and exploiting C-F bonds in the design of synthetic routes, improvement of specific reactions and advent of new methods.
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Affiliation(s)
- Leidy V Hooker
- Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, USA
| | - Jeffrey S Bandar
- Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, USA
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3
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Herbstritt D, Tomar P, Müller R, Kaupp M, Braun T. A 2,2-Difluoroimidazolidine Derivative for Deoxyfluorination Reactions: Mechanistic Insights by Experimental and Computational Studies. Chemistry 2023; 29:e202301556. [PMID: 37341145 DOI: 10.1002/chem.202301556] [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: 05/17/2023] [Revised: 06/20/2023] [Accepted: 06/20/2023] [Indexed: 06/22/2023]
Abstract
A N-heterocyclic deoxyfluorinating agent SIMesF2 was synthesized by nucleophilic fluorination of N,N-1,3-dimesityl-2-chloroimidazolidinium chloride (3) at room temperature. SIMesF2 was applied to deoxyfluorinate carboxylic acids and alcohols and convert benzaldehyde into difluorotoluene. Mechanistic studies by NMR spectroscopy suggest reaction pathways of the carboxylic acid to acyl fluoride via outer-sphere fluorinations at an imidazolidinium ion by polyfluoride. DFT studies give further insight by exploring mechanistic details which distinguish the fluorination of aldehydes from that of carboxylic acids. Furthermore, a consecutive reaction sequence for the oxidation of an aldehyde followed by in situ fluorination of the generated carboxylic acid was developed.
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Affiliation(s)
- Domenique Herbstritt
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Pooja Tomar
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Robert Müller
- Institut für Chemie, Technische Universität Berlin, Theoretische Chemie/Quantenchemie, Sekr.C7, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Martin Kaupp
- Institut für Chemie, Technische Universität Berlin, Theoretische Chemie/Quantenchemie, Sekr.C7, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Thomas Braun
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
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4
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Zhang H, Wu J, Zhang X, Fan M. LiBF 4-Promoted Aromatic Fluorodetriazenation under Mild Conditions. J Org Chem 2023; 88:12826-12834. [PMID: 37594375 DOI: 10.1021/acs.joc.3c01239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
An efficient and mild fluorination method through LiBF4-promoted aromatic fluorodetriazenation of 3,3-dimethyl-1-aryltriazenes is developed. The reaction proceeds smoothly and tends to complete within 2 h in the absence of a protic acid or strong Lewis acid. This method tolerates a wide range of functional groups and affords the aryl fluoride products in moderate to excellent yields.
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Affiliation(s)
- Hongjin Zhang
- Academy of Medical Engineering and Translational Medicine (AMT), Tianjin University, Tianjin 300072, P.R. China
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310018, P.R. China
| | - Jianbo Wu
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, P.R. China
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310018, P.R. China
| | - Xingxian Zhang
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, P.R. China
| | - Mengyang Fan
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310018, P.R. China
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5
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Hattori H, Ogiwara Y, Sakai N. Formation, Characterization, and Reactivity of Acyl Palladium Complexes in Pd(OAc) 2/PCy 3-Catalyzed Transformation of Acyl Fluorides. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hiroyuki Hattori
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Yohei Ogiwara
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Norio Sakai
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
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6
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Morgan P, Saunders GC, Macgregor SA, Marr AC, Licence P. Nucleophilic Fluorination Catalyzed by a Cyclometallated Rhodium Complex. Organometallics 2022; 41:883-891. [PMID: 35571260 PMCID: PMC9098193 DOI: 10.1021/acs.organomet.2c00052] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Indexed: 11/30/2022]
Abstract
Quantitative catalytic nucleophilic fluorination of a range of acyl chlorides to acyl fluorides was promoted by a cyclometallated rhodium complex [(η5,κ2C-C5Me4CH2C6F5CH2NC3H2NMe)- RhCl] (1). 1 can be prepared in high yields from commercially available starting materials using a one-pot method. The catalyst could be separated, regenerated, and reused. Rapid quantitative fluorination generated the fluoride analogue of the active pharmaceutical ingredient probenecid. Infrared in situ monitoring verified the clean conversion of the substrates to products. VTNA graphical kinetic analysis and DFT calculations lead to a postulated reaction mechanism involving a nucleophilic Rh-F bond.
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Affiliation(s)
- Patrick
J. Morgan
- GSK
Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, U.K.
| | | | - Stuart A. Macgregor
- School
of Engineering and Physical Sciences, Heriot-Watt
University, William H. Perkin Building, Edinburgh EH14 4AS, U.K.
| | - Andrew C. Marr
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, David Keir Building, Belfast BT9 5AG, U.K.
| | - Peter Licence
- GSK
Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, U.K.
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7
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Visible-light induced transition-metal and photosensitizer-free conversion of aldehydes to acyl fluorides under mild conditions. GREEN SYNTHESIS AND CATALYSIS 2022. [DOI: 10.1016/j.gresc.2022.04.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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8
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Tetramethylammonium Fluoride: Fundamental Properties and Applications in C-F Bond-Forming Reactions and as a Base. Catalysts 2022. [DOI: 10.3390/catal12020233] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Nucleophilic ionic sources of fluoride are essential reagents in the synthetic toolbox to access high added-value fluorinated building blocks unattainable by other means. In this review, we provide a concise description and rationale of the outstanding features of one of these reagents, tetramethylammonium fluoride (TMAF), as well as disclosing the different methods for its preparation, and how its physicochemical properties and solvation effects in different solvents are intimately associated with its reactivity. Furthermore, herein we also comprehensively describe its historic and recent utilization, up to December 2021, in C-F bond-forming reactions with special emphasis on nucleophilic aromatic substitution fluorinations with a potential sustainable application in industrial settings, as well as its use as a base capable of rendering unprecedented transformations.
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9
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Convenient and efficient access to tri- and tetra-substituted 4-fluoropyridines via a [3 + 2]/[2 + 1] cyclization reaction. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.02.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Petitpoisson L, Pichette A, Alsarraf J. Towards better syntheses of partially methylated carbohydrates? Org Chem Front 2022. [DOI: 10.1039/d2qo00893a] [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
We give an overview of the reported synthetic strategies towards partially methylated glycosides and discuss how better protocols could stem from catalytic site-selective transformations of carbohydrates and cleaner methylation reagents.
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Affiliation(s)
- Lucas Petitpoisson
- Centre de recherche sur la boréalie (CREB), Laboratoire d'analyse et de séparation des essences végétales (LASEVE), Université du Québec à Chicoutimi, 555 boulevard de l'Université, Chicoutimi G7H 2B1, Québec, Canada
| | - André Pichette
- Centre de recherche sur la boréalie (CREB), Laboratoire d'analyse et de séparation des essences végétales (LASEVE), Université du Québec à Chicoutimi, 555 boulevard de l'Université, Chicoutimi G7H 2B1, Québec, Canada
| | - Jérôme Alsarraf
- Centre de recherche sur la boréalie (CREB), Laboratoire d'analyse et de séparation des essences végétales (LASEVE), Université du Québec à Chicoutimi, 555 boulevard de l'Université, Chicoutimi G7H 2B1, Québec, Canada
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11
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12
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Brittain WDG, Cobb SL. Carboxylic Acid Deoxyfluorination and One-Pot Amide Bond Formation Using Pentafluoropyridine (PFP). Org Lett 2021; 23:5793-5798. [PMID: 34251217 PMCID: PMC8397423 DOI: 10.1021/acs.orglett.1c01953] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This work describes the application of pentafluoropyridine (PFP), a cheap commercially available reagent, in the deoxyfluorination of carboxylic acids to acyl fluorides. The acyl fluorides can be formed from a range of acids under mild conditions. We also demonstrate that PFP can be utilized in a one-pot amide bond formation via in situ generation of acyl fluorides. This one-pot deoxyfluorination amide bond-forming reaction gives ready access to amides in yields of ≤94%.
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Affiliation(s)
- William D G Brittain
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom
| | - Steven L Cobb
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom
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13
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Morales-Colón MT, See YY, Lee SJ, Scott PJH, Bland DC, Sanford MS. Tetramethylammonium Fluoride Alcohol Adducts for S NAr Fluorination. Org Lett 2021; 23:4493-4498. [PMID: 34029110 DOI: 10.1021/acs.orglett.1c01490] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Nucleophilic aromatic fluorination (SNAr) is among the most common methods for the formation of C(sp2)-F bonds. Despite many recent advances, a long-standing limitation of these transformations is the requirement for rigorously dry, aprotic conditions to maintain the nucleophilicity of fluoride and suppress the generation of side products. This report addresses this challenge by leveraging tetramethylammonium fluoride alcohol adducts (Me4NF·ROH) as fluoride sources for SNAr fluorination. Through systematic tuning of the alcohol substituent (R), tetramethylammonium fluoride tert-amyl alcohol (Me4NF·t-AmylOH) was identified as an inexpensive, practical, and bench-stable reagent for SNAr fluorination under mild and convenient conditions (80 °C in DMSO, without the requirement for drying of reagents or solvent). A substrate scope of more than 50 (hetero) aryl halides and nitroarene electrophiles is demonstrated.
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Affiliation(s)
- María T Morales-Colón
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Yi Yang See
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - So Jeong Lee
- Department of Radiology, University of Michigan, 1301 Catherine, Ann Arbor, Michigan 48109, United States
| | - Peter J H Scott
- Department of Radiology, University of Michigan, 1301 Catherine, Ann Arbor, Michigan 48109, United States
| | - Douglas C Bland
- Process Sciences & Technology, Corteva Agriscience, 9330 Zionsville Road, Indianapolis, Indiana 46268, United States
| | - Melanie S Sanford
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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14
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Mao S, Kramer JH, Sun H. Deoxyfluorination of Carboxylic Acids with KF and Highly Electron-Deficient Fluoroarenes. J Org Chem 2021; 86:6066-6074. [PMID: 33876634 DOI: 10.1021/acs.joc.0c02491] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A deoxyfluorination reaction of carboxylic acids using potassium fluoride (KF) and highly electron-deficient fluoroarenes is reported here, giving acyl fluorides in moderate to excellent yield (57-92% based on NMR integration and 34-95% for isolated examples).
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Affiliation(s)
- Siyu Mao
- Department of Chemistry & Center for Fluorinated Functional Materials, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Jordan H Kramer
- Department of Chemistry & Center for Fluorinated Functional Materials, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Haoran Sun
- Department of Chemistry & Center for Fluorinated Functional Materials, University of South Dakota, Vermillion, South Dakota 57069, United States
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15
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Hawk MK, Ryan SJ, Zhang X, Huang P, Chen J, Liu C, Chen J, Lindsay-Scott PJ, Burnett J, White C, Lu Y, Rizzo JR. Tetramethylammonium Fluoride Tetrahydrate for SNAr Fluorination of 4-Chlorothiazoles at a Production Scale. Org Process Res Dev 2021. [DOI: 10.1021/acs.oprd.1c00042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mai Khanh Hawk
- Small Molecule Design and Development (SMDD), Lilly Technology Center North, Eli Lilly and Company, 1400 W Raymond Street, Indianapolis, Indiana 46221, United States
| | - Sarah J. Ryan
- Small Molecule Design and Development (SMDD), Lilly Technology Center North, Eli Lilly and Company, 1400 W Raymond Street, Indianapolis, Indiana 46221, United States
| | - Xin Zhang
- STA Pharmaceutical (WuXi STA), A Subsidiary of WuXi AppTec., No. 7 Building, #90 Delin Rd, WaiGaoQiao Free Trade
Zone, Shanghai 200131, People’s Republic of China
| | - Ping Huang
- STA Pharmaceutical (WuXi STA), A Subsidiary of WuXi AppTec., No. 7 Building, #90 Delin Rd, WaiGaoQiao Free Trade
Zone, Shanghai 200131, People’s Republic of China
| | - Jing Chen
- STA Pharmaceutical (WuXi STA), A Subsidiary of WuXi AppTec., No. 7 Building, #90 Delin Rd, WaiGaoQiao Free Trade
Zone, Shanghai 200131, People’s Republic of China
| | - Chuanren Liu
- STA Pharmaceutical (WuXi STA), A Subsidiary of WuXi AppTec., No. 7 Building, #90 Delin Rd, WaiGaoQiao Free Trade
Zone, Shanghai 200131, People’s Republic of China
| | - Jianping Chen
- STA Pharmaceutical (WuXi STA), A Subsidiary of WuXi AppTec., No. 7 Building, #90 Delin Rd, WaiGaoQiao Free Trade
Zone, Shanghai 200131, People’s Republic of China
| | | | - John Burnett
- Eli Lilly and Company Limited, Erl Wood Manor, Windlesham, Surrey GU20 6PH, U.K
| | - Craig White
- Eli Lilly and Company Limited, Erl Wood Manor, Windlesham, Surrey GU20 6PH, U.K
| | - Yu Lu
- Small Molecule Design and Development (SMDD), Lilly Technology Center North, Eli Lilly and Company, 1400 W Raymond Street, Indianapolis, Indiana 46221, United States
| | - John R. Rizzo
- Small Molecule Design and Development (SMDD), Lilly Technology Center North, Eli Lilly and Company, 1400 W Raymond Street, Indianapolis, Indiana 46221, United States
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16
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Hong CM, Whittaker AM, Schultz DM. Nucleophilic Fluorination of Heteroaryl Chlorides and Aryl Triflates Enabled by Cooperative Catalysis. J Org Chem 2021; 86:3999-4006. [DOI: 10.1021/acs.joc.0c02845] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Cynthia M. Hong
- Department of Process Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065 United States
| | - Aaron M. Whittaker
- Department of Process Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065 United States
| | - Danielle M. Schultz
- Department of Process Research and Development, MRL, Merck & Co., Inc., Rahway, New Jersey 07065 United States
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17
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Le B, Wu H, Hu X, Zhou X, Guo Y, Chen QY, Liu C. Rapid synthesis of acyl fluorides from carboxylic acids with Cu(O2CCF2SO2F)2. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Abstract
A new organocatalyzed fluoride metathesis reaction between fluoroarenes and carbonyl derivatives is reported. The reaction exchanges fluoride (F-) and alternate nucleophiles (OAc-, OCO2R-, SR-, Cl-, CN-, NCS-). The approach provides a conceptually novel route to manipulate the fluorine content of organic molecules. When the fluorination and defluorination steps are combined into a single catalytic cycle, a byproduct free and 100% atom-efficient reaction can be achieved.
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Affiliation(s)
- Daniel Mulryan
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City, Shepherds Bush, London W12 0BZ, United Kingdom
| | - Andrew J P White
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City, Shepherds Bush, London W12 0BZ, United Kingdom
| | - Mark R Crimmin
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City, Shepherds Bush, London W12 0BZ, United Kingdom
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19
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See YY, Morales-Colón MT, Bland DC, Sanford MS. Development of S NAr Nucleophilic Fluorination: A Fruitful Academia-Industry Collaboration. Acc Chem Res 2020; 53:2372-2383. [PMID: 32969213 DOI: 10.1021/acs.accounts.0c00471] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The identification of reliable, general, and high yielding methods for the formation of C(sp2)-fluorine bonds remains a major challenge for synthetic organic chemists. A very common approach involves nucleophilic aromatic fluorination (SNAr fluorination) reactions of aryl chlorides or nitroarenes. Despite being known for more than a century, traditional SNAr fluorination reactions suffer from significant limitations, particularly on a process scale. These include the high cost of common reagents [e.g., cesium fluoride (CsF)], a requirement for elevated temperatures and long reaction times, poor functional group tolerance, and the need for rigorous exclusion of water. This Account summarizes our collaboration with Corteva Agriscience (previously Dow Agrosciences) to address many of these challenges. This collaboration has provided a platform for fundamental scientific advances involving the development of new methods, reagents, and substrates for mild and high yielding nucleophilic fluorination reactions.Our early studies established that the combination of potassium fluoride (KF) and superstoichiometric tetrabutylammonium chloride (Bu4NCl) serves as a cost-effective alternative to CsF for the SNAr fluorination of chloropicolinate substrates. However, these reactions still require elevated temperatures (>130 °C) and afford moderate yields due to competing decomposition of the substrate and product. The need for high temperature is largely due to slow reaction rates resulting from the low concentration of the active fluorinating reagent [anhydrous tetrabutylammonium fluoride (Bu4NF)] under these conditions. To address this issue, we developed several strategies for generating high concentration solutions of anhydrous tetraalkylammonium fluoride in situ by combining fluorine-containing electrophiles (e.g., hexafluorobenzene, acyl fluorides, sulfonyl fluorides) with tetraalkylammonium nucleophiles (R4NCN or R4NOR). These systems enable SNAr fluorination under unusually mild conditions, affording nearly quantitative yield with chloropicolinate substrates at room temperature. However, the high cost of the electrophiles and the generation of large quantities of byproducts in the R4NF-forming step render this approach unsuitable for process scale applications. As an alternative, we next explored anhydrous tetramethylammonium fluoride (Me4NF) for these transformations. This highly reactive fluoride source can be synthesized directly from inexpensive KF and Me4NCl and then dried by heating under vacuum. Unlike Bu4NF, it is not susceptible to Hofmann elimination. As such, anhydrous Me4NF is stable and isolable, as well as highly effective for the room temperature SNAr fluorination of chloropicolinates and other electron deficient substrates.The studies with anhydrous R4NF drew our attention to another challenge associated with traditional SNAr fluorination reactions: their limitation to substrates bearing resonance electron-withdrawing groups. We hypothesized that this challenge could be addressed by circumventing the Meisenheimer intermediate, a canonical mechanistic feature of SNAr fluorination. By designing reactions that involve an alternative concerted delivery of the fluoride to the ipso C(sp2) center, we developed a deoxyfluorination of arylfluorosulfonates using anhydrous Me4NF. This reaction exhibits a broad scope with respect to the aryl electrophile, with substrates bearing both electron-withdrawing (CN, ester, CF3, Cl) and moderately electron donating (phenyl, alkyl) substituents participating in deoxyfluorination. These deoxyfluorination conditions were also expanded to nonaromatic substrates, including aldehydes and benzylic/aliphatic alcohols.This Account concludes by delineating several ongoing challenges and opportunities in this fast-moving field. For instance, one important future direction will be to address the high moisture sensitivity of these transformations. In addition, the application of these new reagents and methods in the synthesis of pharmaceuticals, agrochemicals, and PET imaging agents will continue to test the versatility and functional group compatibility of these methods.
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Affiliation(s)
- Yi Yang See
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - María T. Morales-Colón
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Douglas C. Bland
- Product and Process Technology R&D, Corteva Agriscience, 9330 Zionsville Road, Indianapolis, Indiana 46268, United States
| | - Melanie S. Sanford
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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20
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Hong CM, Xu Y, Chung JYL, Schultz DM, Weisel M, Varsolona RJ, Zhong YL, Purohit AK, He CQ, Gauthier DR, Humphrey GR, Maloney KM, Lévesque F, Wang Z, Whittaker AM, Sirota E, McMullen JP. Development of a Commercial Manufacturing Route to 2-Fluoroadenine, The Key Unnatural Nucleobase of Islatravir. Org Process Res Dev 2020. [DOI: 10.1021/acs.oprd.0c00304] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Cynthia M. Hong
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Yingju Xu
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - John Y. L. Chung
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Danielle M. Schultz
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Mark Weisel
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Richard J. Varsolona
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Yong-Li Zhong
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Akasha K. Purohit
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Cyndi Q. He
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Donald R. Gauthier
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Guy R. Humphrey
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Kevin M. Maloney
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - François Lévesque
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Zhixun Wang
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Aaron M. Whittaker
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Eric Sirota
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Jonathan P. McMullen
- Process Research & Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
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21
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Affiliation(s)
| | - Yohei Ogiwara
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science
| | - Norio Sakai
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science
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22
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Morgan PJ, Hanson-Heine MWD, Thomas HP, Saunders GC, Marr AC, Licence P. C–F Bond Activation of a Perfluorinated Ligand Leading to Nucleophilic Fluorination of an Organic Electrophile. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00176] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Patrick J. Morgan
- GSK Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, United Kingdom
| | - Magnus W. D. Hanson-Heine
- GSK Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, United Kingdom
| | - Hayden P. Thomas
- School of Science, University of Waikato, Hamilton 3240, New Zealand
| | | | - Andrew C. Marr
- School of Chemistry and Chemical Engineering, Queen’s University Belfast, David Keir Building, Belfast BT9 5AG, United Kingdom
| | - Peter Licence
- GSK Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, United Kingdom
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23
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Ogiwara Y, Hosaka S, Sakai N. Benzoyl Fluorides as Fluorination Reagents: Reconstruction of Acyl Fluorides via Reversible Acyl C–F Bond Cleavage/Formation in Palladium Catalysis. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00028] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yohei Ogiwara
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Shintaro Hosaka
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Norio Sakai
- Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
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24
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Ogiwara Y, Sakai N. Acyl Fluorides in Late‐Transition‐Metal Catalysis. Angew Chem Int Ed Engl 2020; 59:574-594. [DOI: 10.1002/anie.201902805] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/01/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Yohei Ogiwara
- Department of Pure and Applied ChemistryFaculty of Science and TechnologyTokyo University of Science Noda Chiba 278-8510 Japan
| | - Norio Sakai
- Department of Pure and Applied ChemistryFaculty of Science and TechnologyTokyo University of Science Noda Chiba 278-8510 Japan
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25
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Cheng HG, Pu M, Kundu G, Schoenebeck F. Selective Methylation of Amides, N-Heterocycles, Thiols, and Alcohols with Tetramethylammonium Fluoride. Org Lett 2020; 22:331-334. [PMID: 31834810 DOI: 10.1021/acs.orglett.9b04400] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We herein disclose the use of tetramethylammonium fluoride (TMAF) as a direct and selective methylating agent of a variety of amides, indoles, pyrroles, imidazoles, alcohols, and thiols. The method is characterized by operational simplicity, wide scope, and ease of purification. Our computational studies suggest a concerted methylation-deprotonation as the preferred reaction pathway.
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Affiliation(s)
- Hong-Gang Cheng
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
| | - Maoping Pu
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
| | - Gourab Kundu
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
| | - Franziska Schoenebeck
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
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26
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Ogiwara Y, Sakai N. Carbonsäurefluoride in der Katalyse durch späte Übergangsmetalle. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902805] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yohei Ogiwara
- Department of Pure and Applied ChemistryFaculty of Science and TechnologyTokyo University of Science Noda Chiba 278-8510 Japan
| | - Norio Sakai
- Department of Pure and Applied ChemistryFaculty of Science and TechnologyTokyo University of Science Noda Chiba 278-8510 Japan
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27
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Munoz SB, Dang H, Ispizua-Rodriguez X, Mathew T, Prakash GKS. Direct Access to Acyl Fluorides from Carboxylic Acids Using a Phosphine/Fluoride Deoxyfluorination Reagent System. Org Lett 2019; 21:1659-1663. [PMID: 30840474 DOI: 10.1021/acs.orglett.9b00197] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A fast and simple method for deoxyfluorination of carboxylic acids is presented. The protocol employs commodity chemicals (PPh3, NBS, fluoride), affording products in excellent yields under mild conditions. Acyloxyphosphonium ion, the key reaction intermediate, was identified by NMR spectroscopic methods. Brønsted acidic conditions are essential for efficient C-F bond formation. The protocol displays scalability, high functional group tolerance, chemoselectivity, and easy purification of products. Deoxyfluorination of active pharmaceutical ingredients was established.
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Affiliation(s)
- Socrates B Munoz
- Loker Hydrocarbon Research Institute and Department of Chemistry , University of Southern California , Los Angeles , California 90089-1661 , United States
| | - Huong Dang
- Loker Hydrocarbon Research Institute and Department of Chemistry , University of Southern California , Los Angeles , California 90089-1661 , United States
| | - Xanath Ispizua-Rodriguez
- Loker Hydrocarbon Research Institute and Department of Chemistry , University of Southern California , Los Angeles , California 90089-1661 , United States
| | - Thomas Mathew
- Loker Hydrocarbon Research Institute and Department of Chemistry , University of Southern California , Los Angeles , California 90089-1661 , United States
| | - G K Surya Prakash
- Loker Hydrocarbon Research Institute and Department of Chemistry , University of Southern California , Los Angeles , California 90089-1661 , United States
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28
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Lim S, Song D, Jeon S, Kim Y, Kim H, Lee S, Cho H, Lee BC, Kim SE, Kim K, Lee E. Cobalt-Catalyzed C-F Bond Borylation of Aryl Fluorides. Org Lett 2018; 20:7249-7252. [PMID: 30388011 DOI: 10.1021/acs.orglett.8b03167] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A mild and practical cobalt-catalyzed defluoroborylation of fluoroarenes is presented for the first time. The method permits straightforward functionalization of fluoroarenes, with high selectivity for borylation of C-F over C-H bonds, and a tolerance for aerobic conditions. Furthermore, two-step 18F-fluorination was achieved for expanding the scope of 18F-positron emission tomography probes.
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Affiliation(s)
- Soobin Lim
- Center for Self-assembly and Complexity , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
| | - Dalnim Song
- Center for Self-assembly and Complexity , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
| | - Seungwon Jeon
- Center for Self-assembly and Complexity , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
| | - Youngsuk Kim
- Center for Self-assembly and Complexity , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
| | | | - Sanghee Lee
- Department of Nuclear Medicine , Seoul National University Bundang Hospital, Seoul National University College of Medicine , Seongnam 13620 , Republic of Korea.,Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology , Seoul National University , Suwon 16229 , Republic of Korea
| | | | - Byung Chul Lee
- Department of Nuclear Medicine , Seoul National University Bundang Hospital, Seoul National University College of Medicine , Seongnam 13620 , Republic of Korea.,Center for Nanomolecular Imaging and Innovative Drug Development , Advanced Institutes of Convergence Technology , Suwon 16229 , Republic of Korea
| | - Sang Eun Kim
- Department of Nuclear Medicine , Seoul National University Bundang Hospital, Seoul National University College of Medicine , Seongnam 13620 , Republic of Korea.,Center for Nanomolecular Imaging and Innovative Drug Development , Advanced Institutes of Convergence Technology , Suwon 16229 , Republic of Korea.,Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology , Seoul National University , Suwon 16229 , Republic of Korea
| | - Kimoon Kim
- Center for Self-assembly and Complexity , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
| | - Eunsung Lee
- Center for Self-assembly and Complexity , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
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29
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Schimler SD, Froese RDJ, Bland DC, Sanford MS. Reactions of Arylsulfonate Electrophiles with NMe4F: Mechanistic Insight, Reactivity, and Scope. J Org Chem 2018; 83:11178-11190. [DOI: 10.1021/acs.joc.8b01762] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Sydonie D. Schimler
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Robert D. J. Froese
- Core Research and Development, The Dow Chemical Company, 1710 Building, Midland, Michigan 48674, United States
| | - Douglas C. Bland
- Core Research and Development, The Dow Chemical Company, 1710 Building, Midland, Michigan 48674, United States
| | - Melanie S. Sanford
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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30
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Marzo L, Pagire SK, Reiser O, König B. Photokatalyse mit sichtbarem Licht: Welche Bedeutung hat sie für die organische Synthese? Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201709766] [Citation(s) in RCA: 306] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Leyre Marzo
- Institut für Organische Chemie; Universität Regensburg; Universitätsstraße 31 93053 Regensburg Deutschland
| | - Santosh K. Pagire
- Institut für Organische Chemie; Universität Regensburg; Universitätsstraße 31 93053 Regensburg Deutschland
| | - Oliver Reiser
- Institut für Organische Chemie; Universität Regensburg; Universitätsstraße 31 93053 Regensburg Deutschland
| | - Burkhard König
- Institut für Organische Chemie; Universität Regensburg; Universitätsstraße 31 93053 Regensburg Deutschland
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31
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Marzo L, Pagire SK, Reiser O, König B. Visible-Light Photocatalysis: Does It Make a Difference in Organic Synthesis? Angew Chem Int Ed Engl 2018; 57:10034-10072. [PMID: 29457971 DOI: 10.1002/anie.201709766] [Citation(s) in RCA: 1143] [Impact Index Per Article: 190.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 01/12/2018] [Indexed: 12/12/2022]
Abstract
Visible-light photocatalysis has evolved over the last decade into a widely used method in organic synthesis. Photocatalytic variants have been reported for many important transformations, such as cross-coupling reactions, α-amino functionalizations, cycloadditions, ATRA reactions, or fluorinations. To help chemists select photocatalytic methods for their synthesis, we compare in this Review classical and photocatalytic procedures for selected classes of reactions and highlight their advantages and limitations. In many cases, the photocatalytic reactions proceed under milder reaction conditions, typically at room temperature, and stoichiometric reagents are replaced by simple oxidants or reductants, such as air, oxygen, or amines. Does visible-light photocatalysis make a difference in organic synthesis? The prospect of shuttling electrons back and forth to substrates and intermediates or to selectively transfer energy through a visible-light-absorbing photocatalyst holds the promise to improve current procedures in radical chemistry and to open up new avenues by accessing reactive species hitherto unknown, especially by merging photocatalysis with organo- or metal catalysis.
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Affiliation(s)
- Leyre Marzo
- Institut für Organische Chemie, Universität Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Santosh K Pagire
- Institut für Organische Chemie, Universität Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Oliver Reiser
- Institut für Organische Chemie, Universität Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Burkhard König
- Institut für Organische Chemie, Universität Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
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32
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Revathi L, Ravindar L, Leng J, Rakesh KP, Qin HL. Synthesis and Chemical Transformations of Fluorosulfates. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201700591] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Lekkala Revathi
- School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan Hubei Province 430070 P. R. China
| | - Lekkala Ravindar
- School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan Hubei Province 430070 P. R. China
| | - Jing Leng
- School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan Hubei Province 430070 P. R. China
| | - Kadalipura Puttaswamy Rakesh
- School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan Hubei Province 430070 P. R. China
| | - Hua-Li Qin
- School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan Hubei Province 430070 P. R. China
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33
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Johansen MB, Lindhardt AT. Nucleophilic fluorination facilitated by a CsF–CaF2 packed bed reactor in continuous flow. Chem Commun (Camb) 2018; 54:825-828. [DOI: 10.1039/c7cc09035h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A simple to prepare, dry and handle packed bed reactor carrying CsF on CaF2, towards nucleophilic fluorinations in continuous flow, is reported.
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Affiliation(s)
- M. B. Johansen
- Department of Engineering
- Center for Carbon Dioxide Activation (CADIAC)
- Interdisciplinary Nanoscience Centre (iNANO)
- Aarhus University
- DK-8200 Aarhus N
| | - A. T. Lindhardt
- Department of Engineering
- Center for Carbon Dioxide Activation (CADIAC)
- Interdisciplinary Nanoscience Centre (iNANO)
- Aarhus University
- DK-8200 Aarhus N
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34
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Pliego JR. Potassium fluoride activation for the nucleophilic fluorination reaction using 18-crown-6, [2.2.2]-cryptand, pentaethylene glycol and comparison with the new hydro-crown scaffold: a theoretical analysis. Org Biomol Chem 2018; 16:3127-3137. [DOI: 10.1039/c8ob00418h] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ion-pair binding in the hydro-crown ether leads to more effective catalytic cycle for nucleophilic fluorination.
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Affiliation(s)
- Josefredo R. Pliego
- Departamento de Ciências Naturais
- Universidade Federal de São João del-Rei
- São João del-Rei
- Brazil
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35
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Veryser C, Demaerel J, Bieliu Nas V, Gilles P, De Borggraeve WM. Ex Situ Generation of Sulfuryl Fluoride for the Synthesis of Aryl Fluorosulfates. Org Lett 2017; 19:5244-5247. [PMID: 28901771 DOI: 10.1021/acs.orglett.7b02522] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A convenient transformation of phenols into the corresponding aryl fluorosulfates is presented: the first protocol to completely circumvent direct handling of gaseous sulfuryl fluoride (SO2F2). The proposed method employs 1,1'-sulfonyldiimidazole as a precursor to generate near-stoichiometric amounts of SO2F2 gas using a two-chamber reactor. With NMR studies, it was shown that this ex situ gas evolution is extremely rapid, and a variety of phenols and hydroxylated heteroarenes were fluorosulfated in good to excellent yields.
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Affiliation(s)
- Cedrick Veryser
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven , Celestijnenlaan 200F, Box 2404, 3001 Leuven, Belgium
| | - Joachim Demaerel
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven , Celestijnenlaan 200F, Box 2404, 3001 Leuven, Belgium
| | - Vidmantas Bieliu Nas
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven , Celestijnenlaan 200F, Box 2404, 3001 Leuven, Belgium
| | - Philippe Gilles
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven , Celestijnenlaan 200F, Box 2404, 3001 Leuven, Belgium
| | - Wim M De Borggraeve
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven , Celestijnenlaan 200F, Box 2404, 3001 Leuven, Belgium
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