1
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Sumii Y, Shibata N. Current State of Microflow Trifluoromethylation Reactions. CHEM REC 2023; 23:e202300117. [PMID: 37309300 DOI: 10.1002/tcr.202300117] [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: 04/03/2023] [Revised: 05/25/2023] [Indexed: 06/14/2023]
Abstract
The trifluoromethyl group is a powerful structural motif in drugs and polymers; thus, developing trifluoromethylation reactions is an important area of research in organic chemistry. Over the past few decades, significant progress has been made in developing new methods for the trifluoromethylation of organic molecules, ranging from nucleophilic and electrophilic approaches to transition-metal catalysis, photocatalysis, and electrolytic reactions. While these reactions were initially developed in batch systems, more recent microflow versions are highly attractive for industrial applications owing to their scalability, safety, and time efficiency. In this review, we discuss the current state of microflow trifluoromethylation. Approaches for microflow trifluoromethylation based on different trifluoromethylation reagents are described, including continuous flow, flow photochemical, microfluidic electrochemical reactions, and large-scale microflow reactions.
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Affiliation(s)
- Yuji Sumii
- Department of Engineering, Nagoya Institute of Technology, Gokiso, Showa-Ku, Nagoya, 466-8555, Japan
| | - Norio Shibata
- Department of Engineering, Nagoya Institute of Technology, Gokiso, Showa-Ku, Nagoya, 466-8555, Japan
- Department of Nanopharmaceutical Sciences, Department of Engineering, Nagoya Institute of Technology, Gokiso, Showa-Ku, Nagoya, 466-8555, Japan
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2
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Yang Y, Hammond GB, Umemoto T. Self-Sustaining Fluorination of Active Methylene Compounds and High-Yielding Fluorination of Highly Basic Aryl and Alkenyl Lithium Species with a Sterically Hindered N-Fluorosulfonamide Reagent. Angew Chem Int Ed Engl 2022; 61:e202211688. [PMID: 36066942 PMCID: PMC9588725 DOI: 10.1002/anie.202211688] [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: 08/09/2022] [Indexed: 11/11/2022]
Abstract
Fluorination of carbanions is pivotal for the synthesis of fluorinated compounds, but the current N-F fluorinating agents have significant drawbacks due to many reactive locations that surround the reactive N-F site. By developing a sterically hindered N-fluorosulfonamide reagent, namely N-fluoro-N-(tert-butyl)-tert-butanesulfonamide (NFBB), we discovered a conceptually novel base-catalyzed, self-sustaining fluorination of active methylene compounds and achieved the high-yielding fluorination of the hitherto difficult highly basic (hetero)aryl and alkenyl lithium species. In the former, the mild and high yield fluorination of active methylene compounds exhibited wide functional group tolerance and its novel catalytic fluorination-deprotonation cycle mechanism was demonstrated by deuterium-tracing experiments. In the latter, NFBB reacted with a variety of highly basic (hetero)aryl and alkenyl lithium species to provide the desired fluoro (hetero)arenes and alkenes in unprecedented high or quantitative yields.
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Affiliation(s)
- Yuhao Yang
- Department of Chemistry, University of Louisville, Louisville, KY 40292, USA
| | - Gerald B Hammond
- Department of Chemistry, University of Louisville, Louisville, KY 40292, USA
| | - Teruo Umemoto
- Department of Chemistry, University of Louisville, Louisville, KY 40292, USA
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3
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Yang Y, Hammond G, Umemoto T. Self‐Sustaining Fluorination of Active Methylene Compounds andFluorination of Aryl and Alkenyl Lithium Species with a StericallyHindered N‐Fluorosulfonamide Reagent. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202211688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yuhao Yang
- University of Louisville College of Arts and Sciences Chemistry UNITED STATES
| | - Gerald Hammond
- University of Louisville College of Arts and Sciences Chemistry 2320 S. Brook 40208 Louisville UNITED STATES
| | - Teruo Umemoto
- University of Louisville College of Arts and Sciences Chemistry UNITED STATES
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4
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Chen M, Wu ZJ, Song J, Xu HC. Electrocatalytic Allylic C-H Alkylation Enabled by a Dual-Function Cobalt Catalyst. Angew Chem Int Ed Engl 2022; 61:e202115954. [PMID: 35129253 DOI: 10.1002/anie.202115954] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Indexed: 12/11/2022]
Abstract
The direct functionalization of allylic C-H bonds with nucleophiles minimizes pre-functionalization and converts inexpensive, abundantly available materials to value-added alkenyl-substituted products but remains challenging. Here we report an electrocatalytic allylic C-H alkylation reaction with carbon nucleophiles employing an easily available cobalt-salen complex as the molecular catalyst. These C(sp3 )-H/C(sp3 )-H cross-coupling reactions proceed through H2 evolution and require no external chemical oxidants. Importantly, the mild conditions and unique electrocatalytic radical process ensure excellent functional group tolerance and substrate compatibility with both linear and branched terminal alkenes. The synthetic utility of the electrochemical method is highlighted by its scalability (up to 200 mmol scale) under low loading of electrolyte (down to 0.05 equiv) and its successful application in the late-stage functionalization of complex structures.
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Affiliation(s)
- Ming Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Innovative Collaboration Center of Chemistry for Energy Materials, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Zheng-Jian Wu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Innovative Collaboration Center of Chemistry for Energy Materials, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Jinshuai Song
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China
| | - Hai-Chao Xu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Innovative Collaboration Center of Chemistry for Energy Materials, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
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5
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Chen M, Wu Z, Song J, Xu H. Electrocatalytic Allylic C−H Alkylation Enabled by a Dual‐Function Cobalt Catalyst**. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202115954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ming Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces Innovative Collaboration Center of Chemistry for Energy Materials Key Laboratory of Chemical Biology of Fujian Province College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China
| | - Zheng‐Jian Wu
- State Key Laboratory of Physical Chemistry of Solid Surfaces Innovative Collaboration Center of Chemistry for Energy Materials Key Laboratory of Chemical Biology of Fujian Province College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China
| | - Jinshuai Song
- Green Catalysis Center, and College of Chemistry Zhengzhou University Zhengzhou 450001 China
| | - Hai‐Chao Xu
- State Key Laboratory of Physical Chemistry of Solid Surfaces Innovative Collaboration Center of Chemistry for Energy Materials Key Laboratory of Chemical Biology of Fujian Province College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China
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6
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Schäfer G, Fleischer T, Blumer N, Udry M, Reber S, Stansfield I, Liu Y, Li Y, Li P. Initial Route Scouting and Final Process Development for the Multi-Kg Production of 3-Fluoro-6-methoxyquinoline from p-Anisidine and 2-Fluoromalonic Acid. Org Process Res Dev 2022. [DOI: 10.1021/acs.oprd.1c00414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gabriel Schäfer
- Chemistry Process R&D, Idorsia Pharmaceuticals Ltd., Hegenheimermattweg 91, CH-4123 Allschwil, Switzerland
| | - Tony Fleischer
- Chemistry Process R&D, Idorsia Pharmaceuticals Ltd., Hegenheimermattweg 91, CH-4123 Allschwil, Switzerland
| | - Nicole Blumer
- Chemistry Process R&D, Idorsia Pharmaceuticals Ltd., Hegenheimermattweg 91, CH-4123 Allschwil, Switzerland
| | - Megan Udry
- Chemistry Process R&D, Idorsia Pharmaceuticals Ltd., Hegenheimermattweg 91, CH-4123 Allschwil, Switzerland
| | - Stefan Reber
- Chemistry Process R&D, Idorsia Pharmaceuticals Ltd., Hegenheimermattweg 91, CH-4123 Allschwil, Switzerland
| | - Ian Stansfield
- Chiral Quest (Suzhou) Co., Limited, 268 ChangAn Road, Wujiang, Suzhou, Jiangsu 215200, China
| | - Yuanhua Liu
- Chiral Quest (Suzhou) Co., Limited, 268 ChangAn Road, Wujiang, Suzhou, Jiangsu 215200, China
| | - Yan Li
- Chiral Quest (Suzhou) Co., Limited, 268 ChangAn Road, Wujiang, Suzhou, Jiangsu 215200, China
| | - Pixu Li
- Chiral Quest (Suzhou) Co., Limited, 268 ChangAn Road, Wujiang, Suzhou, Jiangsu 215200, China
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7
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Zhang K, Sheng X, Deiana L, Svensson Grape E, Inge K, Himo F, Cordova A. Solvent Dependency in Stereoselective δ‐Lactam Formation of Chiral α‐Fluoromalonate Derivatives: Stereodivergent Synthesis of Heterocycles with Fluorine Containing Quaternary Stereocenters Adjacent to Tertiary Stereocenters. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202101404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kaiheng Zhang
- Mittuniversitetet Fakulteten for naturvetenskap teknik och medier SWEDEN
| | - Xiang Sheng
- Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences CHINA
| | - Luca Deiana
- Stockholms Universitet Naturvetenskapliga fakulteten SWEDEN
| | | | - Ken Inge
- Stockholm University Faculty of Natural Sciences SWEDEN
| | | | - Armando Cordova
- Mittuniversitetet Fakulteten for naturvetenskap teknik och medier SWEDEN
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8
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Bock L, Schultheiß SK, Maschauer S, Lasch R, Gradl S, Prante O, Zard SZ, Heinrich MR. Synthesis of 2‐(Chlorodifluoromethyl)indoles for Nucleophilic Halogen Exchange with [
18
F]Fluoride. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Leonard Bock
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Stefanie K. Schultheiß
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Simone Maschauer
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Schwabachanlage 12 91054 Erlangen Germany
| | - Roman Lasch
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Susanne Gradl
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Olaf Prante
- Department of Nuclear Medicine, Molecular Imaging and Radiochemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Schwabachanlage 12 91054 Erlangen Germany
| | - Samir Z. Zard
- Laboratoire de Synthèse Organique associé au CNRS Ecole Polytechnique 91128 Palaiseau France
| | - Markus R. Heinrich
- Department of Chemistry and Pharmacy, Pharmaceutical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
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9
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Yan SS, Liu SH, Chen L, Bo ZY, Jing K, Gao TY, Yu B, Lan Y, Luo SP, Yu DG. Visible-light photoredox-catalyzed selective carboxylation of C(sp3)−F bonds with CO2. Chem 2021. [DOI: 10.1016/j.chempr.2021.08.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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10
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Heeran D, Murray BJ, Qiu S, Martin SJ, Skelton RM, Dodds KR, Yufit DS, Sandford G. Synthesis of polyfunctional fluoro-quinoline and fluoro-pyridopyrimidinone derivatives. J Fluor Chem 2021. [DOI: 10.1016/j.jfluchem.2021.109830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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11
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Lv Y, Pu W, Zhu X, Chen C, Wang S. Copper-Catalyzed 1,1-Alkylmonofluoroalkylation of Terminal Alkynes with Diazo Compounds and 2-Fluoro-1,3-dicarbonyl Compounds: Access toward ( E)-β-Monofluoroalkyl-β,γ-unsaturated Esters or Ketones. J Org Chem 2021; 86:10043-10054. [PMID: 34313118 DOI: 10.1021/acs.joc.1c00789] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An efficient copper-catalyzed three-component 1,1-alkylmonofluoroalkylation of terminal alkynes, diazo compounds, and 2-fluoro-1,3-dicarbonyl compounds for the synthesis of (E)-β-monofluoroalkyl-β,γ-unsaturated esters or ketones has been developed. The methodology features a broad substrate scope, an inexpensive and easily available catalytic system, and excellent selectivity with good yields. The mechanism of the tandem Cu-catalyzed cross-coupling and nucleophilic addition of allenes has been investigated.
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Affiliation(s)
- Yunhe Lv
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, P. R. China
| | - Weiya Pu
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, P. R. China
| | - Xueli Zhu
- College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Chen Chen
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, P. R. China
| | - Shanshan Wang
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, P. R. China
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12
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Doyle MGJ, Lundgren RJ. Oxidative cross-coupling processes inspired by the Chan-Lam reaction. Chem Commun (Camb) 2021; 57:2724-2731. [PMID: 33623942 DOI: 10.1039/d1cc00213a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The Cu-catalyzed oxidative cross-coupling of N- and O-nucleophiles with aryl boronic acids (the Chan-Lam reaction) remains among the most useful approaches to prepare aniline and phenol derivatives. The combination of high chemoselectivity, mild reaction conditions, and the ability to use simple Cu-salts as catalysts makes this process a valuable alternative to aromatic substitutions and Pd-catalyzed reactions of aryl electrophiles (Buchwald-Hartwig coupling). Despite the widespread use of Chan-Lam reactions in synthesis, the analogous carbon-carbon bond forming variant of this process had not been developed prior to our work. This feature article describes our discovery and application of Cu-catalyzed oxidative coupling reactions of activated methylene derivatives or carboxylic acids with nucleophiles including aryl boronic esters and amines.
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Affiliation(s)
- Michael G J Doyle
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Rylan J Lundgren
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
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13
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Fujihira Y, Liang Y, Ono M, Hirano K, Kagawa T, Shibata N. Synthesis of trifluoromethyl ketones by nucleophilic trifluoromethylation of esters under a fluoroform/KHMDS/triglyme system. Beilstein J Org Chem 2021; 17:431-438. [PMID: 33633811 PMCID: PMC7884878 DOI: 10.3762/bjoc.17.39] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 02/02/2021] [Indexed: 12/29/2022] Open
Abstract
A straightforward method that enables the formation of biologically attractive trifluoromethyl ketones from readily available methyl esters using the potent greenhouse gas fluoroform (HCF3, HFC-23) was developed. The combination of fluoroform and KHMDS in triglyme at −40 °C was effective for this transformation, with good yields as high as 92%. Substrate scope of the trifluoromethylation procedure was explored for aromatic, aliphatic, and conjugated methyl esters. This study presents a straightforward trifluoromethylation process of various methyl esters that convert well to the corresponding trifluoromethyl ketones. The tolerance of various pharmacophores under the reaction conditions was also explored.
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Affiliation(s)
- Yamato Fujihira
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-5888, Japan
| | - Yumeng Liang
- Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-5888, Japan
| | - Makoto Ono
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-5888, Japan
| | - Kazuki Hirano
- Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-5888, Japan
| | - Takumi Kagawa
- Tosoh Finechem Corporation, 4988, Kaiseicho, Shunan, 746-0006, Japan
| | - Norio Shibata
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-5888, Japan.,Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-5888, Japan.,Institute of Advanced Fluorine-Containing Materials, Zhejiang Normal University, 688 Yingbin Avenue, 321004 Jinhua, China
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14
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Rozatian N, Hodgson DRW. Reactivities of electrophilic N-F fluorinating reagents. Chem Commun (Camb) 2021; 57:683-712. [PMID: 33367354 DOI: 10.1039/d0cc06339h] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Electrophilic fluorination represents one of the most direct and useful methods available for the selective introduction of fluorine into organic compounds. Electrophilic fluorinating reagents of the N-F class have revolutionised the incorporation of fluorine atoms into both pharmaceutically- and agrochemically-important substrates. Since the earliest N-F reagents were commercialised in the 1990s, their reactivities have been investigated using qualitative and, more recently, quantitative methods. This review discusses the different experimental approaches employed to determine reactivities of N-F reagents, focussing on the kinetics studies reported in recent years. We make critical evaluations of the experimental approaches against each other, theoretical approaches, and their applicability towards practical problems. The opportunities for achieving more efficient synthetic electrophilic fluorination processes through kinetic understanding are highlighted.
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Affiliation(s)
- Neshat Rozatian
- Chemistry Department, Durham University, South Road, Durham, UKDH1 3LE.
| | - David R W Hodgson
- Chemistry Department, Durham University, South Road, Durham, UKDH1 3LE.
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15
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Li Z, Qiu X, Lou J, Wang Q. Progress in Visible-Light Catalyzed C—F Bond Functionalization of gem-Difluoroalkenes. CHINESE J ORG CHEM 2021. [DOI: 10.6023/cjoc202106013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Chai JY, Cha H, Lee SS, Oh YH, Lee S, Chi DY. Mechanistic study of nucleophilic fluorination for the synthesis of fluorine-18 labeled fluoroform with high molar activity from N-difluoromethyltriazolium triflate. RSC Adv 2021; 11:6099-6106. [PMID: 35423150 PMCID: PMC8694808 DOI: 10.1039/d0ra09827b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 12/18/2020] [Indexed: 12/11/2022] Open
Abstract
The synthesis of fluorine-18 labeled fluoroform with high molar activity has grown in importance for the development of fluorine-18 labeled aryl-CF3 radiopharmaceuticals that are useful as diagnostic radiotracers for the powerful technique of positron emission tomography (PET). We designed a strategy of synthesizing fluorine-18 labeled fluoroform from N1-difluoromethyl-N3-methyltriazolium triflate (1) via SN2 fluorination without stable fluorine isotope scrambling. Fluoroform was generated at rt in 10 min by fluorination of the triazolium precursor with TBAF (6 equiv.). We propose three routes (a), (b), and (c) for this fluorination. Quantum chemical calculations have been carried out to elucidate the mechanism of experimentally observed nucleophilic attack of fluoride at difluoromethyl group via route (a), not N3-methyl via route (b). 1H and 19F NMR studies using deuterium source have been performed to examine the competition between SN2 fluorination (route (a)) and the formation of difluorocarbene (route (c)). The observed superiority of SN2 pathway to formation of difluorocarbene in the reaction of the precursor using CsF in (CD3CN/(CD3)3COD (17.8 : 1)) gives the possibility of preparing the fluorine-18 labeled fluoroform in high molar activity. Route a: desired SN2 reaction of fluoride to form fluoroform with high molar activity; route b: side reaction to form methyl fluoride; route c: side reaction to form difluorocarbene to give fluoroform with lower molar activity.![]()
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Affiliation(s)
- Jin Young Chai
- Department of Chemistry
- Sogang University
- Seoul 04107
- Korea
| | - Hyojin Cha
- Department of Chemistry
- Sogang University
- Seoul 04107
- Korea
| | - Sung-Sik Lee
- Department of Applied Chemistry
- Kyung Hee University
- Yongin-si
- Korea
| | - Young-Ho Oh
- Department of Applied Chemistry
- Kyung Hee University
- Yongin-si
- Korea
| | - Sungyul Lee
- Department of Applied Chemistry
- Kyung Hee University
- Yongin-si
- Korea
| | - Dae Yoon Chi
- Department of Chemistry
- Sogang University
- Seoul 04107
- Korea
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17
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Harsanyi A, Lückener A, Pasztor H, Yilmaz Z, Tam L, Yufit DS, Sandford G. α-Fluorotricarbonyl Derivatives as Versatile Fluorinated Building Blocks: Synthesis of Fluoroacetophenone, Fluoroketo Ester and Fluoropyran-4-one Derivatives. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000503] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Antal Harsanyi
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
| | - Anne Lückener
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
| | - Hedvig Pasztor
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
| | - Zahide Yilmaz
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
| | - Lawrence Tam
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
| | - Dmitry S. Yufit
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
| | - Graham Sandford
- Department of Chemistry; Durham University; South Road DH1 3LE Durham U.K
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18
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Lv Y, Pu W, Wang X. Ligand-free copper-catalyzed regio- and stereoselective 1,1-alkylmonofluoroalkylation of terminal alkynes. Chem Commun (Camb) 2020; 56:12933-12936. [DOI: 10.1039/d0cc05887d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel copper-catalyzed highly regio- and stereoselective 1,1-alkylmonofluoroalkylation of terminal alkynes without an external ligand has been developed.
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Affiliation(s)
- Yunhe Lv
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang
- P. R. China
| | - Weiya Pu
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang
- P. R. China
| | - Xiaoxing Wang
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang
- P. R. China
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19
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Rozatian N, Beeby A, Ashworth IW, Sandford G, Hodgson DRW. Enolization rates control mono- versus di-fluorination of 1,3-dicarbonyl derivatives. Chem Sci 2019; 10:10318-10330. [PMID: 32110319 PMCID: PMC6979503 DOI: 10.1039/c9sc04185k] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 09/16/2019] [Indexed: 12/27/2022] Open
Abstract
All rate constants for fluorination and enolization are determined.
Fluorine-containing 1,3-dicarbonyl derivatives are essential building blocks for drug discovery and manufacture. To understand the factors that determine selectivity between mono- and di-fluorination of 1,3-dicarbonyl systems, we have performed kinetic studies of keto–enol tautomerism and fluorination processes. Photoketonization of 1,3-diaryl-1,3-dicarbonyl derivatives and their 2-fluoro analogues is coupled with relaxation kinetics to determine enolization rates. Reaction additives such as water accelerate enolization processes, especially of 2-fluoro-1,3-dicarbonyl systems. Kinetic studies of enol fluorination with Selectfluor™ and NFSI reveal the quantitative effects of 2-fluorination upon enol nucleophilicity towards reagents of markedly different electrophilicity. Our findings have important implications for the synthesis of α,α-difluoroketonic compounds, providing valuable quantitative information to aid in the design of fluorination and difluorination reactions.
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Affiliation(s)
- Neshat Rozatian
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
| | - Andrew Beeby
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
| | - Ian W Ashworth
- AstraZeneca , Pharmaceutical Technology & Development , Macclesfield , SK10 2NA , UK
| | - Graham Sandford
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
| | - David R W Hodgson
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
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20
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Rozatian N, Ashworth IW, Sandford G, Hodgson DRW. A quantitative reactivity scale for electrophilic fluorinating reagents. Chem Sci 2018; 9:8692-8702. [PMID: 30595834 PMCID: PMC6263395 DOI: 10.1039/c8sc03596b] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 09/13/2018] [Indexed: 11/21/2022] Open
Abstract
Through kinetic studies we provide a quantitative reactivity scale for ten electrophilic fluorination reagents.
Electrophilic N–F fluorination agents underpin the introduction of fluorine in aliphatic systems across drug and academic research. The choice of N–F reagent is currently determined through empirical experimentation in the absence of quantitative values for electrophilicities. Here we report an experimentally-determined kinetic reactivity scale for ten N–F fluorinating reagents, including Selectfluor™, NFSI, Synfluor™ and several N-fluoropyridinium salts, in CH3CN. The reactivity scale, which covers eight orders of magnitude, employs para-substituted 1,3-diaryl-1,3-dicarbonyl derivatives to measure relative and absolute rate constants. The para-substituted 1,3-diaryl-1,3-dicarbonyl scaffold delivers a convenient, sensitive spectrophotometric reporter of reactivity that also led to the discovery of a unique form of tautomeric polymorphism.
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Affiliation(s)
- Neshat Rozatian
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
| | - Ian W Ashworth
- AstraZeneca , Pharmaceutical Technology & Development , Macclesfield , SK10 2NA , UK
| | - Graham Sandford
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
| | - David R W Hodgson
- Chemistry Department , Durham University , South Road , Durham , DH1 3LE , UK .
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21
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Song T, Zhao X, Hu J, Dan W. Diastereoselective and Enantioselective Palladium-Catalyzed Allylic Substitution of Substituted Fluorinated Methylene Derivatives. European J Org Chem 2018. [DOI: 10.1002/ejoc.201701739] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Tao Song
- Shanghai Key Lab of Chemical Assessment and Sustainability; School of Chemical Technology and Engineering; Tongji University; 1239 Siping Road 200092 Shanghai P.R. China
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Sciences; 354 Fenglin Road 200032 Shanghai P R China
| | - Xiaoming Zhao
- Shanghai Key Lab of Chemical Assessment and Sustainability; School of Chemical Technology and Engineering; Tongji University; 1239 Siping Road 200092 Shanghai P.R. China
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Sciences; 354 Fenglin Road 200032 Shanghai P R China
| | - Jiao Hu
- Shanghai Key Lab of Chemical Assessment and Sustainability; School of Chemical Technology and Engineering; Tongji University; 1239 Siping Road 200092 Shanghai P.R. China
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Sciences; 354 Fenglin Road 200032 Shanghai P R China
| | - Wenyan Dan
- Shanghai Key Lab of Chemical Assessment and Sustainability; School of Chemical Technology and Engineering; Tongji University; 1239 Siping Road 200092 Shanghai P.R. China
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Sciences; 354 Fenglin Road 200032 Shanghai P R China
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22
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Synthesis of β-fluoro(dicarbonyl)ethylamines from 2-fluoro-ethylacetoacetate and dimethyl-2-fluoromalonate ester by batch and semi-continuous flow three-component Mannich reactions. J Fluor Chem 2018. [DOI: 10.1016/j.jfluchem.2017.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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23
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Verma S, Baig RBN, Nadagouda MN, Varma RS. Photocatalytic C-H Activation and Oxidative Esterification Using Pd@g-C 3N 4. Catal Today 2018; 309:248-252. [PMID: 31595104 PMCID: PMC6781236 DOI: 10.1016/j.cattod.2017.06.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Graphitic carbon nitride supported palladium nanoparticles, Pd@g-C3N4, have been synthesized and utilized for the direct oxidative esterification of alcohols using atmospheric oxygen as a co-oxidant via photocatalytic C-H activation.
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Affiliation(s)
- Sanny Verma
- Sustainable Technology Division, National Risk Management Research Laboratory, U. S. Environmental Protection Agency, 26 West Martin Luther King Drive, MS 443, Cincinnati, Ohio 45268, USA
| | - R. B. Nasir Baig
- Sustainable Technology Division, National Risk Management Research Laboratory, U. S. Environmental Protection Agency, 26 West Martin Luther King Drive, MS 443, Cincinnati, Ohio 45268, USA
| | - Mallikarjuna N. Nadagouda
- WQMB, WSWRD, National Risk Management Research Laboratory, U. S. Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268, USA
| | - Rajender S. Varma
- Sustainable Technology Division, National Risk Management Research Laboratory, U. S. Environmental Protection Agency, 26 West Martin Luther King Drive, MS 443, Cincinnati, Ohio 45268, USA
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24
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Huang JQ, Nairoukh Z, Marek I. Electrophilic fluorination of stereodefined disubstituted silyl ketene hemiaminals en route to tertiary α-fluorinated carbonyl derivatives. Org Biomol Chem 2018; 16:1079-1082. [DOI: 10.1039/c8ob00067k] [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 highly diastereoselective synthesis of tertiary α-fluoro carbonyl compounds is reported in only two chemical steps from a simple alkyne through the reaction of stereodefined fully substituted silyl ketene hemiaminal derivatives with Selectfluor.
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Affiliation(s)
- Jian Qiang Huang
- The Mallat Family Laboratory of Organic Chemistry
- Schulich Faculty of Chemistry
- Technion-Israel Institute of Technology
- Haifa, 32000
- Israel
| | - Zackaria Nairoukh
- The Mallat Family Laboratory of Organic Chemistry
- Schulich Faculty of Chemistry
- Technion-Israel Institute of Technology
- Haifa, 32000
- Israel
| | - Ilan Marek
- The Mallat Family Laboratory of Organic Chemistry
- Schulich Faculty of Chemistry
- Technion-Israel Institute of Technology
- Haifa, 32000
- Israel
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25
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Szpera R, Kovalenko N, Natarajan K, Paillard N, Linclau B. The synthesis of the 2,3-difluorobutan-1,4-diol diastereomers. Beilstein J Org Chem 2017; 13:2883-2887. [PMID: 30018668 PMCID: PMC5753060 DOI: 10.3762/bjoc.13.280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/13/2017] [Indexed: 12/05/2022] Open
Abstract
The diastereoselective synthesis of fluorinated building blocks that contain chiral fluorine substituents is of interest. Here we describe optimisation efforts in the synthesis of anti-2,3-difluorobutane-1,4-diol, as well as the synthesis of the corresponding syn-diastereomer. Both targets were synthesised using an epoxide opening strategy.
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Affiliation(s)
- Robert Szpera
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Nadia Kovalenko
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Kalaiselvi Natarajan
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Nina Paillard
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Bruno Linclau
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
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26
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Gupta E, Kant R, Mohanan K. Decarbethoxylative Arylation Employing Arynes: A Metal-Free Pathway to Arylfluoroamides. Org Lett 2017; 19:6016-6019. [PMID: 29034681 DOI: 10.1021/acs.orglett.7b03072] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
An efficient, metal-free decarbethoxylative arylation protocol for the synthesis of α-aryl-α-fluoroamides from fluoromalonamates, under ambient reaction conditions using aryne as an electrophilic arylating agent, is reported. This decarbethoxylative arylation proceeds under mild conditions and provides a practical and effective entry to a wide range of α-aryl-α-fluoroacetamides. Interestingly, the use of the tert-butyl ester of fluoromalonamate prevented the otherwise rapid decarboxylation step, affording the arylated fluoromalonamate in moderate yield.
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Affiliation(s)
| | | | - Kishor Mohanan
- Academy of Scientific and Innovative Research , New Delhi 110001, India
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27
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Chen J, Zhao X, Dan W. Diasteroselective and Enantioselective Ir-Catalyzed Allylic Substitutions of 1-Substituted 1-Fluoro-1-(arenesulfonyl)methylene Derivatives. J Org Chem 2017; 82:10693-10698. [DOI: 10.1021/acs.joc.7b01782] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jiteng Chen
- Shanghai
Key Lab of Chemical Assessment and Sustainability, School of Chemical
Technology and Engineering, Tongji University, 1239 Siping Road, 200092 Shanghai, P. R. China
- Key Laboratory of Organofluorine
Chemistry, Shanghai Institute
of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, P. R. China
| | - Xiaoming Zhao
- Shanghai
Key Lab of Chemical Assessment and Sustainability, School of Chemical
Technology and Engineering, Tongji University, 1239 Siping Road, 200092 Shanghai, P. R. China
- Key Laboratory of Organofluorine
Chemistry, Shanghai Institute
of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, P. R. China
| | - Wenyan Dan
- Shanghai
Key Lab of Chemical Assessment and Sustainability, School of Chemical
Technology and Engineering, Tongji University, 1239 Siping Road, 200092 Shanghai, P. R. China
- Key Laboratory of Organofluorine
Chemistry, Shanghai Institute
of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, P. R. China
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28
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Matsunaga S, Fukagawa S, Xu Y, Anada M, Yoshino T. Catalytic Enantioselective Desymmetrization of meso-Aziridines with Fluoromalonates. HETEROCYCLES 2017. [DOI: 10.3987/com-17-13725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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29
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Yang J, Zhou X, Zeng Y, Huang C, Xiao Y, Zhang J. Divergent synthesis from reactions of 2-trifluoromethyl-1,3-conjugated enynes with N-acetylated 2-aminomalonates. Org Biomol Chem 2017; 15:2253-2258. [DOI: 10.1039/c6ob02749k] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Divergent synthesis of fluorinated heterocycles from the reactions of 2-trifluoromethyl-1,3-conjugated enynes with N-acetylated 2-aminomalonates and subsequent gold-catalysed cyclization were developed.
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Affiliation(s)
- Jieru Yang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- P. R. China
| | - Xiaofan Zhou
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- P. R. China
| | - Yu Zeng
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- P. R. China
| | - Chaoqian Huang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- P. R. China
| | - Yuanjing Xiao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- P. R. China
| | - Junliang Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- P. R. China
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30
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Kitamura T. Hypervalent Iodine-Mediated Fluorination: Development of Catalytic and Stoichiometric Fluorination Reactions. J SYN ORG CHEM JPN 2017. [DOI: 10.5059/yukigoseikyokaishi.75.134] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Tsugio Kitamura
- Department of Chemistry and Applied Chemistry, Graduate School of Science and Engineering, Saga University
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31
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Chernykh AV, Feskov IO, Chernykh AV, Daniliuc CG, Tolmachova NA, Volochnyuk DM, Radchenko DS. Synthesis of fluorinated building blocks based on spiro[3.3]heptane scaffold. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.12.081] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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32
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Preshlock S, Tredwell M, Gouverneur V. (18)F-Labeling of Arenes and Heteroarenes for Applications in Positron Emission Tomography. Chem Rev 2016; 116:719-66. [PMID: 26751274 DOI: 10.1021/acs.chemrev.5b00493] [Citation(s) in RCA: 477] [Impact Index Per Article: 59.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Diverse radiochemistry is an essential component of nuclear medicine; this includes imaging techniques such as positron emission tomography (PET). As such, PET can track diseases at an early stage of development, help patient care planning through personalized medicine and support drug discovery programs. Fluorine-18 is the most frequently used radioisotope in PET radiopharmaceuticals for both clinical and preclinical research. Its physical and nuclear characteristics (97% β(+) decay, 109.8 min half-life, 635 keV positron energy) and high specific activity make it an attractive nuclide for labeling and molecular imaging. Arenes and heteroarenes are privileged candidates for (18)F-incorporation as they are metabolically robust and therefore widely used by medicinal chemists and radiochemists alike. For many years, the range of (hetero)arenes amenable to (18)F-fluorination was limited by the lack of chemically diverse precursors, and of radiochemical methods allowing (18)F-incorporation in high selectivity and efficiency (radiochemical yield and purity, specific activity, and radio-scalability). The appearance of late-stage fluorination reactions catalyzed by transition metal or small organic molecules (organocatalysis) has encouraged much research on the use of these activation manifolds for (18)F-fluorination. In this piece, we review all of the reactions known to date to install the (18)F substituent and other key (18)F-motifs (e.g., CF3, CHF2, OCF3, SCF3, OCHF2) of medicinal relevance onto (hetero)arenes. The field has changed significantly in the past five years, and the current trend suggests that the radiochemical space available for PET applications will expand rapidly in the near future.
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Affiliation(s)
- Sean Preshlock
- Chemistry Research Laboratory, University of Oxford , Oxford OX1 3TA, United Kingdom
| | - Matthew Tredwell
- Chemistry Research Laboratory, University of Oxford , Oxford OX1 3TA, United Kingdom
| | - Véronique Gouverneur
- Chemistry Research Laboratory, University of Oxford , Oxford OX1 3TA, United Kingdom
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33
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Ulmer A, Brunner C, Arnold AM, Pöthig A, Gulder T. A Fluorination/Aryl Migration/Cyclization Cascade for the Metal-Free Synthesis of Fluoro-Benzoxazepines. Chemistry 2015; 22:3660-4. [PMID: 26641801 DOI: 10.1002/chem.201504749] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Indexed: 11/09/2022]
Abstract
Fluorinated organic molecules are of high interest for many applications across chemical and medical disciplines. Efficient methods for the synthesis of such compounds are thus needed. Within this work, application of the bench-stable cyclic hypervalent iodine(III) fluoro reagent 1 facilitated the development of an efficient, metal-free method for the preparation of the novel class of 4-fluoro-1,3-benzoxazepines starting from readily available styrenes. The efficacy and broad applicability of this concept is demonstrated by the synthesis of 20 structurally diverse congeners in high yields, regio-, and diastereoselectivities. The presented method provides complementary chemoselectivity when compared to the common, commercially available electrophilic fluorination reagents, such as selectfluor. First mechanistic investigations with isotopically labeled substrates reveal a complex reaction mechanism, proceeding via an unusual fluorination/1,2-aryl migration/cyclization cascade.
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Affiliation(s)
- Anna Ulmer
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Christoph Brunner
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Andreas M Arnold
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Alexander Pöthig
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Tanja Gulder
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany.
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34
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Zhu F, Xu PW, Zhou F, Wang CH, Zhou J. Recycle Waste Salt as Reagent: A One-Pot Substitution/Krapcho Reaction Sequence to α-Fluorinated Esters and Sulfones. Org Lett 2015; 17:972-5. [DOI: 10.1021/acs.orglett.5b00072] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Feng Zhu
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, Department
of Chemistry, East China Normal University, Shanghai 200062, P. R. China
| | - Peng-Wei Xu
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, Department
of Chemistry, East China Normal University, Shanghai 200062, P. R. China
| | - Feng Zhou
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, Department
of Chemistry, East China Normal University, Shanghai 200062, P. R. China
| | - Cui-Hong Wang
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, Department
of Chemistry, East China Normal University, Shanghai 200062, P. R. China
| | - Jian Zhou
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, Department
of Chemistry, East China Normal University, Shanghai 200062, P. R. China
- State
Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin 300071, P. R. China
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