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Li BJ, Ruan YL, Zhu L, Zhou J, Yu JS. Recent advances in catalytic enantioselective construction of monofluoromethyl-substituted stereocenters. Chem Commun (Camb) 2024. [PMID: 39240236 DOI: 10.1039/d4cc03788j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2024]
Abstract
Chiral organofluorine compounds featuring a monofluoromethyl (CH2F)-substituted stereocenter are often encountered in a number of drugs and bioactive molecules. Consequently, the development of catalytic asymmetric methods for the enantioselective construction of CH2F-substituted stereocenters has made great progress over the past two decades, and a variety of enantioselective transformations have been accordingly established. According to the types of fluorinated reagents or substrates employed, these protocols can be divided into the following major categories: (i) enantioselective ring opening of epoxides or azetidinium salts by fluoride anions; (ii) asymmetric monofluoromethylation with 1-fluorobis(phenylsulfonyl)methane; (iii) asymmetric fluorocyclization of functionalized alkenes with Selectfluor; and (iv) asymmetric transformations involving α-CH2F ketones, α-CH2F alkenes, or other CH2F-containing substrates. This feature article aims to summarize these recent advances and discusses the possible reaction mechanisms, advantages and limitations of each protocol and their applications. Synthetic opportunities still open for further development are illustrated as well. This review article will be an inspiration for researchers engaged in asymmetric catalysis, organofluorine chemistry, and medicinal chemistry.
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Affiliation(s)
- Bo-Jie Li
- Hubei Engineering University, Xiaogan, China.
| | - Yu-Long Ruan
- State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development; School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China.
| | - Lei Zhu
- Hubei Engineering University, Xiaogan, China.
| | - Jian Zhou
- State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development; School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China.
| | - Jin-Sheng Yu
- State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development; School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, P. R. China.
- Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, Hainan Normal University, Haikou 571158, P. R. China
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Haufe G. Selective Synthesis of Monofluorinated Compounds Applying Amine/HF Reagents. CHEM REC 2023; 23:e202300140. [PMID: 37229773 DOI: 10.1002/tcr.202300140] [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: 04/17/2023] [Revised: 05/09/2023] [Indexed: 05/27/2023]
Abstract
For nucleophilic monofluorination, amine/HF reagents such as Et3 N⋅3HF, Pyr⋅9HF (Olah's reagent) and similar combinations belong to the most frequently used fluoride sources, whereupon the selectivity of these reagents can be very different depending of its acidity, the nucleophilicity of the fluoride equivalent, and the structure of the particular substrate. These reagents can be used safely in ordinary chemistry laboratories for nucleophilic substitution reactions by fluoride at sp3 -hybridized carbon centers. For ring opening reactions of epoxides, the regio- and stereoselectivity is very much depending of the nature of the epoxide and the acidity of the HF reagent favoring either SN 1 or SN 2 type reactions. Similarly, the outcome of halofluorination and similar reactions with sulfur or seleno electrophiles can be controlled by the particular combination of the electrophile and the fluoride source. Examples for the application of these reaction types for the synthesis of fluorine-containing analogues of natural products or biologically relevant compounds are in the focus of this personal account.
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Affiliation(s)
- Günter Haufe
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, D-48149, Münster, Germany
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Affiliation(s)
- Muniappan Thirumalaikumar
- Department of Applied Chemistry, Sri Venkateswara College of Engineering, Pennalur, Tamil Nadu, India
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Ajenjo J, Destro G, Cornelissen B, Gouverneur V. Closing the gap between 19F and 18F chemistry. EJNMMI Radiopharm Chem 2021; 6:33. [PMID: 34564781 PMCID: PMC8464544 DOI: 10.1186/s41181-021-00143-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/03/2021] [Indexed: 11/10/2022] Open
Abstract
Positron emission tomography (PET) has become an invaluable tool for drug discovery and diagnosis. The positron-emitting radionuclide fluorine-18 is frequently used in PET radiopharmaceuticals due to its advantageous characteristics; hence, methods streamlining access to 18F-labelled radiotracers can make a direct impact in medicine. For many years, access to 18F-labelled radiotracers was limited by the paucity of methodologies available, and the poor diversity of precursors amenable to 18F-incorporation. During the last two decades, 18F-radiochemistry has progressed at a fast pace with the appearance of numerous methodologies for late-stage 18F-incorporation onto complex molecules from a range of readily available precursors including those that do not require pre-functionalisation. Key to these advances is the inclusion of new activation modes to facilitate 18F-incorporation. Specifically, new advances in late-stage 19F-fluorination under transition metal catalysis, photoredox catalysis, and organocatalysis combined with the availability of novel 18F-labelled fluorination reagents have enabled the invention of novel processes for 18F-incorporation onto complex (bio)molecules. This review describes these major breakthroughs with a focus on methodologies for C-18F bond formation. This reinvigorated interest in 18F-radiochemistry that we have witnessed in recent years has made a direct impact on 19F-chemistry with many laboratories refocusing their efforts on the development of methods using nucleophilic fluoride instead of fluorination reagents derived from molecular fluorine gas.
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Affiliation(s)
- Javier Ajenjo
- Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Gianluca Destro
- Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, OX3 7DQ, UK
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK
| | - Bart Cornelissen
- Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Véronique Gouverneur
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
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Zhu W, Zhen X, Wu J, Cheng Y, An J, Ma X, Liu J, Qin Y, Zhu H, Xue J, Jiang X. Catalytic asymmetric nucleophilic fluorination using BF 3·Et 2O as fluorine source and activating reagent. Nat Commun 2021; 12:3957. [PMID: 34172752 PMCID: PMC8233348 DOI: 10.1038/s41467-021-24278-3] [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] [Received: 12/30/2020] [Accepted: 06/09/2021] [Indexed: 01/16/2023] Open
Abstract
Fluorination using chiral catalytic methods could result in a direct access to asymmetric fluorine chemistry. However, challenges in catalytic asymmetric fluorinations, especially the longstanding stereochemical challenges existed in BF3·Et2O-based fluorinations, have not yet been addressed. Here we report the catalytic asymmetric nucleophilic fluorination using BF3·Et2O as the fluorine reagent in the presence of chiral iodine catalyst. Various chiral fluorinated oxazine products were obtained with good to excellent enantioselectivities (up to >99% ee) and diastereoselectivities (up to >20:1 dr). Control experiments (the desired fluoro-oxazines could not be obtained when Py·HF or Et3N·3HF were employed as the fluorine source) indicated that BF3·Et2O acted not only as a fluorine reagent but also as the activating reagent for activation of iodosylbenzene. Catalytic asymmetric fluorination remains elusive, especially the longstanding stereochemical challenges which exist in BF3Et2O-based fluorinations. Here the authors show a catalytic asymmetric nucleophilic fluorination using BF3·Et2O as the fluorine reagent in the presence of chiral iodine catalyst.
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Affiliation(s)
- Weiwei Zhu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Xiang Zhen
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Jingyuan Wu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Yaping Cheng
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Junkai An
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Xingyu Ma
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Jikun Liu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Yuji Qin
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Hao Zhu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Jijun Xue
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Xianxing Jiang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China.
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Abstract
The asymmetric ring-opening of epoxides is an important reaction in organic synthesis, since it allows for the enantioselective installation of two vicinal functional groups with specific stereochemistry within one step from a highly available starting material. An effective class of catalysts for the asymmetric ring-opening of epoxides is metal–salen complexes. This review summarizes the development of metal–salen catalyzed enantioselective desymmetrization of meso-epoxides and kinetic resolution of epoxides with various nucleophiles, including the design and application of both homogeneous- and heterogeneous epoxide-opening catalysts as well as multi-metallic covalent and supramolecular catalytic systems.
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Guo P, Li Y, Zhang XG, Han JF, Yu Y, Zhu J, Ye KY. Redox Neutral Radical-Relay Cobalt Catalysis toward C-H Fluorination and Amination. Org Lett 2020; 22:3601-3606. [PMID: 32307998 DOI: 10.1021/acs.orglett.0c01072] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A redox neutral radical-relay cobalt-catalyzed intramolecular C-H fluorination of N-fluoroamides featuring the in situ formed cobalt fluorides as the latent radical fluorinating agents is reported. Moreover, the reactivity of such a cobalt catalysis could be diverted from C-H fluorination to amination by engineering substrates' conformational flexibility. Preliminary mechanistic studies (UV-vis spectroscopy, cyclic voltammetry studies and DFT calculations, etc.) support the reaction proceeding a redox neutral radical-relay mechanism.
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Affiliation(s)
- Peng Guo
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou 350108, China
| | - Yuanyuan Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xiang-Gui Zhang
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou 350108, China
| | - Jun-Fa Han
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou 350108, China
| | - Yi Yu
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou 350108, China
| | - Jun Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Ke-Yin Ye
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou 350108, China
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8
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Remete AM, Kiss L. Synthesis of Fluorine-Containing Molecular Entities Through Fluoride Ring Opening of Oxiranes and Aziridines. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900981] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Attila Márió Remete
- Institute of Pharmaceutical Chemistry; University of Szeged; Eötvös u. 6 6720 Szeged Hungary
- Interdisciplinary Excellence Centre; Institute of Pharmaceutical Chemistry; University of Szeged; Eötvös u. 6 6720 Szeged Hungary
| | - Loránd Kiss
- Institute of Pharmaceutical Chemistry; University of Szeged; Eötvös u. 6 6720 Szeged Hungary
- Interdisciplinary Excellence Centre; Institute of Pharmaceutical Chemistry; University of Szeged; Eötvös u. 6 6720 Szeged Hungary
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9
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Hou H, Li H, Xu Y, Tang D, Han Y, Yan C, Chen X, Zhu S. Catalyst-free fluorinative alkoxylation of alkenes. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.09.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Abstract
A catalytic ring-opening reaction of epoxides by nucleophilic trifluoromethoxylation of trifluoromethyl arylsulfonate has been developed based on the use of a cobalt catalyst. This reaction provides an efficient, simple route for directly construction of a wide range of vicinal trifluoromethoxyhydrins under mild conditions. In addition, this method can convert terminal epoxides into target products with good chemo- and regioselectivity.
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Affiliation(s)
- Jie Liu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Yongliang Wei
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China.,Collaborative Innovation Center of Chemical Science and Engineering , Tianjin 300071 , China
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11
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Hajra S, Hazra A, Mandal P. Stereocontrolled Nucleophilic Fluorination at the Tertiary sp3-Carbon Center for Enantiopure Synthesis of 3-Fluorooxindoles. Org Lett 2018; 20:6471-6475. [DOI: 10.1021/acs.orglett.8b02777] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Saumen Hajra
- Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, India
| | - Atanu Hazra
- Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, India
| | - Paltu Mandal
- Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, India
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12
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Ponra S, Rabten W, Yang J, Wu H, Kerdphon S, Andersson PG. Diastereo- and Enantioselective Synthesis of Fluorine Motifs with Two Contiguous Stereogenic Centers. J Am Chem Soc 2018; 140:13878-13883. [DOI: 10.1021/jacs.8b08778] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sudipta Ponra
- Department of Organic Chemistry, Stockholm University, Svante Arrhenius väg 16C, SE-10691 Stockholm, Sweden
| | - Wangchuk Rabten
- Department of Organic Chemistry, Stockholm University, Svante Arrhenius väg 16C, SE-10691 Stockholm, Sweden
| | - Jianping Yang
- Department of Organic Chemistry, Stockholm University, Svante Arrhenius väg 16C, SE-10691 Stockholm, Sweden
| | - Haibo Wu
- Department of Organic Chemistry, Stockholm University, Svante Arrhenius väg 16C, SE-10691 Stockholm, Sweden
| | - Sutthichat Kerdphon
- Department of Organic Chemistry, Stockholm University, Svante Arrhenius väg 16C, SE-10691 Stockholm, Sweden
| | - Pher G. Andersson
- Department of Organic Chemistry, Stockholm University, Svante Arrhenius väg 16C, SE-10691 Stockholm, Sweden
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Sedgwick DM, López I, Román R, Kobayashi N, Okoromoba OE, Xu B, Hammond GB, Barrio P, Fustero S. Metal-Free and User-Friendly Regioselective Hydroxyfluorination of Olefins. Org Lett 2018; 20:2338-2341. [PMID: 29624064 PMCID: PMC6237092 DOI: 10.1021/acs.orglett.8b00681] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A simple, user-friendly, metal-free protocol for the regioselective anti-Markovnikov hydrofluorination of olefins using readily available and inexpensive reagents has been developed. This new approach displays a broader scope than previously reported methodologies and has been applied to the late-stage fluorination of a complex molecule, giving rise to a fluorosteroid derivative. The stereochemistry of the process has also been studied in some detail.
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Affiliation(s)
- Daniel M. Sedgwick
- Departamento de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain
- Laboratorio de Moléculas Orgánicas, Centro de Investigación Príncipe Felipe, E-46012 Valencia, Spain
| | - Inés López
- Departamento de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain
| | - Raquel Román
- Laboratorio de Moléculas Orgánicas, Centro de Investigación Príncipe Felipe, E-46012 Valencia, Spain
| | - Nanako Kobayashi
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Otome E. Okoromoba
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40292, United States
| | - Bo Xu
- College of Chemistry, Chemical Engineering and Biotechnology Donghua University Shanghai 201620 (China)
| | - Gerald B. Hammond
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40292, United States
| | - Pablo Barrio
- Departamento de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain
| | - Santos Fustero
- Departamento de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain
- Laboratorio de Moléculas Orgánicas, Centro de Investigación Príncipe Felipe, E-46012 Valencia, Spain
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Sharma A, Agarwal J, Peddinti RK. Direct access to the optically active VAChT inhibitor vesamicol and its analogues via the asymmetric aminolysis of meso-epoxides with secondary aliphatic amines. Org Biomol Chem 2018; 15:1913-1920. [PMID: 28169381 DOI: 10.1039/c6ob02479c] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
First highly enantioselective synthesis of biologically important vesamicol, benzovesamicol, and their derivatives was achieved via the desymmetrization of meso-epoxides with secondary aliphatic amines (4-phenylpiperidine derivatives) using a chiral [salenCo(iii)-BF4] catalyst at room temperature. All products were obtained in good yield and with excellent optical induction.
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Affiliation(s)
- Arun Sharma
- Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Jyoti Agarwal
- Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
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Remete AM, Nonn M, Fustero S, Fülöp F, Kiss L. A Stereocontrolled Protocol to Highly Functionalized Fluorinated Scaffolds through a Fluoride Opening of Oxiranes. Molecules 2016; 21:molecules21111493. [PMID: 27869692 PMCID: PMC6274065 DOI: 10.3390/molecules21111493] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 09/19/2016] [Accepted: 11/04/2016] [Indexed: 11/18/2022] Open
Abstract
A novel selective and substrate-dependent synthetic protocol has been developed towards the synthesis of various fluorine-containing, highly functionalized cycloalkane derivatives. The method involves the stereoselective epoxidation of some unsaturated cyclic β-amino acid derivatives as model compounds, followed by a regioselective fluoride opening of oxiranes under various conditions with Deoxofluor and XtalFluor-E reagents, thereby offering an insight into this new epoxide opening methodology with fluoride.
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Affiliation(s)
- Attila Márió Remete
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
| | - Melinda Nonn
- MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, Eötvös u. 6, H-6720 Szeged, Hungary.
| | - Santos Fustero
- Departamento de Química Orgánica, Facultad de Farmacia, Universidad de Valencia, Av. Vicente Andrés Estellés, s/n 46100 Valencia, Spain.
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, Eötvös u. 6, H-6720 Szeged, Hungary.
| | - Loránd Kiss
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
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Buckingham F, Gouverneur V. Asymmetric 18F-fluorination for applications in positron emission tomography. Chem Sci 2016; 7:1645-1652. [PMID: 28808536 PMCID: PMC5535067 DOI: 10.1039/c5sc04229a] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/12/2015] [Indexed: 01/13/2023] Open
Abstract
Positron emission tomography (PET) is becoming more frequently used by medicinal chemists to facilitate the selection of the most promising lead compounds for further evaluation. For PET, this entails the preparation of 11C- or 18F-labeled drugs or radioligands. With the importance of chirality and fluorine substitution in drug development, chemists can be faced with the challenge of preparing enantiopure molecules featuring the 18F-tag on a stereogenic carbon. Asymmetric 18F-fluorination is an emerging field of research that provides an alternative to resolution or conventional SN2-based radiochemistry. To date, both transition metal complexes and organomediators have been successfully employed for 18F-incorporation at a stereogenic carbon.
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Affiliation(s)
- Faye Buckingham
- University of Oxford , Chemistry Research Laboratory , 12 Mansfield Road , OX1 3UQ , Oxford , UK .
| | - Véronique Gouverneur
- University of Oxford , Chemistry Research Laboratory , 12 Mansfield Road , OX1 3UQ , Oxford , UK .
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18
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Ueta Y, Mikami K, Ito S. Chemical Detection of Hydrogen Fluoride by the Phosphorus Congener of Cyclobutane-1,3-diyl. Inorg Chem 2015; 54:8778-85. [PMID: 26313533 DOI: 10.1021/acs.inorgchem.5b01399] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Heteroaryl-substituted air-tolerant 2,4-bis(2,4,6-tri-t-butylphenyl)-1,3-diphosphacyclobutane-2,4-diyls in the open-shell singlet state were synthesized by a sterically promoted regioselective S(N)Ar process. Here we demonstrate that these diyls are effective for capturing hydrogen fluoride (HF) generated by intermediary base-coordinated HF and amine-stabilized HF reagents. The hydrofluorination reaction predominantly occurred on the λ(3)σ(3)-phosphorus atoms to afford the energetically disfavored 1λ(5),3λ(5)-diphosphete. The positively charged t-butyl-substituted phosphorus atom trapped the fluoride anion, and the subsequent protonation was controlled by the steric effect. X-ray crystallographic analysis and an Atoms in Molecule study of the air-stable 1λ(5),3λ(5)-diphosphete bearing P-H and P-F bonds revealed that the delocalized ylidic linkages in the four-membered ring were almost identical, in contrast to the nonsymmetrically substituted 2,4-bis(2,4,6-tri-t-butylphenyl)-1,3-diphosphacyclobutane-2,4-diyl. Hydrofluorination efficiently induced a remarkable exchange of visible photoabsorption. The charge-transfer-type transition from highest occupied molecular orbital to lowest unoccupied molecular orbital was highly tuned, which is advantageous for the facile identification of HF. In contrast to hitherto known trapping reagents for HF based on cleavage of the H-F bond, several hydrofluorinated P-heterocycles were reconverted into the 1,3-diphosphacyclobutane-2,4-diyl by treatment with sodium hydride. However, in the hydrofluorination of the benzoyl-substituted 1,3-diphosphacyclobutane-2,4-diyl, fluorination and protonation occurred at the t-butyl-substituted phosphorus atom and the skeletal carbon atom, respectively, and the energetically preferable 1λ(5),3λ(3)-dihydrodiphosphete was isolated as a purple-blue crystalline compound. These findings are promising not only for the practical detection of HF but also for the development of fluorine technology based on the chemistry of phosphorus heterocycles.
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Affiliation(s)
- Yasuhiro Ueta
- Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1, Ookayama, Meguro, Tokyo 152-8552, Japan
| | - Koichi Mikami
- Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1, Ookayama, Meguro, Tokyo 152-8552, Japan
| | - Shigekazu Ito
- Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1, Ookayama, Meguro, Tokyo 152-8552, Japan
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19
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Pinacolatoboron fluoride (pinBF) is an efficient fluoride transfer agent for diastereoselective synthesis of benzylic fluorides. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2014.12.044] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Abstract
Fluoroorganic compounds have attracted significant attention in various fields, such as pharmaceutical, agricultural chemistry, and materials science, as a result of their unique physical, chemical, and physiological properties. Consequently, extensive efforts have been devoted to the site-specific synthesis of organofluorine compounds. In recent years, transition-metal-mediated C-F bond formation has emerged as a powerful method for fabrication of these compounds. this Perspective mainly focuses on the most recent advances in transition-metal-assisted synthesis of alkyl fluorides.
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Affiliation(s)
- Xiaoxi Lin
- Department of Chemistry, Fuzhou University, Fuzhou, China350108.
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21
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Yang X, Wu T, Phipps R, Toste FD. Advances in catalytic enantioselective fluorination, mono-, di-, and trifluoromethylation, and trifluoromethylthiolation reactions. Chem Rev 2015; 115:826-70. [PMID: 25337896 PMCID: PMC4311656 DOI: 10.1021/cr500277b] [Citation(s) in RCA: 1084] [Impact Index Per Article: 120.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Indexed: 12/18/2022]
Affiliation(s)
| | | | | | - F. Dean Toste
- Department of Chemistry, University
of California, Berkeley, California 94720, United States
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22
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Fustero S, Simón-Fuentes A, Barrio P, Haufe G. Olefin Metathesis Reactions with Fluorinated Substrates, Catalysts, and Solvents. Chem Rev 2014; 115:871-930. [DOI: 10.1021/cr500182a] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Santos Fustero
- Departamento
de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain
- Laboratorio
de Moléculas Orgánicas, Centro de Investigación Príncipe Felipe, E-46012 Valencia, Spain
| | | | - Pablo Barrio
- Departamento
de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain
| | - Günter Haufe
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, D-48149 Münster, Germany
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23
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24
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Lu DF, Liu GS, Zhu CL, Yuan B, Xu H. Iron(II)-Catalyzed Intramolecular Olefin Aminofluorination. Org Lett 2014; 16:2912-5. [DOI: 10.1021/ol501051p] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Deng-Fu Lu
- Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States
| | - Guan-Sai Liu
- Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States
| | - Cheng-Liang Zhu
- Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States
| | - Bo Yuan
- Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States
| | - Hao Xu
- Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States
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25
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Zhang Q, Nguyen HM. Rhodium-catalyzed regioselective opening of vinyl epoxides with Et3N·3HF reagent – formation of allylic fluorohydrins. Chem Sci 2014. [DOI: 10.1039/c3sc51949j] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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26
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Shen X, Miao W, Ni C, Hu J. Stereoselective Nucleophilic Fluoromethylation of Aryl Ketones: Dynamic Kinetic Resolution of Chiral α-Fluoro Carbanions. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201308484] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Shen X, Miao W, Ni C, Hu J. Stereoselective nucleophilic fluoromethylation of aryl ketones: dynamic kinetic resolution of chiral α-fluoro carbanions. Angew Chem Int Ed Engl 2013; 53:775-9. [PMID: 24307659 DOI: 10.1002/anie.201308484] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Indexed: 02/06/2023]
Abstract
Although many methods are available for the synthesis of optically enriched monofluoromethyl secondary alcohols, synthesizing optically enriched monofluoromethyl tertiary alcohols remains a challenge. An efficient and easy-to-handle nucleophilic fluoromethylation protocol was developed. The current monofluoromethylation showed much higher facial selectivity than the corresponding difluoromethylation and proceeded via a different type of transition state. Excellent stereoselective control at the fluorinated carbon chiral center was found, an effect believed to be facilitated by the dynamic kinetic resolution of the chiral α-fluoro carbanions.
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Affiliation(s)
- Xiao Shen
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032 (China) http://hujinbo.sioc.ac.cn/en/
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28
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Co(salen)-mediated enantioselective radiofluorination of epoxides. Radiosynthesis of enantiomerically enriched [18F]F-MISO via kinetic resolution. J Fluor Chem 2013. [DOI: 10.1016/j.jfluchem.2013.09.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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29
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Abstract
The first catalytic allylic C-H fluorination reaction using a nucleophilic fluoride source is reported. Under the influence of a Pd/Cr cocatalyst system, simple olefin substrates undergo fluorination with Et3N·3HF in good yields with high branched:linear regioselectivity. The mild conditions and broad scope make this reaction a powerful alternative to established methods for the preparation of allylic fluorides from prefunctionalized substrates.
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Affiliation(s)
- Marie-Gabrielle Braun
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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30
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Liang T, Neumann CN, Ritter T. Introduction of fluorine and fluorine-containing functional groups. Angew Chem Int Ed Engl 2013; 52:8214-64. [PMID: 23873766 DOI: 10.1002/anie.201206566] [Citation(s) in RCA: 1965] [Impact Index Per Article: 178.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Indexed: 01/20/2023]
Abstract
Over the past decade, the most significant, conceptual advances in the field of fluorination were enabled most prominently by organo- and transition-metal catalysis. The most challenging transformation remains the formation of the parent C-F bond, primarily as a consequence of the high hydration energy of fluoride, strong metal-fluorine bonds, and highly polarized bonds to fluorine. Most fluorination reactions still lack generality, predictability, and cost-efficiency. Despite all current limitations, modern fluorination methods have made fluorinated molecules more readily available than ever before and have begun to have an impact on research areas that do not require large amounts of material, such as drug discovery and positron emission tomography. This Review gives a brief summary of conventional fluorination reactions, including those reactions that introduce fluorinated functional groups, and focuses on modern developments in the field.
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Affiliation(s)
- Theresa Liang
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
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31
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32
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Kotani S, Furusho H, Sugiura M, Nakajima M. Facile synthesis of chiral 1,2-chlorohydrins via the ring-opening of meso-epoxides catalyzed by chiral phosphine oxides. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.01.066] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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33
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Steward KM, Corbett MT, Goodman CG, Johnson JS. Asymmetric synthesis of diverse glycolic acid scaffolds via dynamic kinetic resolution of α-keto esters. J Am Chem Soc 2012; 134:20197-206. [PMID: 23186551 PMCID: PMC3533366 DOI: 10.1021/ja3102709] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The dynamic kinetic resolution of α-keto esters via asymmetric transfer hydrogenation has been developed as a technique for the highly stereoselective construction of structurally diverse β-substituted-α-hydroxy carboxylic acid derivatives. Through the development of a privileged m-terphenylsulfonamide for (arene)RuCl(monosulfonamide) complexes with a high affinity for selective α-keto ester reduction, excellent levels of chemo-, diastereo-, and enantiocontrol can be realized in the reduction of β-aryl- and β-chloro-α-keto esters.
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Affiliation(s)
| | | | - C. Guy Goodman
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-3290, United States
| | - Jeffrey S. Johnson
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-3290, United States
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34
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Zhu J, Tsui GC, Lautens M. Rhodium-Catalyzed Enantioselective Nucleophilic Fluorination: Ring Opening of Oxabicyclic Alkenes. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201207356] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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35
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Zhu J, Tsui GC, Lautens M. Rhodium-Catalyzed Enantioselective Nucleophilic Fluorination: Ring Opening of Oxabicyclic Alkenes. Angew Chem Int Ed Engl 2012; 51:12353-6. [PMID: 23124934 DOI: 10.1002/anie.201207356] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Indexed: 11/10/2022]
Affiliation(s)
- Jiangtao Zhu
- Davenport Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, M5S 3H6, Canada
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36
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Lauer AM, Wu J. Palladium-catalyzed allylic fluorination of cinnamyl phosphorothioate esters. Org Lett 2012; 14:5138-41. [PMID: 22998123 DOI: 10.1021/ol302263m] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A highly regioselective, Pd-catalyzed allylic fluorination of phosphorothioate esters is reported. This chemistry addresses several limitations of previously reported methods in which elimination and lack of reactivity were problematic. Preliminary mechanistic investigations reveal that these reactions are stereospecific and provide fluorinated products with net retention of stereochemical configuration. In analogy to other Pd-catalyzed allylic substitution reactions, this process likely proceeds through a palladium π-allyl intermediate.
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Affiliation(s)
- Andrew M Lauer
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, USA
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37
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Honjo T, Phipps RJ, Rauniyar V, Toste FD. A Doubly Axially Chiral Phosphoric Acid Catalyst for the Asymmetric Tandem Oxyfluorination of Enamides. Angew Chem Int Ed Engl 2012; 51:9684-8. [DOI: 10.1002/anie.201205383] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Indexed: 01/29/2023]
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38
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Honjo T, Phipps RJ, Rauniyar V, Toste FD. A Doubly Axially Chiral Phosphoric Acid Catalyst for the Asymmetric Tandem Oxyfluorination of Enamides. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201205383] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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39
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Arroyo Y, Sanz-Tejedor MA, Parra A, García Ruano JL. Asymmetric Nucleophilic Monofluorobenzylation of Carbonyl Compounds: Synthesis of Enantiopure vic-Fluorohydrins and α-Fluorobenzylketones. Chemistry 2012; 18:5314-8. [DOI: 10.1002/chem.201103919] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Indexed: 11/11/2022]
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40
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Hu X, Gao B, Chu Y, Li W, Liu X, Lin L, Feng X. Enantioselective Synthesis of β-Pyrazole-Substituted Alcohols through an Asymmetric Ring-Opening Reaction of meso-Epoxides. Chemistry 2012; 18:3473-7. [DOI: 10.1002/chem.201103792] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Indexed: 01/19/2023]
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41
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Hollingworth C, Gouverneur V. Transition metal catalysis and nucleophilic fluorination. Chem Commun (Camb) 2012; 48:2929-42. [PMID: 22334339 DOI: 10.1039/c2cc16158c] [Citation(s) in RCA: 318] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Transition metal catalyzed transformations using fluorinating reagents have been developed extensively for the preparation of synthetically valuable fluorinated targets. This is a topic of critical importance to facilitate laboratory and industrial chemical synthesis of fluorine containing pharmaceuticals and agrochemicals. Translation to (18)F-radiochemistry is also emerging as a vibrant research field because functional imaging based on Positron Emission Tomography (PET) is increasingly used for both diagnosis and pharmaceutical development. This review summarizes how fluoride sources have been used for the catalytic nucleophilic fluorination of various substrates inclusive of aryl triflates, alkynes, allylic halides, allylic esters, allylic trichloroacetimidates, benzylic halides, tertiary alkyl halides and epoxides. Until recently, progress in this field of research has been slow in part because of the challenges associated with the dual reactivity profile of fluoride (nucleophile or base). Despite these difficulties, some remarkable breakthroughs have emerged. This includes the demonstration that Pd(0)/Pd(II)-catalyzed nucleophilic fluorination to access fluoroarenes from aryl triflates is feasible, and the first examples of Tsuji-Trost allylic alkylation with fluoride using either allyl chlorides or allyl precursors bearing O-leaving groups. More recently, allylic fluorides were also made accessible under iridium catalysis. Another reaction, which has been greatly improved based on careful mechanistic work, is the catalytic asymmetric hydrofluorination of meso epoxides. Notably, each individual transition metal catalyzed nucleophilic fluorination reported to date employs a different F-reagent, an observation indicating that this area of research will benefit from a larger pool of nucleophilic fluoride sources. In this context, a striking recent development is the successful design, synthesis and applications of a fluoride-derived electrophilic late stage fluorination reagent. This new class of reagents could greatly benefit preclinical and clinical PET imaging.
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Affiliation(s)
- Charlotte Hollingworth
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA, Oxford, UK
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42
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Hintermann L, Perseghini M, Togni A. Development of the titanium-TADDOLate-catalyzed asymmetric fluorination of β-ketoesters. Beilstein J Org Chem 2011; 7:1421-35. [PMID: 22043253 PMCID: PMC3201056 DOI: 10.3762/bjoc.7.166] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Accepted: 09/19/2011] [Indexed: 11/23/2022] Open
Abstract
Titanium-based Lewis acids catalyze the α-fluorination of β-ketoesters by electrophilic N–F-fluorinating reagents. Asymmetric catalysis with TADDOLato–titanium(IV) dichloride (TADDOL = α,α,α',α'-tetraaryl-(1,3-dioxolane-4,5-diyl)-dimethanol) Lewis acids produces enantiomerically enriched α-fluorinated β-ketoesters in up to 91% enantiomeric excess, with either F–TEDA (1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)) in acetonitrile solution or NFSI (N-fluorobenzenesulfonimide) in dichloromethane solution as fluorinating reagents. The effects of various reaction parameters and of the TADDOL ligand structure on the catalytic activity and enantioselectivity were investigated. The absolute configuration of several fluorination products was assigned through correlation. Evidence for ionization of the catalyst complex by chloride dissociation, followed by generation of titanium β-ketoenolates as key reaction intermediates, was obtained. Based on the experimental findings, a general mechanistic sketch and a steric model of induction are proposed.
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Affiliation(s)
- Lukas Hintermann
- Laboratorium für Anorganische Chemie, ETH Zürich, Wolfgang-Pauli-Str. 10, 8093 Zürich, Switzerland
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43
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Kalow JA, Doyle AG. Mechanistic investigations of cooperative catalysis in the enantioselective fluorination of epoxides. J Am Chem Soc 2011; 133:16001-12. [PMID: 21863842 DOI: 10.1021/ja207256s] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
This report describes mechanistic studies of the (salen)Co- and amine-cocatalyzed enantioselective ring opening of epoxides by fluoride. The kinetics of the reaction, as determined by in situ (19)F NMR analysis, are characterized by apparent first-order dependence on (salen)Co. Substituent effects, nonlinear effects, and reactivity with a linked (salen)Co catalyst provide evidence for a rate-limiting, bimetallic ring-opening step. To account for these divergent data, we propose a mechanism wherein the active nucleophilic fluorine species is a cobalt fluoride that forms a resting-state dimer. Axial ligation of the amine cocatalyst to (salen)Co facilitates dimer dissociation and is the origin of the observed cooperativity. On the basis of these studies, we show that significant improvements in the rates, turnover numbers, and substrate scope of the fluoride ring-opening reactions can be realized through the use of a linked salen framework. Application of this catalyst system to a rapid (5 min) fluorination to generate the unlabeled analog of a known PET tracer, F-MISO, is reported.
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Affiliation(s)
- Julia A Kalow
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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44
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Chen JL, Zheng F, Huang Y, Qing FL. Synthesis of γ-Monofluorinated Goniothalamin Analogues via Regio- and Stereoselective Ring-Opening Hydrofluorination of Epoxide. J Org Chem 2011; 76:6525-33. [DOI: 10.1021/jo200611w] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jun-Ling Chen
- College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China
| | - Feng Zheng
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
| | - Yangen Huang
- College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China
| | - Feng-Ling Qing
- College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
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45
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Piovesana S, Scarpino Schietroma DM, Bella M. Multiple Catalysis with Two Chiral Units: An Additional Dimension for Asymmetric Synthesis. Angew Chem Int Ed Engl 2011; 50:6216-32. [DOI: 10.1002/anie.201005955] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Indexed: 11/10/2022]
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46
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Piovesana S, Scarpino Schietroma DM, Bella M. Mehrfachkatalyse durch zwei chirale Einheiten: eine weitere Dimension in der asymmetrischen Synthese. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201005955] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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47
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Kalow JA, Doyle AG. Enantioselective Ring Opening of Epoxides by Fluoride Anion Promoted by a Cooperative Dual-Catalyst System. J Am Chem Soc 2010; 132:3268-9. [DOI: 10.1021/ja100161d] [Citation(s) in RCA: 222] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Julia A. Kalow
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544
| | - Abigail G. Doyle
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544
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48
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Yamakoshi H. Construction of Fluorinated Chiral Center. J SYN ORG CHEM JPN 2010. [DOI: 10.5059/yukigoseikyokaishi.68.962] [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]
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49
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Belokon Y, Chusov D, Peregudov A, Yashkina L, Timofeeva G, Maleev V, North M, Kagan H. Asymmetric meso-Epoxide Ring-Opening with Trimethylsilyl Cyanide Promoted by Chiral Binuclear Complexes of Titanium. Dichotomy of CC versus CN Bond Formation. Adv Synth Catal 2009. [DOI: 10.1002/adsc.200900523] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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50
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Asymmetric oxidative α-fluorination of 2-alkylphenylacetaldehydes with AgHF2 and ruthenium/PNNP catalysts. J Fluor Chem 2009. [DOI: 10.1016/j.jfluchem.2009.05.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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