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Dominique Cahard - One of the best experts on this subject based on the ideXlab platform.
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Electrophilic Fluorination with n f reagents
Organic Reactions, 2008Co-Authors: Jerome Baudoux, Dominique CahardAbstract:The synthesis of selectively fluorinated molecules is an important challenge in organic chemistry. This topic has received considerable attention because of the utility of fluorinated compounds in a wide variety of disciplines. There are three types of Fluorination depending on whether the fluorine atom is radical, anionic, or cationic. Fluorine radicals are of little synthetic use because of the difficulties in controlling their reactivity. Fluorine is utilized in nucleophilic as well as Electrophilic Fluorinations Molecular fluorine is the simplest reagent of this type, however, its safe handling is difficult. Stable, selective reagents are crucial to the development of Electrophilic Fluorination. N-F reagents have emerged as generally safer and easier to handle selective sources of Electrophilic fluorine. N-F reagents offer a range of fluorinating powers and some are available commercially. Two classes are known: neutral N-F reagents and quaternary ammonium N-F reagents (quaternary salts are usually the more powerful). N-F reagents popularity arises because they posses a long shelf life, several are commercially available, and they can be handled safely in glassware. The drawback is the preferential use of molecular fluorine for their preparation. This article deals with the preparation and the use of all types of Electrophilic fluorinating agents possessing the N-F moiety. Keywords: Electrophilic Fluorination, N-F reagents; N-Fluorosulfonamides; N-Fluorosulfonimides; N-Fluorocarboxamides; N-Fluoro heterocycles; N-Fluoroammonium compounds; N-Fluoroiminium compounds; Alkanes; Heterocycles; Glycals; Metal enolates; Carbonyls; Direct Fluorination; Organophosphorus compounds; Organosulfur compounds; Fluorodemetalation; Diastereoselectivity; Enantioselectivity; Method comparisons; Experimental procedures
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Organic Reactions - Electrophilic Fluorination with N–F Reagents
Organic Reactions, 2008Co-Authors: Jerome Baudoux, Dominique CahardAbstract:The synthesis of selectively fluorinated molecules is an important challenge in organic chemistry. This topic has received considerable attention because of the utility of fluorinated compounds in a wide variety of disciplines. There are three types of Fluorination depending on whether the fluorine atom is radical, anionic, or cationic. Fluorine radicals are of little synthetic use because of the difficulties in controlling their reactivity. Fluorine is utilized in nucleophilic as well as Electrophilic Fluorinations Molecular fluorine is the simplest reagent of this type, however, its safe handling is difficult. Stable, selective reagents are crucial to the development of Electrophilic Fluorination. N-F reagents have emerged as generally safer and easier to handle selective sources of Electrophilic fluorine. N-F reagents offer a range of fluorinating powers and some are available commercially. Two classes are known: neutral N-F reagents and quaternary ammonium N-F reagents (quaternary salts are usually the more powerful). N-F reagents popularity arises because they posses a long shelf life, several are commercially available, and they can be handled safely in glassware. The drawback is the preferential use of molecular fluorine for their preparation. This article deals with the preparation and the use of all types of Electrophilic fluorinating agents possessing the N-F moiety. Keywords: Electrophilic Fluorination, N-F reagents; N-Fluorosulfonamides; N-Fluorosulfonimides; N-Fluorocarboxamides; N-Fluoro heterocycles; N-Fluoroammonium compounds; N-Fluoroiminium compounds; Alkanes; Heterocycles; Glycals; Metal enolates; Carbonyls; Direct Fluorination; Organophosphorus compounds; Organosulfur compounds; Fluorodemetalation; Diastereoselectivity; Enantioselectivity; Method comparisons; Experimental procedures
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enantioselective and diastereoselective synthesis of fluorinated dipeptides by late Electrophilic Fluorination
Tetrahedron Letters, 2005Co-Authors: Barbara Mohar, Damjan Sterk, Laurent Ferron, Dominique CahardAbstract:A series of optically enriched monofluorinated dipeptides incorporating an α-fluoro-α-amino acid were prepared by enantio- and diastereoselective Electrophilic Fluorination. This previously unsuccessful approach to fluorinated dipeptides can now be achieved with up to 73:27 enantiomeric ratio and high >98:2 diastereomeric ratio.
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screening of chiral catalysts for enantioselective Electrophilic Fluorination of β ketoesters
Journal of Fluorine Chemistry, 2004Co-Authors: Dominique CahardAbstract:Abstract A variety of oxygen- and nitrogen-containing chiral ligands in combination with various metals have been screened in the enantioselective Electrophilic Fluorination of β-ketoesters. This study involved the use of readily available substrates, chiral ligands and Electrophilic fluorinating agents. In particular, heterobimetallic Al–Li–BINOL complex allowed to obtain enantiomerically enriched α-fluoro-β-ketoesters in high yields and moderate enantioselectivities; up to 67% ee. A comparison with previously reported chiral ligands is provided.
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copper ii triflate bis oxazoline catalysed enantioselective Electrophilic Fluorination of β ketoesters
Tetrahedron-asymmetry, 2004Co-Authors: Dominique CahardAbstract:Abstract A new efficient catalytic enantioselective Electrophilic Fluorination of cyclic and acyclic β-ketoesters is developed. As low as 1 mol % of chiral bis(oxazoline)-copper triflate complexes catalyses the Fluorination by means of N -fluorobenzenesulfonimide. The use of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) is crucial for achieving high enantioselectivity.
Kun Zhang - One of the best experts on this subject based on the ideXlab platform.
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Electrophilic Fluorination of secondary phosphine oxides and its application to p o bond construction
Journal of Organic Chemistry, 2016Co-Authors: Qian Chen, Jiekun Zeng, Yulin Huang, Kun ZhangAbstract:A novel and efficient Electrophilic Fluorination of secondary phosphine oxides with Selectfluor has been achieved. This transformation provides direct access to phosphoric fluorides in up to 92% yield under mild conditions. In addition, P–O bond construction via a one-pot coupling process of secondary phosphine oxides with water or alcohols in the presence of Selectfluor leads to the formation of phosphinic acids or phosphinates in up to 96% yield.
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Electrophilic Fluorination of Secondary Phosphine Oxides and Its Application to P–O Bond Construction
Journal of Organic Chemistry, 2016Co-Authors: Qian Chen, Jiekun Zeng, Yulin Huang, Kun ZhangAbstract:A novel and efficient Electrophilic Fluorination of secondary phosphine oxides with Selectfluor has been achieved. This transformation provides direct access to phosphoric fluorides in up to 92% yield under mild conditions. In addition, P–O bond construction via a one-pot coupling process of secondary phosphine oxides with water or alcohols in the presence of Selectfluor leads to the formation of phosphinic acids or phosphinates in up to 96% yield.
Veronique Gouverneur - One of the best experts on this subject based on the ideXlab platform.
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Flipping fluoride's reactivity
Nature Chemistry, 2012Co-Authors: Veronique GouverneurAbstract:A sophisticated palladium( IV )-based species allows nucleophilic fluoride to react as an Electrophilic Fluorination reagent. This long-awaited reactivity will be especially useful in the preparation of radiochemically labelled molecules for positron emission tomography studies.
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Radiochemistry: Flipping fluoride's reactivity.
Nature Chemistry, 2012Co-Authors: Veronique GouverneurAbstract:A sophisticated palladium(IV)-based species allows nucleophilic fluoride to react as an Electrophilic Fluorination reagent. This long-awaited reactivity will be especially useful in the preparation of radiochemically labelled molecules for positron emission tomography studies.
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Highly Diastereoselective Electrophilic Fluorination of Cyclic syn-β-Hydroxysilanes
Synlett, 2007Co-Authors: Sophie Purser, Chris Wilson, Peter R. Moore, Veronique GouverneurAbstract:A synthesis of enantioenriched fluorinated carbocycles has been developed combining a sequential enantioselective silyl-allylboration-ring-closing metathesis with a highly diastereoselective Electrophilic Fluorination.
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Electrophilic Fluorination of organosilanes
Organic and Biomolecular Chemistry, 2006Co-Authors: Matthew Tredwell, Veronique GouverneurAbstract:The Fluorination of organosilanes with the silyl groups directly attached or adjacent to an aryl or alkenyl group has been only very recently examined despite the fact that the corresponding fluorinated products are synthetically useful building blocks. In these reactions, the silyl group enhances the reactivity of the π-nucleophile and controls the sense of regiochemistry upon addition of the Electrophilic source of fluorine. These reactions take advantage of the β effect of the silicon–carbon bond and recent results from the literature revealed that this chemistry allows for the preparation of a variety of novel fluorinated building blocks including enantioenriched derivatives.
Jerome Baudoux - One of the best experts on this subject based on the ideXlab platform.
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Electrophilic Fluorination with n f reagents
Organic Reactions, 2008Co-Authors: Jerome Baudoux, Dominique CahardAbstract:The synthesis of selectively fluorinated molecules is an important challenge in organic chemistry. This topic has received considerable attention because of the utility of fluorinated compounds in a wide variety of disciplines. There are three types of Fluorination depending on whether the fluorine atom is radical, anionic, or cationic. Fluorine radicals are of little synthetic use because of the difficulties in controlling their reactivity. Fluorine is utilized in nucleophilic as well as Electrophilic Fluorinations Molecular fluorine is the simplest reagent of this type, however, its safe handling is difficult. Stable, selective reagents are crucial to the development of Electrophilic Fluorination. N-F reagents have emerged as generally safer and easier to handle selective sources of Electrophilic fluorine. N-F reagents offer a range of fluorinating powers and some are available commercially. Two classes are known: neutral N-F reagents and quaternary ammonium N-F reagents (quaternary salts are usually the more powerful). N-F reagents popularity arises because they posses a long shelf life, several are commercially available, and they can be handled safely in glassware. The drawback is the preferential use of molecular fluorine for their preparation. This article deals with the preparation and the use of all types of Electrophilic fluorinating agents possessing the N-F moiety. Keywords: Electrophilic Fluorination, N-F reagents; N-Fluorosulfonamides; N-Fluorosulfonimides; N-Fluorocarboxamides; N-Fluoro heterocycles; N-Fluoroammonium compounds; N-Fluoroiminium compounds; Alkanes; Heterocycles; Glycals; Metal enolates; Carbonyls; Direct Fluorination; Organophosphorus compounds; Organosulfur compounds; Fluorodemetalation; Diastereoselectivity; Enantioselectivity; Method comparisons; Experimental procedures
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Organic Reactions - Electrophilic Fluorination with N–F Reagents
Organic Reactions, 2008Co-Authors: Jerome Baudoux, Dominique CahardAbstract:The synthesis of selectively fluorinated molecules is an important challenge in organic chemistry. This topic has received considerable attention because of the utility of fluorinated compounds in a wide variety of disciplines. There are three types of Fluorination depending on whether the fluorine atom is radical, anionic, or cationic. Fluorine radicals are of little synthetic use because of the difficulties in controlling their reactivity. Fluorine is utilized in nucleophilic as well as Electrophilic Fluorinations Molecular fluorine is the simplest reagent of this type, however, its safe handling is difficult. Stable, selective reagents are crucial to the development of Electrophilic Fluorination. N-F reagents have emerged as generally safer and easier to handle selective sources of Electrophilic fluorine. N-F reagents offer a range of fluorinating powers and some are available commercially. Two classes are known: neutral N-F reagents and quaternary ammonium N-F reagents (quaternary salts are usually the more powerful). N-F reagents popularity arises because they posses a long shelf life, several are commercially available, and they can be handled safely in glassware. The drawback is the preferential use of molecular fluorine for their preparation. This article deals with the preparation and the use of all types of Electrophilic fluorinating agents possessing the N-F moiety. Keywords: Electrophilic Fluorination, N-F reagents; N-Fluorosulfonamides; N-Fluorosulfonimides; N-Fluorocarboxamides; N-Fluoro heterocycles; N-Fluoroammonium compounds; N-Fluoroiminium compounds; Alkanes; Heterocycles; Glycals; Metal enolates; Carbonyls; Direct Fluorination; Organophosphorus compounds; Organosulfur compounds; Fluorodemetalation; Diastereoselectivity; Enantioselectivity; Method comparisons; Experimental procedures
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ionic liquids as solvents of choice for Electrophilic Fluorination Fluorination of indoles by f teda bf4
Tetrahedron Letters, 2002Co-Authors: Jerome Baudoux, Dominique Cahard, Annefrederique Salit, Jeanchristophe PlaqueventAbstract:Abstract Selectfluor™ was shown to be soluble in ionic liquid, thus allowing the ‘green’ Electrophilic Fluorination of indole compounds in high chemoselectivity and yields.
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Electrophilic Fluorination mediated by cinchona alkaloids highly enantioselective synthesis of α fluoro α phenylglycine derivatives
Angewandte Chemie, 2001Co-Authors: Barbara Mohar, Jeanchristophe Plaquevent, Jerome Baudoux, Dominique CahardAbstract:: A decisive step forward: A one-step Fluorination on modified cinchona alkaloids produced a new range of enantiopure fluorinating agents that display high enantioselectivities in Electrophilic Fluorination. The first enantioselective synthesis of N-protected α-fluorophenylglycine derivatives was achieved with an enantiomeric excess up to 94 % [Eq. (a); R=Et, CN; HMDS=hexamethyldisilazanide].
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Electrophilic Fluorination Mediated by Cinchona Alkaloids: Highly Enantioselective Synthesis of α‐Fluoro‐α‐phenylglycine Derivatives
Angewandte Chemie, 2001Co-Authors: Barbara Mohar, Jeanchristophe Plaquevent, Jerome Baudoux, Dominique CahardAbstract:: A decisive step forward: A one-step Fluorination on modified cinchona alkaloids produced a new range of enantiopure fluorinating agents that display high enantioselectivities in Electrophilic Fluorination. The first enantioselective synthesis of N-protected α-fluorophenylglycine derivatives was achieved with an enantiomeric excess up to 94 % [Eq. (a); R=Et, CN; HMDS=hexamethyldisilazanide].
Gang Zhao - One of the best experts on this subject based on the ideXlab platform.
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construction of fluorinated pyrazole derivatives via a one pot tandem c h insertion Electrophilic Fluorination reaction
Tetrahedron, 2014Co-Authors: Kai Zhang, Gang ZhaoAbstract:A series of 4-fluoro-pyrazole derivatives were synthesized in moderate to good yields via a one-pot tandem procedure involving an Rh-2(OAc)(4)-catalyzed C-H insertion and an Electrophilic Fluorination with N-fluorobenzenesulfonimide (NFSI). (C) 2014 Elsevier Ltd. All rights reserved.
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Construction of fluorinated pyrazole derivatives via a one-pot tandem C-H insertion/Electrophilic Fluorination reaction
Tetrahedron, 2014Co-Authors: Kai Zhang, Gang ZhaoAbstract:A series of 4-fluoro-pyrazole derivatives were synthesized in moderate to good yields via a one-pot tandem procedure involving an Rh-2(OAc)(4)-catalyzed C-H insertion and an Electrophilic Fluorination with N-fluorobenzenesulfonimide (NFSI). (C) 2014 Elsevier Ltd. All rights reserved.
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direct double Electrophilic Fluorination of allenoic acids and tosylamides to give 1 1 difluoroallylic heterocyclic compounds
Chinese Journal of Chemistry, 2011Co-Authors: Zhuo Chai, Yingpeng Lu, Peng Li, Gang ZhaoAbstract:A novel and facile preparation of 1,1-difluoroallyl substituted five-membered lactones or pyrrolidines in moderate yields through direct double Electrophilic Fluorination of 4,5-allenoic acids or tosylamides with SelectfluorTM F-TEAD-BF4 is described.
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facile synthesis of monofluoro γ lactones and pyrrolidine derivatives via Electrophilic Fluorination of allenoic acids and amides
Chinese Journal of Chemistry, 2009Co-Authors: Zhuo Chai, Gang ZhaoAbstract:A convenient method to synthesize a series of monofluoro γ-lactones and pyrrolidine derivatives in moderate to good yields via the Electrophilic Fluorination of γ-allenoic acids and tosylamides using Selectfluor was developed.