- Nickel-Catalyzed Cross-Coupling of Ethyl Chlorofluoroacetate with Aryl Bromides
-
A combinatorial nickel-catalyzed monofluoroalkylation of aryl bromides with the industrial raw regent ethyl chlorofluoroacetate has been developed. The two key factors to successful conversion are the combination of nickel with readily available nitrogen and phosphine ligands and the using of a mixture of different solvents. Mechanistic investigations indicated a new zinc regent might generated in situ and be involved in the reaction process.
- Li, Han,Sheng, Jie,Wu, Bing-Bing,Li, Yan,Wang, Xi-Sheng
-
supporting information
p. 1741 - 1744
(2021/06/01)
-
- A Metallaphotoredox Strategy for the Cross-Electrophile Coupling of α-Chloro Carbonyls with Aryl Halides
-
Here, we demonstrate that a metallaphotoredox-catalyzed cross-electrophile coupling mechanism provides a unified method for the α-arylation of diverse activated alkyl chlorides, including α-chloroketones, α-chloroesters, α-chloroamides, α-chlorocarboxylic acids, and benzylic chlorides. This strategy, which is effective for a wide variety of aryl bromide coupling partners, is predicated upon a halogen atom abstraction/nickel radical-capture mechanism that is generically successful across an extensive range of carbonyl substrates. The construction and use of arylacetic acid products have further enabled two-step protocols for the delivery of valuable building blocks for medicinal chemistry, such as aryldifluoromethyl and diarylmethane motifs.
- Chen, Tiffany Q.,MacMillan, David W. C.
-
supporting information
p. 14584 - 14588
(2019/09/17)
-
- A Gas Chromatography-Mass Spectrometry Method for the Detection and Quantitation of Monofluoroacetate in Plants Toxic to Livestock
-
Monofluoroacetate (MFA) is a potent toxin that occurs in over 50 plant species in Africa, Australia, and South America and is responsible for significant livestock deaths in these regions. A gas chromatography-mass spectrometry (GC-MS) method for the analysis of MFA in plants based on the derivatization of MFA with n-propanol in the presence of sulfuric acid to form propyl fluoroacetate was developed. This method compared favorably to a currently employed high-performance liquid chromatography-mass spectrometry (HPLC-MS) method for the analysis of MFA in plants. The GC-MS method was applied to the analysis of MFA in herbarium specimens of Fridericia elegans, Niedenzuella stannea, N. multiglandulosa, N. acutifolia, and Aenigmatanthera lasiandra. This is the first report of MFA being detected in F. elegans, N. multiglandulosa, N. acutifolia, and A. lasiandra, some of which have been reported to cause sudden death or that are toxic to livestock.
- Santos-Barbosa, Joyce M.,Lee, Stephen T.,Cook, Daniel,Gardner, Dale R.,Viana, Luis Henrique,Ré, Nilva
-
p. 1428 - 1433
(2017/03/01)
-
- Method for synthesizing fluoro ethyl acetate and fluoro methyl acetate
-
The invention provides a method for synthesizing fluoro ethyl acetate or fluoro methyl acetate. According to the method, chloro-alkyl imidazole ionic liquid and/or bromo-alkyl imidazole ionic liquid is taken as the catalyst, ethyl chloroacetate or ethyl chloroacetate and alkali metal fluorides are taken as raw materials, a polar aprotic solvent is taken as the reaction medium, filtration is conducted after reaction is conducted for a while at a set temperature to remove inorganic salt, and then fluoro ethyl acetate or fluoro methyl acetate is obtained.
- -
-
Paragraph 0025; 0026; 0027
(2016/10/07)
-
- Activation reactions of 1,1-dialkoxoalkanes and unsaturated O-donors by titanium tetrafluoride
-
The reactivity of TiF4 with a variety of non cyclic 1,1-dialkoxoalkanes [CH2(OR)2, R = Me, Et, Me 2C(OMe)2, MeCH(OEt)2, ClCH2CH(OEt) 2, CH(OMe)3, PhCCCH(OEt)2], 1,3-dioxolane, N2CHCO2Et and 1,2-epoxybutane has been investigated. Activation, including fragmentation and/or rearrangement of the organic moiety, has been observed at room temperature in some cases; it generally occurs unselectively via C-O bond fission and the formation of new C-O, C-H and C-C bonds. Small differences in the structure of the organic substrate may determine significant differences in the reactivity with TiF4.
- Marchetti, Fabio,Pampaloni, Guido,Biancalana, Lorenzo
-
experimental part
p. 135 - 139
(2012/05/20)
-
- PRODUCTION OF COMPOUNDS COMPRISING CF30 GROUPS
-
The present invention relates to a process for the preparation of compounds containing CF3O groups using compounds containing at least one group Y, in which Y=—Hal, —OSO2(CF2)zF, —OSO2CzH2z+1 (z=1-10), —OSO2F, —OSO2Cl, —OC(O)CF3— or —OSO2Ar, to a process for the preparation of compounds containing CF3O groups using KOCF3 and/or RbOCF3, and to novel compounds containing CF3O groups, and to the use thereof.
- -
-
Page/Page column 10-11
(2011/04/24)
-
- Palladium-catalyzed cross-coupling of ethyl α-bromo-α- fluoroacetate with arylboronic acids: Facile synthesis of α-aryl-α- fluoroacetate
-
Palladium-catalyzed Suzuki-Miyaura coupling reactions of ethyl α-bromo-α-fluoroacetate with various structurally diverse arylboronic acids using a phosphine ligand proceeded smoothly to afford α-aryl-α-fluoroacetate in moderate to good yields. This method provides a practical and efficient route to diverse α-monofluorinated α-arylcarbonyl compounds. Georg Thieme Verlag Stuttgart New York.
- Guo, Chen,Yue, Xuyi,Qing, Feng-Ling
-
experimental part
p. 1837 - 1844
(2010/08/19)
-
- Cocatalysis in phase-transfer catalyzed fluorination of alkyl halides and sulfonates
-
Phase-transfer catalyzed (PTC) fluorination of alkyl halides and sulfonates with solid KF proceeds efficiently when cocatalyst triphenyltin fluoride is used. The cocatalytic action of the tin compound consists in continuous formation of difluorotriphenylstannate anion that as the tetraalkyloammonium salt enter the solution where it reacts with alkyl halides to produce alkyl fluorides. The cocatalytic system was used to synthesis of 1,1-difluoroalkanes in two steps from aldehydes. A new kind of PTC was elaborated in which Ph 3SnF acts as phase transfer catalyst via continuous formation of potassium salts of diflurotriphenylstannate anions soluble in dipolar aprotic solvents. A new, simple and general method of synthesis of tetraalkylammonium and potassium salts of difluorotriorgano-tin, silicon and germanium anions is reported.
- Ma?kosza,Bujok
-
p. 209 - 216
(2007/10/03)
-
- Pyrimidine compounds
-
5-Bromo-2-iodopyrimidine is used to synthesize a range of chemical compounds including liquid crystalline compounds.
- -
-
-
- Alkylation and decarboxylation of ethyl 2-fluoro-3-oxobutanoate as a route to functionalised α-fluoro-ketones
-
Alkylation and decarboxylation of α-fluoro-β-ketoesters such as ethyl 2-fluoro-3-oxobutanoate offers a versatile route to a range of fluoro-ketoalkenes, demonstrating the synthetic utility of using α-fluoro-β-ketoesters as synthons for the preparation of synthetically more sophisticated selectively fluorinated systems.
- Hutchinson,Sandford, Graham,Vaughan, Julian F.S.
-
p. 2867 - 2876
(2007/10/03)
-
- Novel and practical preparation of α-fluoro-functionalized esters from fluoroiodoacetates
-
The addition reaction of fluoroiodoacetates 2 to various electron-rich alkenes 3 initiated by iron powder in dry THF at 70-80°C gave 1:1 adducts 4 in good yields. A variety of functionalities in the alkenes such as trimethylsilyl, alkoxy, acetoxy, hydroxy and ester could be tolerated under the reaction conditions. Reduction of the adducts 4 with Zn-AcOH in ethanol or Zn-NiCl2·OH2O in moist THF was readily accomplished, and the overall procedure was amenable to a convenient one-flask procedure. Treatment of fluoroiodoacetates 2 with electron-deficient alkenes 7 in the presence of an Fe-CrCl3·OH2O-bpy bimetal redox system in ethanol at 70-80°C resulted in the formation of iodine-free 1:1 adducts 8 in moderate to good yields. It is proposed that the addition reactions of fluoroiodoacetates 2 to electronrich and electron-deficient alkenes proceeded through a single-electron-transfer mechanism.
- Zhi, Chengxin,Chen, Qing-Yun
-
p. 1741 - 1747
(2007/10/03)
-
- Preparation of α-fluoro-β-per(poly) fluoroalkyl-substituted enol ethers
-
Fluorocarboethoxymethylene tri-n-butylphosphorane, Bu3P=CFCOOEt (3), reacts with per- and poly-fluoroalkyl-substituted carboxylic acid esters, ethyl formate and γ-butyrolactone to give the corresponding enol ethers, RFC (OEt)=CFCOOEt (4), in good yield. Non-activated esters failed to react with 3. With the anion derived from ethyl diethylphosphonofluoroacetate, (EtO)2P(O)CFHCOOEt (5), a mixture of 4 and β-ketoesters, RFC(O)CFHCOOEt (7), is formed.
- Thenappan, Alagappan,Burton, Donald J.
-
-
- A facile synthesis of organofluorine compounds using a semi-molten mixture of tetrabutylammonium bromide and an alkali metal fluoride
-
A semi-molten mixture of tetrabutylammonium bromide and an alkali metal fluoride (KF or CsF) has been found to be an efficient reagent system for the preparation of organofluorine compounds, e.g., CH3(CH2)7F, CH2=CH-CH2F, FCH2CO2C2H5, C6H5COF, and related compounds through facile fluoride-ion exchange with organohalides.The system provides a simple and convenient alternative to 'anhydrous' tetrabutylammonium fluoride for the synthesis of organofluorine compounds. - Keywords: Semi-molten mixture; Tetrabutylammonium bromide; Alkali metal fluorides; Organofluorine compounds; NMR spectroscopy
- Bhadury, Pinaki S.,Pandey, Mamta,Jaiswal, Devendra K.
-
p. 185 - 188
(2007/10/02)
-
- Nickel Catalyzed Reaction of Iodofluoroacetates with Alkenes as a Facile Route to α-Fluoroesters
-
Reaction of iodofluoroacetates with alkenes and zinc in the presence of nickel dichloride hexahydrate and pyridine in THF affords the corresponding α-fluoroesters in good yields.
- Wang, Yong,Yang, Zhen-Yu,Burton, Donald J.
-
p. 2137 - 2140
(2007/10/02)
-
- Analyse structurale des derives fonctionnels des acides carboxyliques Partie III. Acetate d'ethyle et derives α-halogenes
-
Methylene bending mode analysis of ethyl esters of acetic and haloacetic acids XCH2CO2C2H5 where X=H(I), F(II), Cl(III), Br(IV) and I(V) reveals that in the dissolved state (CCl4) these compounds have conformations induced by rotating motion of the XCH2 and C2H5 groups ( (II), (III) and (IV) ) or by C2H5 group rotation exclusively ( (I) and (V) ).In the last case, (I) exists in gauche and anti conformations while (V) occurs in gauche-gauche and gauche-anti conformations.A theoretical study of compounds (I), (II) and (III) by the PCILO method and Onsager formalism leads to the following conclusions.The conformers of (I) have a dihedral angle (H3)C-C(H2)-O-C of 70 deg (gauche conformer) and 180 deg (anti conformer).For (II) and (III), there are four stable conformers whose dihedral angles φ3=(H3)C-C(H2)-O-C and θ=X-C-C=O values are in agreement with C2H5 and CH2X group orientations found in experimental analysis.
- Maury, Catherine,Petrissans, Jean
-
p. 221 - 232
(2007/10/02)
-
- DEFLUORATION PHOTOREDUCTIVE D'ESTERS D'ACIDES PERFLUORES: SYNTHESE D'HYDRO-2 PERFLUOROALCANOATES D'ALKYLE
-
Photoreduction in hexamethylphosphortriamide was found to be an efficient method to selectively reduce C-F bonds α to the carboxyl group of alkyl perfluoroesters.The reation proceeds by photoinduced electronic transfer from the excited phosphoramide.Conditions were found to remove selectively one fluorine and the reaction was applied to the synthesis of alkyl 2-hydro perfluoroesters.
- Portella, C.,Iznaden, M.
-
p. 6467 - 6478
(2007/10/02)
-
- EASY AND EFFICIENT HETEROGENEOUS NUCLEOPHILIC FLUORINATION WITHOUT SOLVENT
-
In the absence of solvent, either or were found to be effective and practical reagents for the fluorination of several organic halides under mild conditions.
- Bram, Georges,Loupy, Andre,Pigeon, Philippe
-
p. 1661 - 1668
(2007/10/02)
-
- The Combination of Potassium Fluoride and Calcium Fluoride: A Useful Heterogeneous Fluorinating Reagent
-
The combination of potassium fluoride and calcium fluoride was found to be an effective and practical solid reagent for the fluorination of various organic chlorides and bromides under mild conditions.
- Ichihara, Junko,Matsuo, Toshiya,Hanafusa, Terukiyo,Ando, Takashi
-
p. 793 - 794
(2007/10/02)
-
- Fluorinated carbamate insecticides
-
Fluorinated carbamoyl sulfides, such as N,N'[thiobis[(methylimino)carbonyloxy]]bis[2,2,2-trifluoroethanimidothioic acid], dimethyl ester, useful for control of insects.
- -
-
-
- ENHANCED EFFECT OF SPRAY-DRIED POTASSIUM FLUORIDE ON FLUORINATION
-
Spray-dried potassium fluoride was found to be much less hygroscopic and much more effective as a fluorinating agent than usual calcine-dried potassium fluoride.Organic compounds containing an activated halogen atom were readily fluorinated in acetonitrile with spray-dried potassium fluoride.
- Ishikawa, Nobuo,Kitazume, Tomoya,Yamazaki, Takashi,Mochida, Yoshiharu,Tatsuno, Toshio
-
p. 761 - 764
(2007/10/02)
-
- ACTION DU METHYLTRI(N-BUTYL)FLUOROPHOSPHORANE SUR LES HALOGENURES ET LES SULFONATES D'ALKYLE
-
Monofluorophosphoranes R3MePF are used in exchange reactions to prepare monofluorinated organic compounds.Tri(n-butyl)methylfluorophosphorane (n-Bu3MePF), easily available, is the most reactive.In solvents of low polarity or even in non-polar solvents, it reacts at -70 deg C with alkyl sulphonates and halides activated by ester, ketone, or ether functions.Thus, fluorinated epoxides can be obtained directly by exchange from their chlorinated or brominated homologues.
- Leroy, J.,Bensoam, J.,Humiliere, M.,Wakselman, C.,Mathey, F.
-
p. 1931 - 1936
(2007/10/02)
-