- Method for co-producing 2-fluoropropionate and ethyl difluoroacetate
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The invention discloses a method for co-producing 2-fluoropropionate and ethyl difluoroacetate. The method comprises: (a) carrying out a reaction on a fluorinating reagent and a lactate for 0.5-7 h ata reaction temperature of 30-120 DEG C according to a molar ratio of 0.5-2:1, cooling the reaction material after completing the reaction, adding a nitrogen-containing compound, and carrying out pressure reducing rectification to obtain a 2-fluoropropionate product and N,N-dimethyl difluoroacetamide; and (b) adding concentrated sulfuric acid to a mixture of anhydrous ethanol and the N,N-dimethyldifluoroacetamide obtained in the step (a), carrying out a reaction for 1-10 h at a reaction temperature of 50-170 DEG C, cooling after completing the reaction, separating the liquid, and carrying outrectification to obtain the ethyl difluoroacetate product, wherein a molar ratio of anhydrous ethanol to N,N-dimethyl difluoroacetamide is 0.5-4.5:1, and a molar ratio of concentrated sulfuric acid to N,N-dimethyl difluoroacetamide is 0.1-1.5:1. According to the present invention, the method has advantages of environmental protection, high yield and low cost.
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Paragraph 0035; 0036
(2019/05/04)
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- A 2 - fluorination ester synthesis method
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The invention discloses a 2-fluoropropionate synthetizing method. The method comprise the steps of 1, adding ester to a four-mouth flask provided with a condenser pipe, wherein the general formula of the ester is CH3CHXCOOR, and R represents alkyl; 2, adding an addition agent, a catalyst and solvent to the four-mouth flask, and then adding a fluorinated reagent and conducting stirring to obtain reaction liquid; 3, heating the reaction liquid to a set temperature, wherein reaction time is 3-16 h; 4, conducting rectification after reaction ends to obtain a 2-fluoropropionate target product. According to the method, cheap 2-CH3CHClCOOR is used as the raw material, and fluorination is conducted with potassium fluoride in the presence of the addition agent to obtain the 2-fluoropropionate. The method has the advantages that the reaction condition is mild, the yield is high, and cost is low. Due to the fact that the addition agent is added, generation of high-boiling by-products can be restrained, and then reaction selectivity is improved.
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Paragraph 0026; 0027
(2018/02/04)
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- Method for preparing a fluorinated organic compound
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A method for preparing a fluorinated organic compound (II) from an organic compound (I) comprising at least one nucleofugal group Nu, and also a preparation of different specific organic compounds, in particular a fluoro-methylpyrazole compound. The method comprises: a reaction, in the presence of water, of the organic compound (I) and at least one salt providing at least one fluoride anion; and a replacement of at least one nucleofugal group Nu of the compound (I) with a fluorine atom, in order to obtain the fluorinated organic compound (II).
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Paragraph 0293-0294
(2014/06/11)
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- Process for Preparing Fluorinated Molecules
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The present invention relates to a process for preparing α-fluorinated esters from α-hydroxy esters by reaction with a dihalocarbonyl compound (or an equivalent) to give haloformates and further to give fluoroformates, which are then decomposed thermally in the presence of suitable catalysts. The invention further relates to the individual steps of the process and in some cases to novel fluoroformates.
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Page/Page column 8
(2008/06/13)
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- Conformational analysis. Part 33. An NMR, solvation and theoretical investigation of conformational isomerism in N,N-dimethylfluoroacetamide and N,N-dimethyl-α-fluoropropionamide
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The solvent and temperature dependence of the 1H and 13C NMR spectra of N,N-dimethylfluoroacetamide (DMFA) and N,N-dimethyl-α-fluoropropionamide (DMFP) are reported and the 5JCF, 1JCF and 4JCF couplings analysed by solvation theory. Density function theory (DFT) at the B3LYP/6-311 +G(d,p) level with ZPE (zero point energy) corrections was used to obtain the conformer geometries. In DMFA, the DFT method gave only two minima for the cis (F-C-C=O, 0°) and gauche (F-C-C=O, 140.6°) rotamers. The trans rotamer was not a minimum in the energy surface. Assuming only the cis and gauche forms, the observed couplings when analysed by solvation theory gave the energy difference (Ecis - Eg) of 2.5 kcal mol-1 in the vapour phase, (cf. the ab initio value of 2.3 kcal mol-1) decreasing to 0.87 kcal mol-1 in CCl4 and to -1.29 kcal mol-1 in DMSO. In DMFP the ab initio calculations gave three minima; the cis (F-C-C=O, 30.4°), gauche-1 (F-C-C=O, 144.7°) and gauche-2 (F-C-C=O, -124.1°) rotamers with (Ecis - Eg2) equal to 2.5 kcal mol-1 and (Eg1 - Eg2) equal to 0.3 kcal mol-1. The observed couplings were analysed by solvation theory assuming one "average" gauche conformer to give (Ecis - Eg(AV)) equal to 2.1 kcal mol-1 in the vapour phase, decreasing to 0.83 kcal mol-1 in CCl4 and to -1.11 kcal mol-1 in DMSO.
- Tormena, Claudio F.,Rittner, Roberto,Abraham, Raymond J.,Basso, Ernani A.,Pontes, Rodrigo M.
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p. 2054 - 2059
(2007/10/03)
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- A semi-molten mixture of hexadecyltributylphosphonium bromide and potassium fluoride in the synthesis of organofluorine compounds
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A facile and effective reagent system comprising of a semi-molten mixture of hexadecyltributylphosphonium bromide and potassium fluoride has been developed and its scope has been investigated in nucleophilic fluoride exchange with various organohalides. This simple and convenient reagent system provides organofluorine compounds in high yields even with haloesters in which fluoride catalysed elimination is also feasible.
- Bhadury, Pinaki S.,Raza, Syed K.,Jaiswal, Devendra K.
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p. 115 - 117
(2007/10/03)
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- Stereoselective synthesis of 3-fluoro azetidinones via the condensation of 2-fluoropropanethioate lithium enolate with imines
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S-Phenyl-2-fluoropropanethioate (1) was treated with lithium diisopropylamide in THF at -78°C to give rise to the lithium enolate, which underwent stereoselective condensation with a variety of aldehyde imines (2) at room temperature to afford the corresp
- Ishihara,Ichihara,Yamanaka
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p. 255 - 262
(2007/10/02)
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- REACTIONS OF HALOGEN FLUORIDES. XIII. NEW POSSIBILITIES FOR OXIDATIVE NUCLEOPHILIC FLUORINATION OF BROMINE-SUBSTITUTED ESTERS BY THE HEXACHLOROMELAMINE-HYDROGEN FLUORIDE SYSTEM
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Primary, secondary, and tertiary bromine atoms in bromine-substituted esters, including the bromine atoms of the CBr2 group at the α position to the ester group, are substituted effectively by a bromine atom in the hexachloromelamine-liquid hydrogen fluoride system under normal conditions.New methods were developed for the production of alkyl and fluoroalkyl 2,3-dihalogeno-2-fluoropropionates, which are key compounds in the synthesis of α-fluoroacrylates.
- Chuvatkin, N. N.,Panteleeva, I. Yu.,Kurskii, Yu. A.,Boguslavskaya, L. S.
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p. 1450 - 1456
(2007/10/02)
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- Simple synthesis of optically active 2-fluoropropanoic acid and analogs of high enantiomeric purity
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A very simple synthesis of optically active 2-fluoropropanoic acid 1 (R=CH3, R′=H) and analogs of high enantiomeric purity was developed using the sulfonates 2 of the corresponding optically active 2-hydroxycarboxylic esters and potassium fluor
- Fritz-Langhals, Elke,Schuetz, Gabi
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p. 293 - 296
(2007/10/02)
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- REACTION OF HYDROXY AND CARBONYL COMPOUNDS WITH SULFUR TETRAFLUORIDE. XII. REACTIONS OF ESTERS OF ALIPHATIC α- AND β-HYDROXY CARBOXYLIC ACIDS WITH SULFUR TETRAFLUORIDE
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The esters of aliphatic and α- and β-hydroxy carboxylic acids react with sulfur tetrafluoride to form the corresponding esters of fluoro carboxylic acids and alkoxycarbonylalkyl fluorosulfites.If electron-withdrawing substituents are introduced at the α position to the carbon atom attached to the hydroxyl group, the reactions of the esters of hydroxy acids with sulfur tetrafluoride take place with substitution of the carbonyl oxygen by two fluorine atoms.
- Motnyak, L. A.,Burmakov, A. I.,Kunshenko, B. V.,Neizvestnaya, T. A.,Alekseeva, L. A.,Yagupol'skii, L. M.
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p. 1063 - 1074
(2007/10/02)
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