769-39-1Relevant articles and documents
Method for synthesizing 2,3,5,6-tetrafluorophenol
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Paragraph 0023-0032, (2021/08/07)
The invention discloses a method for synthesizing 2,3,5,6-tetrafluorophenol, belonging to the field of fine chemical engineering. According to the invention, short-chain sodium aliphatate with large steric hindrance and pentafluorobenzoic acid are subjected to a reflux reaction in a polar solvent; after the reaction is finished, strong acid hydrolysis decarboxylation and steam distillation are performed; and a water vapor distillation product is rectified to obtain 2,3,5,6-tetrafluorophenol, the purity of 2,3,5,6-tetrafluorophenol is 99.8% or above, and the yield of 2,3,5,6-tetrafluorophenol is 88% or above. The method has the remarkable characteristics of simplicity and convenience in operation and small environmental pollution, and has a relatively good economic value in preparation of a 2,3,5,6-tetrafluorophenol product.
Synthesis method of fluorine-containing phenol structure compound
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Paragraph 0037-0038, (2021/03/13)
The invention discloses a synthesis method of a fluorine-containing phenol structure compound, and belongs to the technical field of chemical synthesis. Fluorine-containing benzoic acid is subjected to a one-pot reaction in a solvent under the action of alkali to obtain fluorine-containing phenate, and fluorine-containing phenol is obtained after acid regulation and dissociation. The synthesis method has the advantages of rich, cheap and easily available raw material structure, short synthesis steps, mild reaction conditions, simple and convenient operation, high synthesis yield, good productquality, wide application range and the like, and is suitable for simple and efficient synthesis of various high-value and high-purity fluorine-containing phenol compounds.
Preparation method 2, 3, 5, 6 - tetrafluoro-phenol
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Paragraph 0020; 0030-0033, (2020/08/09)
The invention discloses a method for preparing 2,3,5,6-tetrafluorophenol. The method comprises the following steps: enabling 2,3,4,5,6-pentafluorobenzoic acid as a raw material to react with inorganicalkali and a phase transfer catalyst in water so as to obtain 4-hydroxy-2,3,5,6-tetrafluorophenol, and performing decarboxylation, thereby obtaining 2,3,5,6-tetrafluorophenol. By adopting the 2,3,4,5,6-pentafluorobenzoic acid as the raw material, the cost of the raw material can be greatly reduced, no special or harsh reaction condition is needed, production equipment is not highly required, nospecial waste is generated, the intermittent is easy to separate, the preparation cost and the labor cost of production can be reduced, and the economic benefits can be increased.
Reaction of polyfluorinated chalcones with guanidine
Borodina,Orlova,Gatilov,Sal'Nikova
, p. 1745 - 1752 (2016/02/03)
Reactions of polyfluorinated chalcones with guanidine in the presence of bases are accompanied by elimination of the polyfluorophenyl group. 3-(Pentafluorophenyl)-1-phenylprop-2-en-1-one and its derivatives reacted with guanidine under basic conditions to give 4-phenylpyrimidin-2-amine, polyfluorobenzenes, and Michael adducts, 3-(2-amino-4-phenylpyrimidin-5-yl)-3-(4-R-2,3,5,6-tetrafluorophenyl)-1-phenylpropan-1-ones. 1-(Pentafluorophenyl)-3-phenylprop-2-en-1-one and 1,3-bis(pentafluorophenyl)prop-2-en-1-one were converted into cinnamic acid derivatives whose reaction with guanidine afforded 2-amino-6-aryl-5,6-dihydropyrimidin-4(1H)-ones.
Catalytic defluorination of perfluorinated aromatics under oxidative conditions using N-bridged diiron phthalocyanine
Colomban, Cédric,Kudrik, Evgenij V.,Afanasiev, Pavel,Sorokin, Alexander B.
supporting information, p. 11321 - 11330 (2014/11/07)
Carbon-fluorine bonds are the strongest single bonds in organic chemistry, making activation and cleavage usually associated with organometallic and reductive approaches particularly difficult. We describe here an efficient defluorination of poly- and perfluorinated aromatics under oxidative conditions catalyzed by the μ-nitrido diiron phthalocyanine complex [(Pc)Fe III(μ-N)FeIV(Pc)] under mild conditions (hydrogen peroxide as the oxidant, near-ambient temperatures). The reaction proceeds via the formation of a high-valent diiron phthalocyanine radical cation complex with fluoride axial ligands, [(Pc)(F)FeIV(μ-N)FeIV(F) (Pc+?)], which was isolated and characterized by UV-vis, EPR, 19F NMR, Fe K-edge EXAFS, XANES, and Kβ X-ray emission spectroscopy, ESI-MS, and electrochemical techniques. A wide range of per- and polyfluorinated aromatics (21 examples), including C6F6, C6F5CF3, C6F5CN, and C6F5NO2, were defluorinated with high conversions and high turnover numbers. [(Pc)FeIII(μ-N)Fe IV(Pc)] immobilized on a carbon support showed increased catalytic activity in heterogeneous defluorination in water, providing up to 4825 C-F cleavages per catalyst molecule. The μ-nitrido diiron structure is essential for the oxidative defluorination. Intramolecular competitive reactions using C6F3Cl3 and C6F3H 3 probes indicated preferential transformation of C-F bonds with respect to C-Cl and C-H bonds. On the basis of the available data, mechanistic issues of this unusual reactivity are discussed and a tentative mechanism of defluorination under oxidative conditions is proposed.
Synthesis of K[4-ROC6F4BF3] from potassium pentafluorophenyltrifluoroborate and O-nucleophiles
Shabalin, Anton Yu.,Adonin, Nicolay Yu.,Bardin, Vadim V.,Prikhod'Ko, Sergey A.,Timofeeva, Maria N.,Bykova, Maria V.,Parmon, Valentin N.
, p. 82 - 87 (2013/05/22)
A new route to potassium polyfluoroaryltrifluoroborates, K[4-ROC 6F4BF3], consisting in the nucleophilic alkoxydefluorination of K[C6F5BF3] with MOR (M = K, Na) in a polar aprotic solvent is suggested. Reaction of K[C 6F5BF3] with KO-t-Bu proceeds smoothly at 25 °C in DME, but the attempted alkoxydefluorination of K[C6F 5BF3] with other NaOR at 30 °C in DME failed. A series of K[4-ROC6F4BF3] (R = Me, Et, Pr, i-Pr, Bu, PhCH2) is prepared using the corresponding sodium alkoxides in DMF at 130 °C in 80-90% isolated yield. Salt K[4-CH2CHCH 2OC6F4BF3] is prepared at 100 °C whereas at 130 °C formation of 2,3,5,6-C6F4HOCH 2CHCH2 occurs. Salt K[4-PhOC6F 4BF3] is obtained in 82% yield using KOPh (2 equivalents) in DMSO at 130 °C.
Selective Reduction of Saturated Perfluorocarbons
Marsella,John A.,Gilicinski, Andrew G.,Coughlin, Anne M.,Pez, Guido P.
, p. 2856 - 2860 (2007/10/02)
Perfluorocycloaliphatic compounds are reduced by solutions of the sodium benzophenone radical anion to give perfluorinated and highly fluorinated aromatic compounds.Perfluorocycloalkanes containing tertiary carbon centers are much more reactive than perfluorocyclohexane.Reduction of perfluoroalkanes and perfluorocycloalkanes that contain perfluoroalkyl substituents proceeds easily; however, it appears that overreduction occurs and no organofluorine products are obtained with these substrates.The selectivity and reactivity of several radical anion reducing agents are strongly correlated with the electrochemical behavior of the reducing agents, the perfluoroalkanes, and the observed perfluoroaromatic reduction products.Direct electrochemical reduction of saturated unsubstituted perfluoroalkanes on an analytical scale was observed for the first time in this work.
REACTION OF POLYFLUORINATED AROMATIC COMPOUNDS WITH SODIUM NITRITE
Miller, A. O.,Furin, G. G.
, p. 317 - 319 (2007/10/02)
The reactions of polyfluorinated aromatic compounds with sodium nitrite lead to the formation of products from N- and O-substitution of the fluorine atoms in the aromatic ring.The increase in the nucleophilic mobility of the fluorine atoms with the introduction of electron-withdrawing substituents into the ring promotes the formation of the O-substitution products.
Reactions of Polyfluoro-arenols and -heteroarenols with Activated Dimethyl Sulphoxide. Facile -Sigmatropic Rearrangement Reactions giving De-aromatised Products
Brooke, Gerald M.,Ferguson, J. A. K. Jamie
, p. 2091 - 2098 (2007/10/02)
Pentafluorophenol reacted with the reagent dimethyl sulphoxide--dicyclohexylcarbodi-imide--orthophosphoric acid below room temperature to give the ether (1), the -rearrangement product (2), and (3) a derivative of (2).Under similar conditions, 2,3,5,6-tetrafluorophenol gave (7) and (8), and 1,3,4,5,6,7,8-heptafluoro-2-naphthol gave (12) and (13).Reaction of polyfluoroarenols with dimethyl sulphoxide--trifluoroacetic anhydride at low temperatures followed by deprotonation with triehylamine resulted in more efficient rearrangement reactions; 4-bromo-3,5,6-trifluoropyridin-2-ol gave the ether (14) and the products of rearrangement both to carbon and nitrogen, (15) (after hydrolysis) and (16) respectively; 2,4,5,6-tetrafluoropyridin-3-ol resulted in the overall replacement of the 2-fluorine by CHO (17) and by CH(SMe)2 (18); and with 2,5,6-trifluoropyrimidin-4-ol and 5-fluoro-4,6-dimethoxypyrimidine-2-ol, simple rearrangement products (21) and (22) were obtained.Hydrolysis of (21) gave the 5-fluorouracil derivative (23).Sodium borohydride reduction and Raney nickel desulphurisations of some of the rearrangement compounds gave phenolic products.Reaction of the sulfone from (13) with base (DBU) effected of the overall efficient replacement of the 1-fluorine in the 2-naphthol by CHO (35) and by CH(SO2Me)2 (36).
