- METHOD FOR PRODUCING HALOGENATED ETHER
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PROBLEM TO BE SOLVED: To provide a method for producing 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether (isoflurane) or 1,2,2,2-tetrafluoroethyl difluoromethyl ether (desflurane) useful as an inhaled anesthetic, on an industrial scale with high efficie
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Paragraph 0114; 0115
(2020/03/05)
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- Synthetic and mechanistic aspects of halo-F-methylphosphonates
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The synthesis of a variety of new halo-F-methylphosphonates has been achieved by a Michaelis-Arbuzov type reaction between a halo-F-methane and a trialkyl phosphite. This synthesis has proved to be of wide scope and utility for the high yield preparation of a number of heretofore unknown compounds. The 1H, 19F, 13C and 31P NMR spectroscopic properties are reported in detail. The mechanism for the formation of bromodifluoromethylphosphonates has been shown to proceed through the intermediacy of difluorocarbene:CF2. The phosphonate products have been shown to react with a wide variety of reagents. Fluoride and alkoxide ions react by attack at phosphorus with cleavage of the carbon-phosphorus bond and formation of [:CF2] from the bromodifluoromethylphosphonates and the CFBr2- anion from the dibromofluoromethylphosphonates. Iodide ion and tertiary phosphines react by attack at the ester carbon to give stable phosphonate salts. Hydrolysis of the phosphonate esters with 50% aqueous HCl gives the expected phosphonic acids. Trimethylsilyl bromide attacks phosphoryl oxygen to afford the bis(trimethylsilyl) esters.
- Flynn, Richard M.,Burton, Donald J.
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experimental part
p. 815 - 828
(2011/10/08)
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- Insertion reactions of difluorocarbene generated by pyrolysis of hexafluoropropene oxide to O-H bond
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ROCHF2-type fluorinated ethers were synthesized by the reaction of hexafluoropropene oxide (HFPO) with alcohol or phenol. In this reaction, although the insertion reaction of difluorocarbene to OH bond and the nucleophilic attack of alcohol or
- Mizukado, Junji,Matsukawa, Yasuhisa,Quan, Heng-Dao,Tamura, Masanori,Sekiya, Akira
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p. 373 - 377
(2007/10/03)
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- Compositions of a hydrofluoroether and a hydrofluorocarbon
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This invention relates to compositions that include at least one fluoroether and at least one hydrofluorocarbon. Included in this invention are compositions of a cyclic or acyclic hydrofluoroether of the formula CaFbH2a+2?bOc wherein a=2 or 3 and 3≦b≦8 and c=1 or 2 and a hydrofluorocarbon of the formula CnFmH2n+2?m wherein 1≦n≦4 and 1≦m≦8. Such compositions may be used as refrigerants, cleaning agents, expansion agents for polyolefins and polyurethanes, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, and displacement drying agents.
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Page/Page column 5
(2008/06/13)
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- A SIMPLE CONVENIENT METHOD FOR PREPARATION OF DIFLUOROMETHYL ETHERS USING FLUOROSULFONYLDIFLUOROACETIC ACID AS A DIFLUOROCARBENE PRECURSOR
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In the presence of catalytic amounts of sodium sulfate or cuprous iodide, a variety of alkyl and aryl difluoromethyl ethers were synthesized in moderate yields by the reaction of the corresponding alcohols and phenols with fluorosulfonyldifluoroacetic acid (1) in acetonitrile under mild conditions.Fluorosulfonyldifluoroacetate anion (5) is believed to readily eliminate SO2, CO2 and F(1-), thus liberating CF2:; insertion of difluorocarbene into O-H bonds and its capture by fluorode ion then result in the formation of ethers and by-product CF3H, respectively.
- Chen, Qing-Yun,Wu, Sheng-Wen
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p. 433 - 440
(2007/10/02)
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