- Production of fluormethyl 2,2,2-trifluoro-1-(trifluoromethyl)ethyl ether
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A process for removing water from a mixture comprising hydrogen fluoride and water, said process comprising: a) providing a mixture comprising hydrogen fluoride and water; and b) removing water from the mixture as a constant boiling mixture with hydrogen fluoride.
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Paragraph 0051-0053
(2015/09/28)
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- PROCESS FOR THE PREPARATION OF CHLOROMETHYL 2,2,2-TRIFLUORO-1-(TRIFLUOROMETHYL) ETHYL ETHER
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The present invention refers to a process for the preparation of chloromethyl 2,2,2-trifluoro-1-(trifluoromethyl) ethyl ether (sevochlorane), which consists of reacting hexafluoroisopropanol with: a formaldehyde equivalent selected between paraformaldehyde or 1,3,5-trioxane, a chlorinating agent selected from the group consisting of oxalyl chloride, phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride, sulfuryl chloride and thionyl chloride, and a strong acid selected from the group consisting of concentrated or fuming sulfuric acid. Said process provides sevochlorane in high purity and yield, which can be converted to sevoflurane by known means.
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Page/Page column 17-21
(2008/06/13)
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- PROCESS FOR THE PREPARATION OF FLUOROMETHYL 2,2,2-TRIFLUORO-1-(TRIFLUOROMETHYL) ETHYL ETHER
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The present invention refers to a process for the preparation of fluoromethyl 2,2,2-trifluoro-1-(trifluoromethyl) ethyl ether (sevoflurane) which includes a step that consists of reacting hexafluoroisopropanol with a formaldehyde equivalent selected among paraformaldehyde or 1,3,5-trioxane, a chlorinating agent selected from the group consisting of oxalyl chloride, phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride, sulfuryl chloride and thionyl chloride, and a strong acid selected from the group consisting of concentrated or fuming sulfuric acid resulting in the formation of the intermediate sevochlorane which is converted to sevoflurane in a second step which consists of reacting sevochlorane with an alkali metal fluoride, or a linear or branched chain tetra-alkyl quarternary ammonium fluoride in the presence of a sub-stoichiometric quantity of an alkali metal iodide, or a linear or branched alkyl chain tetra-alkyl quarternary ammonium iodide, preferably in a solvent.
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Page/Page column 20-22
(2008/06/13)
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