| 20090247791 | PROCESS FOR THE PREPARATION OF FLUOROMETHYL 2,2,2-TRIFLUORO-1-(TRIFLUOROMETHYL) ETHYL ETHER - 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. | 10-01-2009 |
