- Method of making 1,1,3,3,3-pentafluoropropene
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The invention provides an economic process for the manufacture of the hydrofluorocarbon 1,1,3,3,3-pentafluoropropene (HFC-1225zc). HFC-1225zc can be made from the dehydrochlorination of 1-chloro-1,1,3,3,3-pentafluoropropane (HCFC-235fa). Alternatively, HFC-1225zc can also be made from the dehydrofluorination of 1,1,1,3,3,3-hexafluoropropane (HFC-236fa). HFC-1225zc) is a compound that has the potential to be used as a low Global Warming Potential refrigerant, blowing agent, aerosol propellant, or solvent.
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Page/Page column 4
(2008/06/13)
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- Method of producing 1,1,1,3,3-pentafluoropropane, a method of producing 1,1,1,3,3-pentafluoro-2-halogeno-3-chloropropane, and a method of producing 1,1,1,2,3,3-hexachloropropene
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There are provided production methods of 1,1,1,3,3-pentafluoropropane characterized in that 1,1,1,3,3-pentafluoro-2,3-dichloropropane is reacted with hydrogen fluoride in the presence of a noble metal catalyst; of 1,1,1,3,3-pentafluoro-2-halogeno-3-chloropropane characterized in that the halogenated propene indicated as general formula I is fluorinated in the presence of antimony trihalogenide and/or antimony pentahalogenide by hydrogen fluoride of mole ratio of or over five times the said antimony halogenide in a liquid phase; and of 1,1,1,2,3,3-hexaohloropropene characterized in that 1,1,1,2,2,3,3-heptachloropropane is reacted with an aqueous solution of alkali metal hydroxide in the presence of a phase transfer catalyst. Therefore, an industrial manufacturing method which is possible to obtain the objective product easily at low cost and high yield can be provided.
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- PHOTOCHEMICAL REDUCTION OF CARBON-HALOGEN BONDS. 3. REGIOSELECTIVITY OF THE REACTION IN FLUORINATED HALOGENOPROPANOATES.
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The ester group exhibits a strong directive effect in the photochemical reduction of a carbon-halogen bond and directs the reduction in perhalogenated chlorofluoropropanoates of the type CFXY-CClZ-COOR (X,Y,Z = Cl, F) to the α-position in the acyl part of an ester.The reduction takes place with the same regioselectivity even in esters CFCl2-CHCl-COOR (10).In esters containing an α -CCl2- group the reductions to the first and the second stages can be separated and the individual reduction products can be obtained preparatively.The α C-F bond is more difficult to reduce and therefore in the ester CFCl2-CHF-COOR (11) the β C-Cl bond was reduced specifically and in the ester CF2Cl-CHF-COOR (12) both the α C-F bond and the β C-Cl bond were reduced parallely.The relative reactivity of fluorinated halogenopropanoates with an α C-Cl bond showed only small differences in the reduction with 2-propanol in the presence of acetone as a sensitiser; the quantum yield Φ reached values of about 28-35 under kinetic measurements and thus proved the existence of a chain radical mechanism.
- Paleta, O.,Dadak, V.,Dedek, V.,Timpe, H.-J.
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p. 397 - 414
(2007/10/02)
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- TWO ROUTES OF PROPENE CONVERSION INTO PERCHLORO DERIVATIVES BY THE ACTION OF HYDROGEN CHLORIDE AND OXYGEN.
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Destructive catalytic conversions of propene by the action of hydrogen chloride and oxygen are of complex character and may proceed by several routes, depending on the oxygen and hydrogen chloride contents in the reactants. Elucidation of the character of these routes is of practical interest, and is necessary for selection of the process conditions. In view of this , the influence of the hydrogen chloride:propene ration on the process was studied in the ranges from 0 to 6 (contract time 2 sec) and from 6 to 12 (contact time 5 sec) at the constant stoichiometric ratio HCl:O//2 equals 2. The interaction of propene with hydrogen chloride at HCl:C//3H//6 ratios from 6 to 12 (Fig. lb) has certain peculiarities, with chlorinolysis of hexachloropropene. However, at HCl:C//3H//6 ratios from 9 to 10. 5 acrolein is formed and then converted into various compounds with evolution of the corresponding amounts of carbon monoxide. It is shown that the conversions of propene into various compounds proceed by two routes, with intermediate formation of allyl chloride and acrolein.
- Potapov
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p. 1773 - 1774
(2007/10/02)
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- Process for the preparation of 4,5-dichloro-1,2-dithiacyclopenten-3-one
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An improved process for preparation of 4,5-dichloro-1,2-dithia-cyclopenten-3-one of the formula STR1 by reacting hexachloroprene with sulphur at elevated temperatures, wherein the improvement comprises hydrolyzing by-product sulphur chlorides by conducting the reaction in the presence of water.
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