75995-75-4Relevant academic research and scientific papers
Method for preparing hexafluorobutadiene
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Paragraph 0022, (2017/02/23)
The invention discloses a method for preparing hexafluorobutadiene. The method comprises the following steps: carrying out a hydrogenation dechlorination dimerization reaction on 1,1-dichloro-1,2,2-trifluoroethane or 1,2-dichloro-1,1,2-trifluoroethane on a supported metal catalyst in H2 atmosphere, separating out a target product hexafluorobutadiene, carrying out gas phase thermal cracking on an intermediate hydroflurochlorobutane to remove HCl in order to prepare hexafluorobutadiene, filtering the product generated after above reactions, washing the filtered product with an alkali, washing the washed product with water, drying the product, compressing, and carrying out rectifying purification to obtain the highly pure hexafluorobutadiene. The method for preparing hexafluorobutadiene overcomes the disadvantages of long operating period, low unit volume output and large device investment of present technologies, and has the advantages of high yield, few steps, easy industrialization, realization of production of the highly pure hexafluorobutadiene through selection of reactants and control of reaction conditions, simple process, cheap and easily available raw material, low cost, facilitation of industrial production, continuous production, and great improvement of the unit device productivity.
Process for preparing fluorohalogenethers
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Page column 9, (2008/06/13)
A process for preparing (per) fluorohalogenethers having general formula (I):(R)nC(F)mOCAF-CA'F2 wherein:A and A', equal to or different the one from the other, are Cl or Br or one is selected from A and A' and hydrogen and the other is halogen selected from Cl, Br; R = F, or a fluorinated, preferably perfluorinated, substituent, selected from the following groups: linear or branched C1-C20 alkyl more preferably C1-C10; C3-C7 cycloalkyl; aromatic, C6-C10 arylalkyl, alkylaryl; C5-C10 heterocyclic or alkylheterocyclic; when R is fluorinated or perfluorinated alkyl, cycloalkyl, arylalkyl, alkylaryl, it can optionally contain in the chain one or more oxygen atoms;when R is fluorinated it can optionally contain one or more H atoms and/or one or more halogen atoms different from F:n is an integer and is 1 or 2; m = 3-n; by reaction of carbonyl compounds having formula (II):(R)pC(F)q(O) wherein:p is an integer and is 1 or 2; q is an integer and is zero or 1, R is as above; in liquid phase with elemental fluorine and with olefinic compounds having formula (III):CAF=CA'F wherein A and A' are as above, at temperatures in the range from -120°C to -20°C.
Process for preparing fluorohalogenethers
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Page 4-5, (2008/06/13)
A process for preparing (per)fluorohalogenethers having general formula (I): (R)nC(F)mOCAF—CA′F2??(I) wherein: A and A′, equal to or different the one from the other, are Cl or Br or one is selected from A and A′ and hydrogen and the other is halogen selected from Cl, Br; R═F, or a fluorinated, preferably perfluorinated, substituent, selected from the following groups: linear or branched C1-C20 alkyl more preferably C1-C10; C3-C7 cycloalkyl; aromatic, C6-C10 arylalkyl, alkylaryl; C5-C10 heterocyclic or alkylheterocyclic; when R is fluorinated or perfluorinated alkyl, cycloalkyl, arylalkyl, alkylaryl, it can optionally contain in the chain one or more oxygen atoms; when R is fluorinated it can optionally contain one or more H atoms and/or one or more halogen atoms different from F: n is an integer and is 1 or 2; m=3-n; by reaction of carbonyl compounds having formula (II): (R)pC(F)q(O)??(II) wherein: p is an integer and is 1 or 2; q is an integer and is zero or 1, R is as above; in liquid phase with elemental fluorine and with olefinic compounds having formula (III): CAF═CA′F??(III) wherein A and A′ are as above, at temperatures in the range from ?120° C. to ?20° C.
Heterocyclic Polyfluoro-compounds. Part 31. Photochemical Oxetan Formation from Fluoroketones and Perfluoroaldehydes and 1,2-Difluoroethylene
Barlow, Michael G.,Coles, Barrie,Haszeldine, Robert N.
, p. 2258 - 2267 (2007/10/02)
The photochemical addition of five fluoroketones (hexafluoro-, chloropentafluoro-, 1,3-dichlorotetrafluoro-, 1,1,3-trichlorotrifluoro-, and 1,1,1-trifluoro-propan-2-one) and the perfluoroaldehydes RFCHO (RF=CF3, C2F5, or n-C3F7) to (Z)- or (E)-1,2-difluoroethylene at λ > 300 nm has been studied.Oxetan formation dominates with hexafluoropropan-2-one, but there is increasing competition from reactions involving free radicals arising from photolysis of the ketone as the chlorine content is increased.Oxetan formation occurs with little stereospecificity.The aldehydes give r-2-perfluoroalkyl-t-3,c-4-, and -c-3,t-4-, and -t-3,t-4-difluoro-oxetans, in the ratio 1.0 : 1.7 +/- 0.2 : 1.3 +/- 0.1, respectively, and in high yield (78-94percent).A small amount of olefin isomerisation occurred. Flow pyrolysis of the oxetans from hexafluoroacetone yields (Z)- and (E)-1,2-difluoroethylene and the olefin (CF3)2C=CHF, the oxetan yields the olefins (Z)- and (E)-CHF=CHF and (CF2Cl)2C=CHF, and r-2-pentafluoroethyl- or heptafluoro-n-propyl-c-3,t-4-difluoro-oxetans yield mainly the olefins (Z)- and (E)-RFCHC=CHF (RF=C2F5 or n-C3F7).
