- PROCESS FOR THE PREPARATION OF TETRAFLUOROPROPENE
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A process for producing at least one tetrafluoropropene, the process comprising (i) converting Z-1233zd to TFMA in the presence of at least one base, wherein the process is conducted in the presence of water, and (ii) contacting the TFMA produced in step (i) with hydrogen fluoride (HF) in the presence of a Lewis acid metal halide catalyst to produce reaction product comprising at least one tetrafluoropropene.
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Page/Page column 8
(2016/09/15)
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- Chemoselective halogenation of 2-hydroperfluoroalkyl aldehydes
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2-Hydroaldehydes, RfCH(R)CHO, where Rf = CF 3, C2F5, n-C3F7 and R = CF3, C2F5, n-C3F7, Ph, H, were prepared via acid hydrolysis of the corresponding vinyl ethers, R fC(R) = CHOCH3, which can be readily prepared by reaction of Ph3P+C?HOCH3 with the corresponding ketone. The 2-hydroaldehydes can be chemoselectively converted to the acyl halide, RfCH(R)C(O)X (X = Cl, Br), via free-radical halogenation. The perfluoroalkyl group deactivates the 2-position toward radical abstraction of the 2-hydrogen, and halogenation occurs exclusively at the formyl hydrogen. However, halogenations of the 2-hydroaldehydes in glacial acetic acid chemoselectively gives the 2-haloaldehydes, RfCX(R)CHO, X = Cl, Br. Hydrolysis of the 2-hydroperfluoroacyl halides provides a useful route to 2-hydroperfluoroalkyl branched carboxylic acids, useful ketene precursors. This route avoids the use of toxic fluoroolefins, such as perfluoroisobutylene.
- Wiebe, Donald A.,Burton, Donald J.
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experimental part
p. 4 - 11
(2012/07/13)
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- Convenient synthesis of 3,3,3-trifluoropropanoic acid by hydrolytic oxidation of 3,3,3-trifluoropropanal dimethyl acetal
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A convenient and efficient method for preparing 3,3,3-trifluoropropanoic acid (1) is reported. The starting material is 1-chloro-3,3,3-trifluoropropene (2) that can be easily transformed into 3,3,3-trifluoropropanal dimethyl acetal (4) on treatment with methanol and KOH followed by acid-catalyzed addition of methanol. Direct transformation of 4 into 1 was efficiently achieved with 30% aqueous hydrogen peroxide (4.0 equiv.) in the presence of FeCl3 (0.025 equiv.) and hydrochloric acid (0.5 equiv.).
- Komata, Takeo,Akiba, Shinya,Hosoi, Kenji,Ogura, Katsuyuki
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- A novel and convenient synthesis of (Z)-3,3,3-trifluoropropenyl alkyl ethers and CF3-substituted propyl acetals as versatile CF3-containing building blocks
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A novel and convenient preparation of (Z)-3,3,3-trifluoropropyl alkyl ethers and their further transformation into CF3-substituted propyl acetals is described.
- Hong, Feng,Hu, Chang-Ming
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