- Synthesis method of 2-chloro-1, 4-dibromo-1, 1, 2-trifluorobutane
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The invention belongs to the field of fluorine-containing fine chemical engineering, and provides a synthesis method of 2-chlorine-1, 4-dibromo-1, 1, 2-trifluorobutane. Specifically, 1, 2-dibromo-1-chloro-1, 2, 2-trifluoroethane is used as a solvent, and the 1, 2-dibromo-1-chloro-1, 2, 2-trifluoroethane reacts with ethylene in the presence of a free radical initiator containing tert-butyl peroxybenzoate (TBPB), benzoyl peroxide (BPO), lauroyl peroxide (LPO) and the like. The reaction temperature is 70-130 DEG C, and preferably, the reaction temperature is 90-120 DEG C. The molar ratio of 1, 2-dibromo-1-chloro-1, 2, 2-trifluoroethane to the initiator is 1: (0.5-1). The method reduces the content of 1, 6-dibromo-2-chloro-1, 1, 2-trifluorohexane, has the advantages of cleanness, safety and no need of solvent recovery, and is mainly used for synthesis of 2-chloro-1, 4-dibromo-1, 1, 2-trifluorobutane.
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Paragraph 0017-0020
(2021/04/28)
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- Rearrangement of 3-membered 1,1,2-trifluorobromonium and iodonium ions and comparison of trifluorochloronium to fluorocarbenium ions
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(Chemical Equation Presented) Reactions of chlorine (Cl2) with 4-halo-1,1,2-trifluorobut-1-enes (1, 2, or 3) give open-ion intermediates A and E that are in equilibrium. The open-chloronium ions (E) rearrange to a five-membered-ring halonium ion during ionic chlorination of 3 when the number-4 halo-substituent is iodine. Three-membered-ring bromonium and iodonium ions from alkenes 1, 2, or 3 are rather symmetrical and similar in structure. Quantum chemical calculations show that five-membered-ring halonium ion intermediates are 11 to 27 kcal/mol more stable than the three-membered-ring halonium ions or the open-ions A and E. The five-membered-ring intermediates lead to rearranged products. Rearranged products increase as the number-4 halogen (Z) becomes more nucleophilic (Z: Cl Br I). Open chloronium ions from ionic chlorination of terminal fluorovinyl alkenes are compared to the open ions generated by protons to similar alkenes.
- Shellhamer, Dale F.,Davenport, Kevyn J.,Forberg, Heidi K.,Herrick, Matthew P.,Jones, Rachel N.,Rodriguez, Sean J.,Sanabria, Sunamita,Trager, Nicole N.,Weiss, Ryan J.,Heasley, Victor L.,Boatz, Jerry A.
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p. 4532 - 4538
(2008/09/20)
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- Copper salt-catalysed reaction of perfluoroalkyl halides with olefins
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Perfluoroalkyl halides react with olefins in the presence of copper acetate and hydrazine to give 1,2-addition products.
- Igumnov, Sergei M.,Don, Veronika L.,Vyazkov, Vladimir A.,Narinyan, Karen E.
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p. 189 - 190
(2007/10/03)
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