594-91-2Relevant articles and documents
Preparation method for perfluoroalkane
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Paragraph 0034; 0035, (2016/11/28)
The invention discloses a preparation method for perfluoroalkane. The preparation method comprises the following steps: adding a fluorination reagent into a reaction vessel, stirring the fluorination reagent at room temperature, introducing fluorine-nitrogen gas mixture into the reaction vessel for activation of the fluorination reagent and continuing stirring for half an hour, wherein the concentration of fluorine gas in the fluorine-nitrogen gas mixture is 0.5 to 10%, and the molar weight of the fluorine-nitrogen gas mixture is 1 to 5% of the molar weight of the fluorination reagent; after completion of stirring, relieving residual pressure in the reaction vessel, and adding perfluoroalkyl halide and a solvent into the reaction vessel for a reaction at 150 to 200 DEG C for 5 to 10 h, wherein a mol ratio of perfluoroalkyl halide to the fluorination reagent is (1: 1) to (1: 2), and a mol ratio of perfluoroalkyl halide to the solvent is (1: 5) to (1: 15); and after a reaction product is obtained upon completion of the reaction, cooling the reaction product to room temperature and distilling the reaction product to obtain perfluoroalkane. The method provided by the invention has the advantages of simple equipment, high operation security, etc.
Aerosol Direct Fluorination: Alkyl Halides. 2. Chlorine Shift and the Stability of Radicals
Adcock, James L.,Evans, William D.
, p. 2719 - 2723 (2007/10/02)
Unlike alkyl bromides and iodides, alkyl chlorides are shown to be stable to direct fluorination, even under ultraviolett irradiation, at temperatures of 30 deg C and below.Although less reactive than the bromides and iodides, F-alkyl chlorides may be derivatized, presenting another example of direct fluorination-survivable functionality.High (63 percent) to moderate (32 percent) isolated yields of the analogous perfluororalkyl chlorides can be synthesized by aerosol direct fluorination of 1-chloropropane, 1-chlorobutane, 1-chloro-2-methylpropane, 1-chloro-3-methylbutane, 1-chlo-ro-2-methylbutane, and chlorocyclopentane with generally less than 20 percent C-C bond cleavage.Tertiary alkyl chlorides generally undergo intramolecular 1,2-chloride shift in the earliest stages of reaction in a manner characteristic of β-chloro radicals forming principally primary F-alkyl chlorides.Thus 2-chloro-2-methylpropane produces 1-chloro-F-2-methylpropane (47 percent), and 2-chloro-2-methylbutane produces a 16:6.3:1 ratio of 1-chloro-F-2-methylbutane, 1-chloro-F-3-methylbutane, and 2-chloro-F-3-methylbutane, respectively, in 32 percent combined yield.Secondary alkyl chlorides undergo a similar but incomplete rearrangement producing mixtures of primary and secondary F-alkyl chlorides.Thus 2-chloropropane produces a 2:1 mixture of 2-chloro-F-propane and 1-chloro-F-propane in 50 percent combined yield; 2-chlorobutane produces a 1:1.5 mixture of 2-chloro-F-butane and 1-chloro-F-butane in 34 percent combined yield, and 3-chloropentane produces a 2:3:1 mixture of 3-chloro-F-pentane, 2-chloro-F-pentane, and 1-chloro-F-pentane, respectively, in a combined yield of 30 percent.Because secondary alkyl chlorides partially rearrange but primary alkyl chlorides donot rearrange at all on fluorination, doubt is cast on the postulate that the intermediate radicals are equilibrating.
REACTIONS OF TETRAFLUOROETHYLENE OLIGOMERS. PART 1. SOME PYROLYTIC REACTIONS OF THE PENTAMER AND HEXAMER AND OF THE FLUORINE ADDUCTS OF THE TETRAMER AND PENTAMER
Coe, Paul L.,Sellers, Simon F.,Tatlow, John Colin
, p. 417 - 440 (2007/10/02)
Pyrolyses of these highly branched fluorocarbons over glass beads caused the preferential thermolyses of C-C bonds where there is maximum carbon substitution.Fluorinations of perfluoro-3,4-dimethylhex-3-ene (tetramer) (I) and perfluoro-4-ethyl-3,4-dimethylhex-2-ene (pentamer) (II) over cobalt (III) fluoride at 230 deg C and 145 deg C respectively afforded the corresponding saturated fluorocarbons (III) and (IV), though II gave principally the saturated tetramer (III) at 250 deg C.Pyrolysis of III alone at 500-520 deg C gave perfluoro-2-methylbutane (V), whilst pyrolysis of III in the presence of bromine or toluene afforded 2-bromononafluoorobutane (VI) and 2H-nonafluorobutane (VII) respectively.Pyrolysis of perfluoro-3-ethyl-3,4-dimethylhexane (IV) alone gave a mixture of perfluoro-2-methylbutane (V), perfluoro-2-methylbut-1-ene (VIII), perfluoro-3-methylpentane (IX), perfluoro-3,3-dimethylpentane (X), and perfluoro-3,4-dimethylhexane (III).Pyrolysis of IV in the presence of bromine gave (VI) and 3-bromo-3-trifluoromethyldecafluoropentane (XI): with toluene, pyrolysis gave VII and 3H-3-trifluoromethyldecafluoropentane (XII).Pyrolysis of II at 500 deg C over glass gave perfluoro-1,2,3-trimethylcyclobutane (XIII) and perfluoro-2,3-dimethylpenta-1,3(E)- and (Z)-diene (XIV) and (XV) respectively.The diene mixture (XIV and XV) was fluorinated with CoF3 to give perfluoro-2,3-dimethylpentane (XVI) and was cyclised thermally to give the cyclobutene (XIII).Pyrolysis of perfluoro-2-(1'-ethyl-1'-methylpropyl)-3-methylpent-1-ene (XVII) (TFE hexamer major isomer) at 500 deg C gave perfluoro-1-methyl-2-(1'-methylpropyl)cyclobut-1-ene (XVIII) and perfluoro-2-methyl-3-(1'-methylpropyl)buta-1,3-diene (XIX).Fluorination of XVIII over CoF3 gave perfluoro -1-methyl-2-(1'-methylpropyl)cyclobutane (XX), which on co-pyrolysis with bromine gave VI.XIX on heating gave XVIII.Reaction of XVIII with ammonia in ether gave a mixture of E and Z 1-trifluoromethyl-2-(1'-trifluoromethylpentafluoropropyliden-1'-yl)tetrafluorocyclobutylamine (XXI) which on diazotisation and hydrolysis afforded 2-(2'trifluoromethyltetrafluorocyclobut-1-en-1'-yl)-octafluorobutan-2-ol (XXII).
