- Photochemistry of Anhydrides Part 4.-Photolysis of Perfluoro-n-butyric Anhydride Reaction of n-C3F7 Radicals with Cyclohexane
-
The photolysis of the vapour of perfluoro-n-butyric anhydride was studied at 20 and 227 deg C.The effective primary process is (n-C3F7CO)2O+hυ -> 2 n-C3F7+CO+CO2 and the overall decomposition is quantitatively described by the equation (n-C3F7CO)2O+hυ -> n-C6F14+CO+CO2.The quantum yields of products increase with temperature but are independent of pressure. (n-C3F7CO)2O was photolysed in the presence of cyclohexane vapour.For the reactions n-C3F7+c-C6H12 -> n-C3F7H+c-C6H11 kH 2n-C3F7 -> C6F14 kc we obtain, log kH/k1/2c = (4.99+/-0.12)-(23910+/-750)/Θ where Θ = 2.303RTJmol-1 and kH/k1/2c is in cm1/2mol-1/2s-1/2.
- Stock, Colin J.,Whittle, Eric
-
-
Read Online
- HETEROCYCLIC POLYFLUORO-COMPOUNDS. PART 35. DEHYDROFLUORINATION OF 2,2-BIS(TRIFLUOROMETHYL)- AND 2-PERFLUOROALKYL-3,4-DIFLUORO-OXETANS
-
Solid potassium hydroxide dehydrofluorinates 2,2-bis-(trifluoromethyl)-3,4-difluoro-oxetan to 3-fluoro-4,4-bis-(trifluoromethyl)-2-oxete (59percent), 2-pentafluoroethyl-3,4-difluoro-oxetan to 2-tetrafluoroethylidene-3,4-difluoro-oxetan, and r-2-heptafluoro-n-propyl-t-3,t-4-difluoro-oxetan to (Z)-2-hexafluoro-n-propylidene-cis-3,4-difluoro-oxetan.Factors which affect these reactions are discussed.
- Barlow, M. G.,Coles, B.,Haszeldine, R. N.
-
-
Read Online
- Perfluoroalkyl Grignard Reagents: NMR Study of 1-Heptafluoropropylmagnesium Chloride in Solution
-
We report on the generation of a perfluoroalkyl Grignard reagent (FRMgX) by exchange reaction between a perfluoroalkyl iodide (FR-I) and a Grignard reagent (RMgX). 19F NMR was applied to monitor the generation of n-C3F7MgCl. Additional NMR techniques, including 19F COSY, NOESY, and pulsed gradient spin-echo (PGSE) diffusion NMR, were invoked to assign peaks observed in 19F spectrum. Schlenk equilibrium was observed and was significantly influenced by solvent, diethyl ether, or THF.
- Guang, Jie,Hopson, Russell,Williard, Paul G.,Fujiu, Motohiro,Negishi, Kazuyuki,Mikami, Koichi
-
p. 5922 - 5928
(2016/07/23)
-
- METHOD AND APPARATUS FOR CONTINUOUSLY PRODUCING 1,1,1,2,3-PENTAFLUOROPROPANE WITH HIGH YIELD
-
A method and apparatus for method of continuously producing 1,1,1,2,3-pentafluoropropane with high yield is provided. The method includes (a) bringing a CoF3-containing cobalt fluoride in a reactor into contact with 3,3,3-trifluoropropene to produce a CoF2-containing cobalt fluoride and 1,1,1,2,3-pentafluoropropane, (b) transferring the CoF2-containing cobalt fluoride in the reactor to a regenerator and bringing the transferred CoF2-containing cobalt fluoride into contact with fluorine gas to regenerate a CoF3-containing cobalt fluoride, and (c) transferring the CoF3-containing cobalt fluoride in the regenerator to the reactor and employing the transferred CoF3-containing cobalt fluoride in Operation (a). Accordingly, the 1,1,1,2,3-pentafluoropropane can be continuously produced with high yield from the 3,3,3-trifluoropropene using a cobalt fluoride (CoF2/CoF3) as a fluid catalyst, thereby improving the reaction stability and readily adjusting the optimum conversion rate and selectivity.
- -
-
Paragraph 0110-0111
(2014/05/20)
-
- Compositions
-
A composition comprising HCFO-1233xf and at least one additional compound selected from the group consisting of HCFO-1233zd, HCFO-1232xd, HCFO-1223xd, HCFC-253fb, HCFC-233ab, HFO-1234yf, HFO-1234ze, ethylene, HFC-23, CFC-13, HFC-143a, HFC-152a, HFO-1243zf, HFC-236fa, HCO-1130, HCO-1130a, HFO-1336, HCFC-244bb, HCFC-244db, HFC-245fa, HFC-245cb, HCFC-133a, HCFC-254fb, HCFC-1131, HCFO-1242zf, HCFO-1223xd, HCFC-233ab, HCFC-226ba, and HFC-227ca.
- -
-
Paragraph 0104; 0105
(2013/09/12)
-
- Me3SiCF3/AgF/Cu - A new reagents combination for selective trifluoromethylation of various organic halides by trifluoromethylcopper, CuCF3
-
An alternative copper halide-free route to obtain highly reactive trifluoromethylcopper species has been developed via the reaction of silver fluoride and trimethyl(trifluoromethyl)silane followed by a redox transmetallation with elemental copper. The composition of the reactive intermediate was investigated by means of UV/Vis/NIR, ESR, 19F NMR spectroscopy and ESI mass spectrometry. "Trifluoromethylcopper" prepared by the oxidative transmetallation route exhibits excellent reactivity and selectivity in substitutions of iodine or bromine bond to aromatic or heterocyclic compounds for trifluoromethyl groups without any additional catalyst.
- Kremlev, Mikhail M.,Mushta, Aleksej I.,Tyrra, Wieland,Yagupolskii, Yurii L.,Naumann, Dieter,M?ller, Angela
-
body text
p. 67 - 71
(2012/03/10)
-
- PROCESSES FOR THE PRODUCTION OF FLUOROPROPANES AND HALOPROPENES
-
A process is disclosed for making CF3CF2CH3, CF3CF=CH2 and/or CF3CCI=CH2. The process involves reacting at least one starting material selected from the group consisting of halopropanes of the formula CX3CH2CH2X, halopropenes of the formula CX3CH=CH2 and halopropenes of the formula CX2=CHCH2X, wherein each X is independently F or Cl, with HF and CI2 in a reaction zone to produce a product mixture comprising HF, HCI, CF3CF2CH3, CF3CF=CH2, and CFsCCI=CH2; and recovering the CF3CF2CH3, CF3CF=CH2 and/or CFsCCI=CH2 from the product mixture. Also disclosed is a process for making CF3CH2CHF2, CFsCH=CHF, and/or CFaCH=CHCI. This process involves reacting at least one starting material selected from the group consisting of halopropenes of the formula CX3CH=CH2 and halopropenes of the formula CX2=CHCH2X, wherein each X is independently F or Cl, with HF and CI2 in a reaction zone to produce a product mixture comprising HF, HCI, CF3CH2CHF2, CFsCH=CHF and CF3CH=CHCI; and recovering the CF3CH2CHF2, CFsCH=CHF, and/or CF3CH=CHCI from the product mixture. The molar ratio of HF to the total amount of starting materials fed to the reaction zone for both of these processes is at least stoichiometric, and the molar ratio of Cl2 to total amount of starting material fed to the reaction zone for both of these processes is 2:1 or less.
- -
-
Page/Page column 15-17
(2008/12/05)
-
- Reactions of epoxides derived from internal perfluoroolefins with o-phenylenediamine and 2-aminophenol
-
The reactions of epoxy derivatives of internal perfluoroolefins with o-phenylenediamine and 2-aminophenol in dioxane gave 23-67% of the corresponding 2,3-bis(perfluoroalkyl)quinoxalines and 2,3-bis-(perfluoroalkyl)-2H-1,4- benzoxazin-2-ols, respectively. When N,N-dimethylacetamide was used as a solvent, the main reaction pathway was anionic isomerization of epoxides into ketones which were then converted into 2-perfluoroalkylbenzimidazoles (in the reactions with o-phenylenediamine) or 2-hydroxy-N-perfluoroalkanoylanilines (in the reactions with 2-aminophenol). The reaction of 3,4-epoxydodecafluorohexane with 2-aminophenol in N,N-dimethylacetamide was accompanied by unusual cyclization to afford 2-pentafluoropropanoyl-2-pentafluoroethyl-1,3- benzoxazolidine. Pleiades Publishing, Inc., 2006.
- Saloutina,Zapevalov,Saloutin,Kodess,Kirichenko,Pervova,Chupakhin
-
p. 558 - 566
(2007/10/03)
-
- Fluorine chemistry - Wittig based synthesis of volatile organofluorine compounds
-
A simple and practical method has been developed for the synthesis and characterization of several interesting classes of volatile organofluorine compounds from fluorophosphonium salts via their in situ generated corresponding ylides. The fluorinated phosphonium ylides react with hexafluoroacetone in DMF to generate perfluoroisobutylene, whereas in the presence of bromine or iodine containing electrophiles, tetrafluoroethylene, perfluoro-2-butene, perfluorocyclobutane, and 1H-heptafluoropropane are obtained.
- Bhadury, Pinaki S.,Singh, Sapna,Sharma, Mamta,Palit, Meehir,Jaiswal, Devendra K.
-
p. 1186 - 1191
(2007/10/03)
-
- Addition of some unreactive fluoroalkanes to tetrafluoroethylene.: Direct catalytic synthesis of F-butene-2
-
Condensation of trifluoromethanes, CF3X (X=H, Cl, Br, I), with tetrafluorethylene to form the corresponding F-n-propyl adducts have been carried out with aluminum chlorofluoride as catalyst. Yields of C3F7I and C3F7Br are especially good, making these useful perfluoropropyl intermediates readily available. Details of the reactions, especially the presence of low percentages of perfluoroisopropyl iodide and bromide in the products, are accounted for by proposed mechanisms involving halonium intermediates. Longer-chain primary iodides can also be added to tetrafluoroethylene, but the final products are predominantly fluoroolefins, with pentafluoroethyl iodide as a byproduct. In the case of the addition of C2F5I to tetrafluoroethylene, conditions for an efficient, low temperature dimerization of terafluoroethylene to F-butene-2 catalyzed by a combination of C2F5I/aluminum chlorofluoride have been defined. Evidence for an unusual transfer of I+ from the iodonium derivative of F-butene-2 to tetrafluoroethylene is presented.
- Petrov, Viacheslav A.,Krespan, Carl G.
-
p. 199 - 204
(2007/10/03)
-
- High-yield, radical-initiated oxidative functionalization of ethane by perfluorocarboxylic acid anhydrides. Role of metal ions in catalytic alkane oxidations in the presence of perfluorocarboxylic acid anhydrides
-
Hydrogen peroxide and a trace of either ethene or propene initiated the conversion of ethane to propionic acid and its mixed anhydride (CH3CH2CO2H + CH3CH2COOCOCF3) and trifluoromethyl ethyl ketone, CH3CH2COCF3, by trifluoroacetic anhydride at 80 °C. For a fixed amount of H2O2, the amount of products formed increased with increasing amount of trifluoroacetic anhydride employed and was always higher than the amount of H2O2 added. These products were also obtained when H2O2 was replaced by other radical initiators: m-chloroperbenzoic acid, azobisisobutyronitrile, and PbEt4. With PbEt4, ethene or propene was not required for product formation and close to 500 equiv of products was formed for every equivalent of PbEt4 employed! Longer chain perfluorocarboxylic acid anhydrides reacted analogously; however, as the R(f) group increased in length, a corresponding increase in mixed anhydride to ketone selectivity was observed. Methane gave very little product under the reaction conditions whereas propane underwent simple stoichiometric oxidation to 2-propanol and acetone by H2O2. The addition of (CF3CO2)2Pd to the ethane reaction resulted in simple oxidation to ethanol and acetaldehyde in amounts lower than that corresponding to the H2O2 present. In complete contrast to the ethane reaction, the yield of products from methane increased significantly (although less than the H2O2 added) upon the addition of (CF3CO2)2Pd, with methanol being the principal product.
- Hogan, Terrence,Sen, Ayusman
-
p. 2642 - 2646
(2007/10/03)
-
- Sodium Perfluoroalkane Carboxylates as Sources of Perfluoroalkyl Groups
-
Sodium trifluoroacetate, in the presence of copper(I) iodide, is used as a source of trifluoromethyl to replace halogen by trifluoromethyl in benzenoid and heterocyclic aromatic systems, as well as in alkenyl and alkyl halogen compounds.The mechanism of this interesting copper-assisted process has been explored and an intermediate of the form - is proposed.Introduction of higher perfluoroalkyl groups from their respective sodium perfluoroalkane carboxylates has been demonstrated and the machanistic features are compared with those of the trifluoromethylation process.
- Carr, Gillian E.,Chambers, Richard D.,Holmes, Thomas F.,Parker, David G.
-
p. 921 - 926
(2007/10/02)
-
- The Decomposition of t-Butyl Heptafluoroperoxybutyrate in Aromatic and Aliphatic Solvents
-
Kinetical studies and products analyses of the thermal decomposition of t-butyl heptafluoroperoxybutyrate (TBH) in benzene, octane, nitrobenzene, pyridine, and methoxybenzene have been carried out.In benzene and octane, the decoposition appears to be entirely a radical process.In nitrobenzene and pyridine, the reactions are found to give ionic decomposition proudcts exclusively.On the other hand, the decomposition of TBH in methoxybenzene is characteristic of mixed ionic and radical cleavages.
- Sawada, Hideo,Hagii, Hidehiko,Aoshima, Kazuyoshi,Yoshida, Masato,Kobayashi, Michio
-
p. 3448 - 3452
(2007/10/02)
-
- DIRECT PERFLUOROALKYLATION OF FUNCTIONALIZED BENZENES WITH PERFLUOROALKYL HALIDES AND COPPER BRONZE
-
Perfluoroalkyl halides were found to react with functionalized benzenes in the presence of copper bronze to give the corresponding perfluoroalkylated products directly in moderate to good yields.The reaction may involve' active species' other than perfluoroalkylcopper species.Synthetic utility and possible mechanisms of the present one-step reaction are discussed.
- Fuchikami, Takamasa,Ojima, Iwao
-
p. 541 - 556
(2007/10/02)
-
