434-64-0Relevant articles and documents
On the mechanism of the reaction of CF3 radicals with C6F5Cl in the temperature range 318-473 K
Nieto,Lane,Oexler
, p. 868 - 871 (1997)
The gas-phase reaction of CF3 radicals, generated by photolysis of perfluoroacetic anhydride, with C6F5Cl was studied in the temperature range 318-473 K and total pressures between 23 and 41 Torr. CF3 radicals react with C6F5Cl according to the following mechanism: CF3 + C6F5Cl ?kadd CF3C6F5Cl (1), (-1) CF3 + CF3C6F5Cl → CF3Cl + C6F5CF3 (2) 2CF3 →kc C2F6 (3) It was found that the addition reaction becomes reversible above 390 K. The addition rate parameters can be summarized in the following equation: log [(kadd/kc1/2)mol-1/2cm 3/2s-1/2] = (4.46±0.10)-(22.48±0.70)/θ where θ = 2.303 RTkJ mol-1 and kc is the recombination constant of CF3 radicals. A correlation between log(kadd/kc1/2) and the ionization potentials for 15 aromatic compounds was found. VCH Verlagsgesellschaft mbH, 1997.
(Perfluoroalkyl)polyfluoroarenes by copper-promoted cross-coupling of perfluoroalkyl halides and polyfluoroarenes
Weigert, F. J.
, p. 1 - 9 (1993)
Group 11 and 12 metals act as halogen acceptors to promote a selective cross-coupling between perfluoroalkyl halides and polyfluoroarenes to give (perfluoroalkyl)polyfluoroarenes.This reaction is a non-catalytic, fluorine analog of Friedel-Crafts alkylation in hydrocarbon chemistry.
A Key Intermediate in Copper-Mediated Arene Trifluoromethylation, [nBu4N][Cu(Ar)(CF3)3]: Synthesis, Characterization, and C(sp2)?CF3 Reductive Elimination
Lu, Zehai,Liu, He,Liu, Shihan,Leng, Xuebing,Lan, Yu,Shen, Qilong
supporting information, p. 8510 - 8514 (2019/05/22)
The synthesis, characterization, and C(sp2)?CF3 reductive elimination of stable aryl[tris(trifluoromethyl)]cuprate(III) complexes [nBu4N][Cu(Ar)(CF3)3] are described. Mechanistic investigations, including kinetic studies, studies of the effect of temperature, solvent, and the para substituent of the aryl group, as well as DFT calculations, suggest that the C(sp2)?CF3 reductive elimination proceeds through a concerted carbon–carbon bond-forming pathway.
Me3SiCF3/AgF/Cu - A new reagents combination for selective trifluoromethylation of various organic halides by trifluoromethylcopper, CuCF3
Kremlev, Mikhail M.,Mushta, Aleksej I.,Tyrra, Wieland,Yagupolskii, Yurii L.,Naumann, Dieter,M?ller, Angela
experimental part, p. 67 - 71 (2012/03/10)
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.
Copper-catalyzed direct C-H oxidative trifluoromethylation of heteroarenes
Chu, Lingling,Qing, Feng-Ling
supporting information; experimental part, p. 1298 - 1304 (2012/02/16)
This article describes the copper-catalyzed oxidative trifluoromethylation of heteroarenes and highly electron-deficient arenes with CF 3SiMe3 through direct C-H activation. In the presence of catalyst Cu(OAc)2, ligand 1,10-phenanthroline and cobases tert-BuONa/NaOAc, oxidative trifluoromethylation of 1,3,4-oxadiazoles with CF3SiMe3 proceeded smoothly using either air or di-tert-butyl peroxide as an oxidant to give the corresponding trifluoromethylated 1,3,4-oxadiazoles in high yields. Di-tert-butyl peroxide was chosen as the suitable oxidant for oxidative trifluoromethylation of 1,3-azoles and perfluoroarenes. Cu(OH)2 and Ag2CO3 were the best catalyst and oxidant for direct oxidative trifluoromethyaltion of indoles. The optimum reaction conditions enable oxidative trifluoromethylation of a range of heteroarenes that bear numerous functional groups. The prepared trifluoromethylated heteroarenes are of importance in the areas of pharmaceuticals and agrochemicals. The preliminary mechanistic studies of these oxidative trifluoromethylations are also reported.
Oxygen replacement by fluorine in carbonyl derivatives of perfluoroaromatic compounds and isomerization of perfluoroindan-1,3-dione to perfluoro-3-methylenephthalide under the action of HF/SbF5
Zonov, Yaroslav V.,Karpov, Victor M.,Platonov, Vyacheslav E.,Rybalova, Tatjana V.,Gatilov, Yuri V.
, p. 1574 - 1583 (2008/09/18)
When acted upon by HF/SbF5 at 95 °C, carbonyl groups of perfluorinated acetophenone (10), 3,4-dihydronaphthalen-1(2H)-one (8), 2,3-dihydronaphthalene-1,4-dione (9), benzocyclobutenone (6), benzocyclobutenedione (7) and indan-1-one (1) are converted into difluoromethylene groups to give the corresponding perfluoroaromatic products. Perfluoroindan-2-one (5), under the same conditions, is transformed to bis(perfluoroindan-2-yl) ether (21). On heating with HF/SbF5, perfluoroindan-1,3-dione (2) isomerizes into perfluoro-3-methylenephthalide (4) at 95 °C, and gives 4,5,6,7-tetrafluoro-3-trifluoromethyl-phthalide (14) at 130 °C. Compound 4 in the absence of a solvent dimerizes giving perfluorodispiro[phthalide-3,1′-cyclobutane-2′,3″-phthalide] (18), and when heated with SbF5 at 130 °C, it is converted into perfluoro-3-methylphthalide (3). When acted upon by HF/SbF5 at 95 °C, perfluorinated benzoic acid (12) and phthalic anhydride (13) give the corresponding products with trifluoromethyl groups.
Skeletal transformations and fluorination of perfluoroalkylbenzenes in reactions with antimony pentafluoride
Karpov,Mezhenkova,Platonov
, p. 1176 - 1181 (2007/10/03)
Reaction of octafluorotoluene and perfluoro-m-xylene with tetrafluoroethylene in the presence of SbF5 yielded perfluorinated propyl-and 1,3-dipropylbenzene, and propyltoluene. The perfluoropropyl group of these compounds under the action of SbF5 at 200°C is transformed into perfluoroisopropyl or trifluoromethyl group. Polyfluoroalkylbenzenes in SbF5 medium undergo fluorinationb to afford perfluoro1-alkylcyclohexenes.
Chlorine Abstraction Reaction from Chloroprentafluorobenzene by the CF3 Radical
Nieto,Herrera,Lane,Oexler
, p. 821 - 825 (2007/10/03)
The temperature dependence of the rate constant for the gas phase abstraction reaction of chlorine by CFj from chloropentafluorobenzene was determined in the temperature range 573-653 K by the competitive method using the recombination of CF3 radicals as reference reaction. Taking a value of 1.53-1013 cm3 mor1 s-1 for the recombination rate constant, kc, = (6.76± 1.26) 1012 exp [-(6339±103) K/7] cm3 mor1 s-1. The Arrhcnius parameters were calculated by the Bond Strength-Bond Length method (BSBL) and good agreement was obtained with the experimental values. WILEY-VCH Verlag GmbH, 1998.
Reactivity of Negative Ions with Trifluoromethyl Halides
Morris, Robert A.,Viggiano, A. A.,Miller, Thomas M.,Seeley, John V.,Arnold, Susan T.,et al.
, p. 10641 - 10645 (2007/10/03)
The kinetics of the reactions of selected anions (A(-)) with the trifluoromethyl halides CF3X (X = F, Cl, Br, I) in the gas phase were measured at 300 K.Reaction rate constants and product branching fractions were determined using a selected ion flow tube (SIFT) instrument.The chosen anions were C5F5N(-), o-, m-, and p-CF3C6H4CN(-), C6F5Br(-), C6F5Cl(-), C6F5CF3(-), C6F5COCH3(-), Fe(-), FeCO(-), SF6(-), SO(-), SO2(-), NO(-), NO2(-), and NO3(-).The reactivity of these systems varies from unreactive to collisional, and a variety of reaction types was found.The results of our present and previous measurements on A(-) + CF3X reactions show that, in cases where nondissociative electron transfer (NDET) is energetically allowed, the total reactivity tends to be high, approaching collisional.This suggests that reactivity in these cases is initiated and controlled by electron transfer from the anion.In addition, association reactions tend to be preempted when NDET is energetically allowed.A few exceptions to these tendencies were found and are discussed.
Fluorination of tetrafluorobenzenes C6HF4R with XeF2
Bardin,Shchegoleva,Frohn
, p. 153 - 159 (2007/10/03)
Replacement of hydrogen by fluorine and addition of fluorine atoms to the aromatic ring were found in the reaction of XeF2 with 1-R-2,3,4,5-tetrafluorobenzene (R = H, F, Br, NO2) or 1-R-2,3,4,6-tetrafluorobenzene (R = H, CF3) in HF or CH2Cl2-BF3·OEt2. Only fluorine addition took place in the case of 1-R-2,3,5,6-tetrafluorobenzenes (R = H, Br, CF3) or 1-Br-2,3,4,6-tetrafluorobenzene. The role of cation radicals as reactive intermediates is discusseed.
