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On the mechanism of the reaction of CF3 radicals with C6F5Cl in the temperature range 318-473 K
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.
Nieto,Lane,Oexler
p. 868 - 871
(1997)
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(Perfluoroalkyl)polyfluoroarenes by copper-promoted cross-coupling of perfluoroalkyl halides and polyfluoroarenes
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.
Weigert, F. J.
p. 1 - 9
(1993)
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A Key Intermediate in Copper-Mediated Arene Trifluoromethylation, [nBu4N][Cu(Ar)(CF3)3]: Synthesis, Characterization, and C(sp2)?CF3 Reductive Elimination
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.
Lu, Zehai,Liu, He,Liu, Shihan,Leng, Xuebing,Lan, Yu,Shen, Qilong
supporting information
p. 8510 - 8514
(2019/05/22)

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
experimental part
p. 67 - 71
(2012/03/10)

Copper-catalyzed direct C-H oxidative trifluoromethylation of heteroarenes
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.
Chu, Lingling,Qing, Feng-Ling
supporting information; experimental part
p. 1298 - 1304
(2012/02/16)

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
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.
Zonov, Yaroslav V.,Karpov, Victor M.,Platonov, Vyacheslav E.,Rybalova, Tatjana V.,Gatilov, Yuri V.
p. 1574 - 1583
(2008/09/18)

Skeletal transformations and fluorination of perfluoroalkylbenzenes in reactions with antimony pentafluoride
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.
Karpov,Mezhenkova,Platonov
p. 1176 - 1181
(2007/10/03)

Chlorine Abstraction Reaction from Chloroprentafluorobenzene by the CF3 Radical
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.
Nieto,Herrera,Lane,Oexler
p. 821 - 825
(2007/10/03)

Reactivity of Negative Ions with Trifluoromethyl Halides
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.
Morris, Robert A.,Viggiano, A. A.,Miller, Thomas M.,Seeley, John V.,Arnold, Susan T.,et al.
p. 10641 - 10645
(2007/10/03)

Fluorination of tetrafluorobenzenes C6HF4R with XeF2
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.
Bardin,Shchegoleva,Frohn
p. 153 - 159
(2007/10/03)

Regiospecific Syn Addition of (Polyfluoroaryl)copper Reagents to Fluorinated Acetylenes: Preparation and Subsequent Functionalization of Internal Vinylcopper Reagents
(Pentafluorophenyl)copper (C6F5Cu) can be prepared from a metathesis reaction between C6F5CdX (X = Br or C6F5) and CuY (Y = Cl or Br).The arylcopper reagent undergoes a stereo- and regiospecific syn addition to fluorinated alkynes, which results in the corresponding internal alkenylcopper intermediate.This vinylcopper reagent can be subsequently functionalized with a variety of electrophiles, including aryl, alkyl, allyl, and acyl halides, to afford tetrasubstituted fluoroalkenes.The para-substituted arylcopper analogs also successfully undergo the addition reaction.
MacNeil, Kathryn J.,Burton, Donald J.
p. 4411 - 4417
(2007/10/02)

Interaction of perfluorocarbons with carbon
Activated carbon is an effective stoichiometric fluorine acceptor which defluorinates perfluoroalkanes with the partial structure (Rf)2CFCF(Rf)2 to alkenes and perfluoroalkenes to dienes.Carbon catalyzes double-bond shifts, as well as cis/trans and ring-chain perfluoro-olefin isomerizations.Carbon effectively catalyzes TFE and HFP dimerizations.Less effecively, carbon catalyzes further oligomerization of TFE to give low yields of linear, internal olefins.Free radicals may be the key surface intermediates.
Weigert, F. J.
p. 67 - 72
(2007/10/02)

INFRARED LASER INDUCED DECOMPOSITION OF HEXAFLUOROBENZENE AND SOME MONOSUBSTITUTED DERIVATIVES. INTERMEDIACY OF THE PENTAFLUOROPHENYL RADICAL.
The infrared multiphoton laser induced reactions of hexafluorobenzene and related pentafluoro analogues (pentafluorobenzene, pentafluorochlorobenzene, pentafluorobromobenzene, and pentafluoroiodobenzene) have been investigated using a CO2 TEA laser.The study was carried out in order to define the decomposition products and to attempt to clarify their mode of formation.Thus, the products (relative yield, percent) of the irradiation of C6F6 (1027.3 cm-1; 0.73 J/cm2; 10 pulses; 25percent decomposition) were C2F4(64), C6F5CF3(28), C2F6(7), CF4(1) and that for C6F5H (949.4 cm-1; 0.80 J/cm2; 10 pulses; 25percent decomposition) was C2F4 and C6F5CF3.Increasing the number of pulses in the reaction with C6F6 decreased the amount of C2F4 and increased the amount of C6F5CF3 and C2F6 indicating secundary and tertiary reactions.Addition of halogen (X2, X = Cl, Br) to these reactions caused different products to be formed.Thus, the irradiation of a C6F6/Cl2 mixture (7.4/7 Torr; 1027.3 cm-1; 0.7 J/cm2; 35 pulses; 35percent reaction) afforded C6F5Cl(46); CF3Cl(24) and CF2Cl2(30).Irradiation of C6F5H/X2 mixtures afforded mainly C6F5X + HX.For example C6F5H/Br2 (10/40 Torr; 949.4 cm-1; 0.93 J/cm2; 10 pulses; 10percent reaction) gave C6F5Br and HBr exclusively.Irradiation of C6F5-X (X = Cl, Br, I) (977.2 cm-1; ca. 0.74 J/cm2; 200 pulses; 39-74percent reaction) gave C6F6 and a minor amount of decafluorobiphenyl , a radical combination product of the pentafluorophenyl radical (C6F5.).Increasing the fluence in these reactions gave similar products in most cases but in some instances increased the amount of C2F4 formed.The reactions and product distribution of the hydrogen substituted derivative (C6F5H) was examined in the presence of Br2 as a function of laser fluence and halogen concentration.It was found that the threshold for C6F5H decomposition was higher for the reaction involving Br2 (as compared with the reaction involving Cl2 or neat C6F5H).The presence of Br2 also decreased the amount of C6F5H that was decomposed, indicating a quenching process.The decomposition path with the lowest activation energie for these molecules is thought to be C6F5X -> C6F5. + X. and was accessible using a laser pulse with a fluence as low as 0.7 J/cm2.Using a higher laser fluence (ca. 1.2 J/cm2) di- and triatomic radicals were defined by spectroscopic identification of the and :CF2 species.These reactions are discussed in light of the formation of the C6F5. radical during a primary, laser induced, process.Subsequent decomposition to smaller fragments, combination with other radicals or scavenging by added reagents also takes place depending on the reaction conditions.
Watanabe, Akio,Koga, Yoshinori,Sugawara, Ko-ichi,Takeo, Harutoshi,Fukuda, Kenzo,Matsumura, Chi
p. 463 - 469
(2007/10/02)

Infrared Multiphoton Decomposition of Hexafluorobenzene Investigated by Diode Laser Kinetic Spectroscopy: Detection of CF and CF2
Infrared multiphoton decomposition of hexafluorobenzene (C6F6) was investigated by diode laser kinetic spectroscopy.Two transient species, CF and CF2, were detected, and the time evolution of their signals was observed.The signal of CF rose within 10 μs after a CO2 laser pulse and decreased with lifetime of about 200 μs, while that of CF2 rose slowly as CF decayed out.Final products observed by an FTIR spectrometer were mostly C2F4 and C6F5CF3.These experimental results suggested that CF was produced at the early stage of the reaction and that CF2 was produced by the reaction of CF with a certain fluorine-containing species and then decayedout through the dimerization and/or the reaction with C6F6.
Sugawara, Ko-ichi,Watenabe, Akio,Koga, Yoshinori,Takeo, Harutoshi,Fukuda, Kenzo,et al.
p. 3647 - 3649
(2007/10/02)

ON SOME NEW TRIFLUOROMETHYL IODINE(III) COMPOUNDS: REACTIONS OF CF3IF2 WITH BORON AND SILICON COMPOUNDS AND CF3ICl2 WITH SILVER SALTS
CF3IF2 undergoes fluorine exchange reactions with BX3 (X = Cl, Br, I, OCOCF3) to form the compounds CF3IX2.The reactions of CF3IF2 with (CF3)2BN(CH3)2, (CH3)3SiNCO and (CH3)3SiN(CH3)COCF3 yield the corresponding new trifluoromethyl iodine (III) nitrogen compounds.A preparative method for the synthesis of CF3ICl2 is found by reacting CF3IF2 with (CH3)3SiCl.CF3ICl2 reacts with AgX (X = OCOCF3, SCF3) to yield the corresponding CF3IX2 compounds and with (C6H5)4AsCl the novel ion (-) is detected.Products were identified by n.m.r. spectroscopy.
Tyrra, Wieland,Naumann, Dieter
p. 401 - 416
(2007/10/02)

FLUORINATIONS WITH COMPLEX METAL FLUORIDES. PART 9. FLUORINATIONS OF TOLUENE AND XYLENE DERIVATIVES BY MEANS OF CAESIUM TETRAFLUOROCOBALTATE(III)
Benzotrifluoride at 320 deg C afforded some m-fluorobenzotrifluoride and octafluorotoluene (III), together with perfluoromethylcyclohexane (I), and also traces of 2H-heptafluorotoluene and 1-trifluoromethylnonafluorocyclohex-1-ene.Toluene itself gave (difluoromethyl)benzene, fluoro- and difluoro-methylpentafluorobenzene, difluoromethylundecafluorocyclohexane and (I); also traces of di- and tri-fluoromethylnonafluorocyclohex-1-ene: no benzotrifluoride or (III) were detected. 1,3-Bis(trifluoromethyl)benzene at 420 deg C gave 4,5,6-trifluoro-1,3-bis(trifluoromethyl)benzene, decafluoro-1,3-dimethylbenzene, and perfluoro-1,3-dimethylcyclohexane.Para-xylene at 350 deg C afforded 1,4-bis(difluoromethyl)tetrafluorobenzene, 1-difluoromethyl-4-trifluoromethyltetrafluorobenzene, decafluoro-1,4-dimethylbenzene (XIX), and perfluoro-1,4-dimethylcyclohexane (XVIII).Defluorination occurred to a significant extent on passage of the saturated cyclic fluorocarbons (I) and (XVIII) over the fully spent fluorinating agent (presumably caesium trifluorocobaltate) at ca. 400 deg C; the fluorocarbon arenes, (III) and (XIX) respectively, were obtained.
Bailey, John,Plevey, Raymond G.,Tatlow, John Colin
p. 1 - 14
(2007/10/02)

Laser-Induced Reactions of Hexafluorobenzene and Selected Hydride Compounds
Infrared-laser-induced reactions between C6F6 and general hydrides R-H (R = H, D, CH3, HCC, H2C=CH, and Cl) were studied by irradiating C6F6 at 1027 cm-1 in C6F6/R-H mixtures.In general, two competitive pathways involving C-F bond cleavage in C6F6 were observed as follows: (1) C6F6 + R-H C6F5H + R-F and (2) C6F6 + R-H C6F5R + HF.C6F6 decomposition also took place to a minor extent depending on the mole fraction of C6F6 and gave rise to C2F4 and C2H2.From infrared and GC/MS analysis of the product mixtures after 20-200 pulses, C6F5H was observed in all reactions except that involving D2.When D2 was used C6F5D was the major product.C6F5H was the major product in the reactions involving H2 and C2H2.In the reaction with C2H4, C6F5H was the major product derived from C6F6 though C2H2 was the major product of the reaction.The large amount of C2H2 seems to be derived from an additional sensitized decomposition of C2H4.C6F5H was present in minor amounts in the reaction with CH4 and HCl.Besides C6F5H, other monosubstituted products derived from C6F6 were also formed, generally within 20-100 pulses.Thus, C6F5CH3, C6F5CH=CH2, C6F5CCH, and C6F5Cl were produced, respectively, in the reaction of C6F6 with CH4, C2H4, C2H2, and HCl.In the first and last cases these products were the major ones observed.The results are discussed mechanistically in terms of the initial formation of the C6F5. radical and synthetically in terms of the utility of obtaining selective-laser-induced reduction of C6F6.
Koga, Yoshinori,Chen, Ruth,Keehn, Philip M.
p. 306 - 311
(2007/10/02)

The Preparation and Characterization of Radical Cation Salts Derived from Perfluorobenzene, Perfluorotoluene, and Perfluoronaphthalene
The salts C6F6+AsF6- (yellow), C6F5CF3- (lime green), and C10F8+AsF6- (dark green) may be prepared by electron oxidation of the appropriate perfluoro aromatic molecule with O2+AsF6-.Other O2+ salts can be similarly employed as can the more strongly oxidizing transition-metal hexafluorides, but salts of the latter are more labile than their AsF- relatives.C6F6+AsF6- is a convenient electron oxidizer (C6F6AsF6+C10F8 -> C10F8AsF6+C6F6) since that which remains from the reaction decomposes at room temperature to volatile products (2C6F6AsF6 -> C6F6+1,4-C6F8+2AsF5).Magnetic susceptibilities for C6F6AsF6 and C10F8AsF6 approximate to Curie law behavior, and g values are close to free-electron values.X-ray diffraction data (single crystal) show C6F6AsF6 to be primitive rhombohedral with a0=6.60 (1) Angstroem, α=106.0 (1) deg, V=246.1 Angstreom3, Z=1, probable space group R3, and (powder data) C10F8AsF6 to be tetragonal with a0=8.27 (5) Angstroem, c0=18.57 (s) Angstroem, V=1270 Angstoem3, Z=4.Salts derived from the monocyclic perfluoro aromatics are thermally unstable but can be kept below -15 deg C.The perfluoronapthalene salts are indefinitely stable at room temperatures.All hydrolyze rapidly.The products of thermal decomposition of the hexafluoroarsenates of the monocyclic cation salts parallel the products of the attack by F-.The latter reaction products are in the molar ratios indicated by the following equations: 2C6F6+ 2F- -> C6F6+ 1,4-C6F8; 2C6F5CF3+ ->2F- -> C6F5CF3+1,3-C6F7CF3.The 1,3-C6F7CF3 isomerizes to a 1:1 mixture with 1,4-C6F7CF3 over several days in the presence of fluoro acids.Mechanisms for the formation of the dienes are discussed.
Richardson, T. J.,Tanzella, F. L.,Bartlett, Neil
p. 4937 - 4943
(2007/10/02)

REACTION OF POLYFLUORINATED DERIVATIVES OF BENZENE CONTAINING HYDROGEN ATOMS IN THE SIDE CHAIN WITH VANADIUM PENTAFLUORIDE
The treatment of C6F5R (R=CH3, CH2F, CHF2) compounds with vanadium pentafluoride at -25 to -30 deg C leads to a 1-R-heptafluoro-1,4-cyclohexadienes, 1-R-nonafluorocyclohexenes, and products form fluorination of the side chain.Fluorination of the anisole derivatives C6F5OCH3 and C6F5OCHF2 only takes place in the aromatic ring.
Avramenko, A. A.,Bardin, V. V.,Karelin, A. I.,Krasil'nikov, V. A.,Tushin, P. P.,et al.
p. 2318 - 2323
(2007/10/02)

REACTIONS OF POLYFLUOROAROMATIC COMPOUNDS WITH VANADIUM PENTAFLUORIDE
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Avramenko, A. A.,Bardin, V. V.,Furin, G. G.,Yakobson, G. G.,Krasilnikov, V. A.,et. al
p. 141
(2007/10/02)

AROMATIC FLUORINE DERIVATIVES. XCVIII. HEPTAFLUOROPHENYLACETIC ACID. PRODUCTION AND SOME PROPERTIES
A mixture of C6F5CHFCN and C6F5CF2CN is formed by the action of perchloryl fluoride on pentafluorophenylacetonirile in the presence of cesium fluoride.Hydrolysis of the second product gave the previously unknown heptafluorophenylacetic acid.This acid was also synthesized by the oxidation of perfluoroallylbenzene with potassium permanganate.The chloride, fluoride, amide, and methyl ester of heptafluorophenylacetic acid were obtained.
Bardin, V. V.,Furin, G. G.,Yakobson, G. G.
p. 514 - 519
(2007/10/02)

POLYFLUORO-COMPOUNDS BASED ON THE CYCLOHEPTANE RING SYSTEM. PART 5. OCTAFLUOROCYCLOHEPTA-1,3,5-TRIENE AND HEXAFLUOROTROPONE
Decafluorocyclohepta-1,3-diene underwent reductive addition-elimination with sodium borohydride to give mainly 1H-nonafluorocyclohepta-1,3-diene, together with minor products, the 1H,4H-octafluoro-analogue and, most significantly, 5H-nonafluorocyclohepta-1,3-diene.Decafluorocyclohepta-1,4-diene, together with some 6H-nonafluorocyclohepta-1,4-diene and a trace of the 5H-1,3-diene.These last two dienes were important products, having hydrogen on allylic carbons.They could be dehydrofluorinated, either by bubbling through molten potassium hydroxide or, better, with powdered alkali in an inert medium.Unless special precautions were taken, such reactions yielded hexafluorotropone.With care however the primary product, octafluorocyclohepta-1,3,5-triene, could be isolated, but it was hydrolysewd rapidly, even by water, to give the tropone.Isomerizations and pyrolytic dehydrofluorinations of the major reduction products were carried out, but none yielded the triene or the tropone.It seemed that the triene was probably formed but decomposed to give perfluoroarenes.An interesting defluorination pathway was also operating, to give pentafluorobenzene. 2H-Nonafluorocyclohepta-1,3-diene was an isomerization product.Hexafluorotropone reacted with sodium methoxide in methanol to give 3,6-dimethoxytetrafluorotropone.
Dodsworth, D. J.,Jenkins, C. M.,Stephens, R.,Tatlow, J. C.
p. 41 - 60
(2007/10/02)

CW CO2 LASER-INDUCED HALOGEN EXCHANGE REACTION BETWEEN HEXAFLUOROBENZENE AND BORON TRICHLORIDE
The halogen exchange reaction between hexafluorobenzene (HFB) and boron trichloride, BCl3 initiated by a continous-wave CO2 laser primarily affords chloropentafluorobenzene, C6F5Cl and dichlorofluoroborane, BCl2F.For the reaction initiation a number of rotational-vibrational lines of the vibrational 00deg1->10deg0 transition was used.With wavenumber radiation 977.21 cm-1 a faster V-V energy transfer between HFB and BCl3 molecules may occur.For this case the rate of the exchange reaction was observed to be by an order of magnitude higher compared to the reaction initiated by the laser radiation at 949.48 cm-1 and carried out under theidentical absorption conditions.
Engst, Pavel,Horak, Milan,Pola, Josef
p. 1314 - 1322
(2007/10/02)

Infrared Multiphoton Photochemistry of Hexafluorobenzene Studied by Time-Resolved Visible Luminescence Spectroscopy
C6F6 gas (0.15-3 torr) was irradiated with IR pulses at 1023 cm-1, where C6F6 absorbs strongly, and the time evolution of the visible/near-UV luminescence spectrum was examined.IR pulse fluence ranged mostly from 100 to 900 J cm-2, and square-pulse equivalent intensity from 2 to 18 GW cm-2.By use of a plasma shutter to truncate IR pulses after ca. 60 ns, luminescence evolving during irradiation could be clearly distinguished from that emitted subsequently.Kinetic measurements at 360 nm showed that luminescence begins shortly (10-20 ns) after the start of the IR pulse.After pulse truncation, the initial decay of luminescence comprises two first-order lifetimes, τA ca. 15 ns and τB = 575+/-75 ns.Time-resolved spectroscopy shows that the 575-ns emission agrees closely with a well-characterized emission, previously assigned to C3, seen in carbon furnaces and fuel-rich oxyacetylene flames.During the period 1.8-18.8 μs after the IR pulse, time-resolved spectra are dominated by broad-background emission, with sharp superposed intensity peaks assignable to C2 Swan bands.The broad-background emission during this period agrees with blackbody radiation spectra for temperatures decreasing from 3640 to 3440 K.The luminescence yield for the background emission varies at the square of the initial C6F6 pressure.Final reaction products are mostly C2F4(g) and a black solid ("fluorocoal") of approximate composition (C2F)n.It is suggested that the final products indicate not how the parent molecules decompose but how the fragments formed from them reassemble afterward as the gas temperature returns to ambient.
Dulgnan, Michael T.,Grunwald, Ernest,Speiser, Shammal
p. 4387 - 4394
(2007/10/02)

Formation of polyfluorinated aromatic compounds during the pyrolysis of chlorotrifluoroethylene
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Ivanova, S. M.,Boikov, Yu. A.,Barabanov, V. G.,V'yunov, K. A.,Ginak, A. I.
p. 2184 - 2185
(2007/10/02)

FLUOROCYCLOHEXANES. PART XVI. THE SIX H-TRIFLUOROMETHYLDECAFLUORO- AND TWO OF THE 2H,4H-TRIFLUOROMETHYLNONAFLUORO-CYCLOHEXANES
Fluorination of benzotrifluoride by cobaltic fluoride at 260-280 deg gave, besides the fluorocarbon, the six possible tridecafluoromethylcyclohexane isomers, and two 2H,4H-dodecafluorides.Of the C7HF13 compounds, only the cis-2H-, and the cis- and trans-4H-isomers could be isolated pure.The two 3H-isomers were made by pyrolysis of perfluoro(1-methyl-3-isopropylcyclohexane) in the presence of toluene.The trans-2H-isomer was made by further fluorination of one of the 2H,4H-dodecafluorides.Aqueous potash and the cis-2H-tridecafluoride gave 1-trifluoromethylnonafluorocyclohex-1-ene, which with stronger alkali hydrolysed to 1-carboxynonafluorocyclohex-1-ene.The cis- and trans- 2H and 4H-tridecafluorides were dehydrofluorinated by sodium fluoride at 320-380 deg (the cis-isomer of each pair reacted faster than the trans-: axial versus equatorial hydrogen) to give, respectively, the 1-trifluoromethylnonafluoro-ene and the 4-trifluoromethyl-isomer.The latter was isomerised to the former by sodium fluoride at 500-600 deg.The 1-CF3-ene gave hexafluoroglutaric acid on oxidation with alkaline potassium permanganate.
Alsop, Derek J.,Burdon, James,Carter, Paul A.,Patrick, Colin R.,Tatlow, John Colin
p. 305 - 316
(2007/10/02)

POLYFLUOROCYCLOALKENES. PART XVI . SOME ADDITION REACTIONS OF 1-TRIFLUOROMETHYLNONAFLUOROCYCLOHEX-1-ENE
Reactions with alcohols and base repleaced the vinylic fluorine of 1-trifluoromethylnonafluorocyclohex-1-ene (I) by methoxy and ethoxy groups.Fluorination with cobaltic fluoride gave, from the former, a number of saturated polyfluoro-ethers.Oxidation of the alkoxy-cycloalkenes gave hexafluoroglutaric acid.Cycloalkene I gave with ammonia an imino-enamine, which was hydrolysed by dilute acid to a keto-enamine.I was defluorinated by heated iron to octafluorotoluene.
Carter, Paul A.,Patrick, Colin R.,Tatlow, John Colin
p. 407 - 412
(2007/10/02)