354-55-2Relevant academic research and scientific papers
HALOGEN FLUOROSULFATE REACTIONS WITH FLUOROCARBONS
Shack, Carl J.,Christe, K. O.
, p. 63 - 74 (1980)
The scope of the reaction of simple fluorocarbon halides with chlorine fluorosulfate and mixtures of chlorine and bromine fluorosulfate to produce RfOSO2F compounds has been investigated.It is shown that in many cases even primary chlorine in -CF2Cl groups can be replaced by -OSO2F.Primary bromine or iodine in -CF2X are more readily replaced.The mechanism of this replacement reaction has been established by the isolation of the metastable iodine III intermediate RfI(OSO2F)2.Neither secondary chlorine nor bromine in -CFX- groups is affected.With the secondary iodide, i-C3F7I, the salt + - is formed.Furthermore, it has been found that ClOSO2F is capable of converting fluorocarbon acids or their derivatives into fluorocarbon halides.A combination of these two ClOSO2F reactions with the known conversion of RfCF2OSO2F to the corresponding fluorocarbon acid offers a novel, high yield chain shortening reaction for the otherwise unreactive fluorocarbon halides according to:
BROMINATION OF FLUOROALKENES PART 5.-KINETICS OF FORWARD AND REVERSE REACTIONS IN THE SYSTEM Br2+i-C3F7HHBr+i-C3F7Br
Evans, Brian S.,Weeks, Ian,Whittle, Eric
, p. 1471 - 1482 (1983)
The kinetics of the forward and reverse reactions in the gas-phase system have been studied.The slow steps for the forward and reverse reactions, respectively, are .The Arrhenius parameters obtained, for the range 421-534 deg C, are .The competitive brominations of mixtures of i-C3F7H+C2F5H and i-C3F7H+n-C3F7H have been studied over the ranges 249-430 and 220-402 deg C, respectively.Each system yielded Arrhenius parameters for reaction (2) which are in excellent agreement with those given above.The results lead to the following bond dissociation energies at 298 K: Attempts were made to measure D using competitive photobromination and photochlorination.However, (CF3)3C-H is so unreactive that only the approximate result D ca. 456 kJ mol-1 was obtained.The trends in C-H and C-Br bond dissociation energies are compared in alkanes, fluoroalkanes and the corresponding bromides.
Reactions of perfluorinated alkenyl-, alkynyl-, alkyltrifluoroborates, and selected hydrocarbon analogues with the halogenating agents Hal2 (Hal = F, Cl, Br), "brF" (BrF3-Br2 1:1), and ICl
Bardin, Vadim V.,Adonin, Nicolay Yu.,Frohn, Hermann-Josef
experimental part, p. 565 - 579 (2012/05/20)
Reactions of [Bu4N][RBF3] [R = CnF 2n+1CF=CF (cis, trans), CF2=CF, CF2=C(CF 3), trans-C4H9CF=CF, trans-C6H 5CF=CF, C4H9CH=CH (cis, trans), CF 3C≡C, and C4H9C≡C] with chlorine, bromine, BrF3 + Br2 (as equivalent of "BrF"), and ICl in solution (CH2Cl2, CHCl3, CF 3CH2CF2CH3) led to 1, 2-addition of halogen and/or replacement of boron by halogen (halodeboration). The reaction of [Bu4N][CF3C≡CBF3] with less than equimolar amounts of diluted fluorine (5 %) in 1, 1, 1, 3, 3-pentafluorobutane (PFB) showed only [Bu4N][CF3CF2CF 2BF3] as fluorine addition product besides extensive fluorodeboration. Suspensions of the insoluble K[CF2=CFBF 3] salt reacted with Cl2 and Br2 in CH 2Cl2 giving preferentially products of halogen addition across the C=C bond. In reactions with ICl iododeboration with formation of CF2=CFI occurred besides 1, 2-addition with formation of [CF 2I-CFClBF3]-. The halodeboration reaction of[Bu4N][trans-C4H9CF=CFBF3] with Br2, "BrF", and ICl, of K[trans-C6H 5CF=CFBF3] with Br2, and of [Bu 4N][trans-C4F9CF=CFBF3] with ICl proceeded stereospecifically. Copyright
GASEOUS DIELECTRICS WITH LOW GLOBAL WARMING POTENTIALS
-
, (2010/12/31)
A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about ?20° C. to about ?273° C.; non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL; and a dielectric strength greater than air.
Perfluoroalkyl hypobromites: Synthesis and reactivity with some fluoroalkenes
Anderson, John D.O.,DesMarteau, Darryl D.
, p. 147 - 152 (2007/10/03)
The first perfluoroalkyl hypobromites have been prepared by the reaction of bromine(I) fluorosulfate with perfluorinated tertiary alkoxides of general formula RfC(CF3)2ONa where Rf=CF3 or CF3CF2. These hypobromites are of lower thermal stability but they behave similarly to analogous hypochlorites and decompose rapidly above -20 °C to give CF3C(O) CF3 and either CF3Br or CF3CF2Br. New polyfluoroethers generated from the reaction of perfluoroalkyl hypobromites with fluoroalkenes have been characterized by 19F and 1H NMR spectroscopy, IR spectroscopy and MS.
Synthesis of functionalized polyfluoroalkyl hypochlorites and fluoroxy compounds and their reactions with some fluoroalkenes
Randolph, Bruce B.,DesMarteau, Darryl D.
, p. 129 - 150 (2007/10/02)
Several new polyfluoroalkyl hypochlorites and fluoroxy compounds containing Cl, H and Br in the alkyl group have been prepared and characterized by 19F NMR, 1H NMR and IR spectroscopies and by their reactions with fluoroalkenes to produce new polyfluoroethers.The novel compounds are prepared by the CsF-catalyzed addition of F2 or ClF to the C=O bond in CF3C(O)CF2Cl, ClCF2C(O)CF2Cl, and their derivatives HCF2C(O)CF3 and HCF2C(O)CF2Cl.Compounds containing an α-CF3 group exhibit enhanced thermal stability.New fluoroxy compounds and hypochlorites have also been prepared from the acid fluorides CF3-CFX-C(O)F (X = Cl, Br), which are obtained by the ring-opening reaction of hexafluoropropene oxide with (CH3)3SiCl, LiBr and (C2H5)3SiBr.These -OX compounds behave similarly to previously known materials with two α-F atoms, decomposing quickly at room temperature to COF2 and haloalkanes.
REACTION OF ORGANIC COMPOUNDS WITH SF4-HF-HALOGENATING SYSTEM VII. REACTIONS OF OLEFINS WITH THE SF4-HF-Cl2(Br2) SYSTEM
Kunshenko, B. V.,Mokhamed, Nagib Mukhtar,Omarov, V. O.,Muratov, N. N.,Yagupol'skii, L. M.
, p. 511 - 518 (2007/10/02)
Under the influence of the SF4-HF-Cl2(Br2) system halogen-containing olefins undergo conjugate halogenofluorination.It was shown for the case of (Z)- and (E)- 1,2-dichloroethenes that these reactions take place anti-stereospecifically through the formation of the bromonium ions.The accumulation of chlorine atoms in the olefin molecule hinders electrophilic addition of stoichiometric equivalents of ClF and BrF at the double bond.The SF4-HF-Br2 system is an effective agent for substitutive fluorination of organic compounds containing bromine.Only the bromine atoms situated at the secondary carbon atom are substituted by fluorine.
Infrared Multiphoton Dissociation of Heptafluoropropane
Kato, Shuji,Makide, Yoshihiro,Tominaga, Takeshi,Takeuchi, Kazuo
, p. 4278 - 4284 (2007/10/02)
The dissociation yield and branching ratio in CO2-laser-induced multiphoton dissociation (MPD) of CF3CF2CHF2 were studied as a function of irradiation frequency (979.7, 1037.4, and 1081.1 cm-1) and laser fluence (focal fluence 2).Br2 was successfully employed to reveal the dissociation mechanisms by scavenging a number of primary and secondary dissociation fragments produced in the MPD.At low laser fluences the distributions of scavenged products were the same regardless of irradiation frequencies.The primary dissociation of CF3CF2CHF2 was found to proceed mainly via the higher activation energy channels (i.e., C-C ruptures: CF3CF2CHF2 -> C2F5 + CHF2, and CF3CF2CHF2 -> CF3 + C2HF4) rather than via HF elimination (CF3CF2CHF2 -> C3F6 + HF) in our experimental conditions.The observed branching ratio between the two C-C rupture channels (ca. 2:1) agreed with the results obtained by RRKM calculation.A remarkable difference in product distribution with respect to the irradiation frequency was observed at higher laser fluences.This indicates that the secondary photolysis of primarily produced radicals within the laser pulse occured significantly at higher fluences (i.e., C2F5 -> CF3 + CF2, CHF2 -> CF2 + H, CF3 -> CF2 + F, and C2HF4 -> CF2 + CHF2), depending strongly upon the irradiation frequencies.
Synthesis of Perfluoroalkyl Trifluoromethanesulfonates from Perfluoroalkyl Halides. Substitutive Electrophilic Dehalogenation with Chlorine(I) and Bromine(I) Trifluoromethanesulfonates
Katsuhara, Yutaka,DesMarteau, Darryl D.
, p. 2681 - 2686 (2007/10/02)
The reactions of chlorine(I) and bromine(I) trifluoromethanesulfonates with a variety of perfluoroalkyl halides are reported.The reactions form Br2, Cl2, or BrCl and the corresponding trifluoromethanesulfonate derivatives of the alkyls in good yields.Twelve new esters are reported and characterized.An SEi-type mechanism for the reactions is proposed with complete retention of configuration by the alkyl on substitution.
