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1.
Telomerizations by redox catalysis of vinyl and allyl acetates with carbon tetrachloride, 1,1,1 trichlorotrifluoroethane and CCl3(CF2CFCl)nCl were studied. Chemical transformation of these telomers by various ways leads to corresponding alcohols: RCCl2CH2CH2OH and RCCl2CH2CHClCH2OH with R = Cl, CF3, Cl(CFClCF2)n.  相似文献   

2.
In order to synthesize poly-(fluorinated alkanesulfonamides) a series of model experiments were carried out: (1) reactions of fluorinated alkanesulfonyl fluorides with amines, (2) reactions of fluorinated alkanesulfonyl chloride with amines and (3) reactions of sodium salts of fluorinated alkanesulfonamides with alkyl iodides of fluorinated alkanesulfonic acid esters. Seventeen new fluorinated alkanesulfonamides were prepared in good yields, namely: RFO(CF2)2SO2NR1R2 (1a-h), R1R2NSO2RFSO2NR1R2 (2a-h) and [Cl (CF2)4O(CF2)2SO2NH(CH2)3]2 (3). Reaction of RFSO2NH2 with equivalent amount of NaOCH3 and methyl iodide was shown to give both the N-mono- and N,N-di-substituted amides. Consequently the N-monosubstituted alkanesulfonamides were chosen as monomers for syntheses of the poly-(fluorinated alkanesulfonamides) and two new polymers were synthesized. The effect of the condition of the polycondensation on M?n of the polymers were discussed and elemental composition, 19F NMR, IR, M?n, Tg, tensile strength, thermal and chemical stabilities of the polymers were measured. Several new perfluoroalkanesulfonyl chlorides CISO2RFSO2Cl (4a-c) and fluorinated alkanesulfonic acid esters (6a-d) were synthesized. However, reaction of CFCl2CF2O(CF2)2SO2F with AlCl3 was found to give Cl3CCF2O(CF2)2SO2F (5) instead of the expected sulfonyl chloride.  相似文献   

3.
In this paper we report syntheses of F-alkyl compounds such as RFC2H4S(O)nCH2Z (with n=0,2 and Z=H,Ø(C6H5),COØ,COOEt,COCH3,CN). Using the carbanionic reactivity of these compounds, we would like to use them as precursors of surfactants, grafting hydrophilic functions on the carbons α or α′ to the sulfur atom. The compounds were not very reactive. Alkylation or acylation on this site could only be obtained with a ‘pseudo malonic’ CH2 (RFC2H4SO2CH2Z with Z=COØ, COOEt,COCH3,CN). Only methyl iodide and acetyl chloride led to positive results.  相似文献   

4.
A series of previously unknown asymmetrical fluorinated bis(aryl)bromonium, alkenyl(aryl)bromonium, and alkynyl(aryl)bromonium salts was prepared by reactions of C6F5BrF2 or 4-CF3C6H4BrF2 with aryl group transfer reagents Ar′SiF3 (Ar′ = C6F5, 4-FC6H4, C6H5) or perfluoroorganyl group transfer reagents RF′BF2 (RF = C6F5, trans-CF3CFCF, C3F7C≡C) preferentially in weakly coordinating solvents (CCl3F, CCl2FCClF2, CH2Cl2, CF3CH2CHF2 (PFP), CF3CH2CF2CH3 (PFB)). The presence of the base MeCN and the influence of the adducts RF′BF2·NCMe (RF = C6F5, CF3C≡C) on reactions aside to bromonium salt formation are discussed. Reactions of C6F5BrF2 with AlkF′BF2 in PFP gave mainly C6F5Br and AlkF′F (AlkF′ = C6F13, C6F13CH2CH2), presumably, deriving from the unstable salts [C6F5(AlkF′)Br]Y (Y = [AlkF′BF3]). Prototypical reactivities of selected bromonium salts were investigated with the nucleophile I-and the electrophile H+. [4-CF3C6H4(C6F5)Br][BF4] showed the conversion into 4-CF3C6H4Br and C6F5I when reacted with [Bu4N]I in MeCN. Perfluoroalkynylbromonium salts [CnF2n+1C≡C(RF)Br][BF4] slowly added HF when dissolved in aHF and formed [Z-CnF2n+1CFCH(RF)Br][BF4].  相似文献   

5.
Ten fluoromonomers of structure (RFO)2P(O)OCH2CH2OC(O)CRCH2 were made in 30-64% yield by treating the chloridates (RFO)2P(O)Cl with HOCH2CH2OC(O)CRCH2 in chloroform in the presence of triethylamine [RF=CF3CH2, C2F5CH2, C3F7CH2, C4F9CH2, C4F9CH2CH2 or C6F13CH2CH2; R  H or Me]. The chloromonomer (CCl3CH2O)2P(O)OCH2CH2OC(O)CHCH2 was obtained analogously in 29% yield. Polymerisation of the acrylate monomers, but not the methacrylate monomers, could be effected using α-azoisobutyronitrile as a radical initiator. Acrylic polymers having CF3CH2O, CCl3CH2O and C6F13CH2CH2O side-chains were obtained as translucent rubbers. Specimens of cotton fabric were treated with solutions of the polymers, and average water and oil repellency ratings measured. Fabric coated with the polymer with the C6F13CH2CH2O side-chain afforded protection from penetration of the test liquids. Treated fabrics were subjected to the limiting oxygen index (LOI) test according to BS EN ISO 4589-2 (1999): this test determines the point at which a material just burns in a volumetric flow of oxygen and nitrogen. The treated fabrics were more fire-resistant (LOI 22-29%) than the untreated fabric (LOI 18%). Fabric coated with the CCl3CH2O-based polymer can be considered fire-retardant (LOI 29%). The fluoromonomers were tested for anti-acetylcholinesterase activity and were found to be poor enzyme inhibitors; they are predicted to possess low acute toxicity.  相似文献   

6.
The reactivity of bis(fluoroalkyl) phosphorochloridates to nucleophiles is summarised. Previous data and the results described here indicate that reactivities decrease in the order: amines>alcohols>thiols. The synthesis of CF3CH2OP(O)(SEt)2 in 30% yield was accomplished by treating CF3CH2OP(O)Cl2 with two molar equivalents of EtSH and Et3N in ether. The chloridates (CF3CH2O)2P(O)Cl and (C2F5CH2O)2P(O)Cl did not react with MeSH in ether at −78 °C or when heated with Pb(SMe)2 in benzene. Ethanethiol and propanethiol reacted with fluorinated chloridates in the presence of triethylamine to give thiolates (RFO)2P(O)SR in 13-41% yield where RF was CF3CH2, C2F5CH2, C3F7CH2 or (CF3)2CH and R was Et or n-Pr. Similarly, reaction of phosphorobromidates (RFCH2O)2P(O)Br, made by brominating the corresponding bis(fluoroalkyl) H-phosphonates, with benzenethiol gave derivatives (RFCH2O)2P(O)SPh in 43 and 46% yield where RF was CF3 and C2F5, respectively. Treatment of the chloridothiolate Cl(EtO)P(O)SMe, prepared in two steps from triethyl phosphite, with fluoroalcohols and triethylamine in ether gave species RFO(EtO)P(O)SMe in 62-74% yield where RF was CF3CH2, C2F5CH2, C3F7CH2 or (CF3)2CH. The reactions of bis(trifluoroethyl) phosphorochloridate with 2-mercaptoethanol, 3-mercaptopropanol and ethane-1,2-dithiol gave several unexpected products whose structures were tentatively assigned.  相似文献   

7.
Metallation of thiols RFC2H4SH followed by alkylation with iodides R′FC2H4I leads either to symmetrical or to unsymmetrical sulphides RFC2H4SC2H4R′F (with RF=R′F or RF ≠ R′F). All compounds obtained are good solvents of gases (particularly O2, CO, CO2, N2).This property allows their application as biological carriers of dissolved gases.  相似文献   

8.
The reaction of mercuric salts HgY2 or organic mercuric compounds RHHgX with long chain perfluorinated Grignard reagents RFMgBr leads to a series of new perfluoroalkyl mercury derivatives with the general formula RFHgZ (RF=C4F9, C6F13, C8F17 ; Z=RF,RH,Y with Y = I,Br,Cl, NO3,OCOCH3,OCOCF3).The synthesis of these organomercuric compounds is described, and their spectroscopic properties are reported.  相似文献   

9.
Perfluorinated sulphonic esters RFSO3R'F and fluorosulphates FSO3R'F, are easily obtained by anodic oxidation of iodoperfluoroalkanes R'FI in perfluoroalkane sulphonic acids RFSO3H (RF  CF3, C2F5, C4F9) and fluorosulphuric acid. With di-iodo compound I(CF2)4I, the mono and the diester can be selectively obtained. The alkaline hydrolysis of these esters produces perfluorinated carboxylic compounds. Polyfluorinated iodide R'FCH2CH2I are also oxidized in similar conditions. The mechanism of the electrolytic reaction is discussed.  相似文献   

10.
Fluorinated acrylates and methacrylates radiolyzed at 77 K polymerize upon heating in the range from the glass-transition to the melting temperature. In the case of acrylates, the temperature range of postradiation polymerization increases by more than 100 K with the increasing chain length of the perfluorinated substituent from C2F4 to C8F17. The introduction of perfluorinated substituents into methacrylate molecules makes it possible to obtain them in the glassy state and to carry out low-temperature postradiation polymerization, in contrast to their hydrocarbon analogues. The termination rate constant of the polymerization of fluorinated methacrylates has a lower value as compared to conventional methacrylates. The formation of crosslinked structures is suppressed during the copolymerization of fluorinated acrylates with methacrylates. The ESR spectra of growing polymer radicals of fluorinated acrylic ∼CH2C·H(COOCH2C6F13)∼ and methacrylic CH2C·(CH3)(COOCH2C2F4H)∼ monomers have been identified.  相似文献   

11.
The nascent vibrational energy distributions of the HF? formed in the reactions of a series of partially fluorinated alkanes (RFH; RF = CH2F, CHF2, CF3, C2F5, C3F7, and C7F15) with electronically excited oxygen atoms O(21D2) have been determined by measuring the appearance times of stimulated emissions from various vibration–rotation transitions in a grating-tuned optical cavity. The vibrational energy contents of the HF formed in these reactions were found to be considerably greater than statistically expected. These reactions are believed to occur via vibrationally excited short-lived α;-fluorinated alcohols (RFOH?), formed by insertion of the O(21D2) atoms into C? H bonds. The observation of nonstatistical energy partitioning in the above reactions is in clear contrast to the result obtained from the O(21D2) + CF3CH3 reaction that produces the β-fluorinated alcohol CF3CH2OH, from which the HF product carries a near statistical vibrational energy distribution. A mechanism for HF? formation in these very exothermic reactions is presented.  相似文献   

12.
Pseudo first‐order rate constants of the reaction of diethyl(ethyl cyanoacetato)aluminum [(C2H5)2Al(NCCHCOOC2H5)] with 17 fluorinated acrylates and methacrylates and five hydrocarbon analogs for references were investigated to examine the initiation reactivities of the anionic polymerization of fluorinated vinyl monomers to afford the reactivity order: CH2?C(CF3)COOC2H5 > CH2?C(CF3)COOCH(CH3)2 > CH2?CHCOOCH2C6F5 > CH2?C(CF3)COOC(CH3)3 > CH2?C(CF3)COOCH2C6F5 > CH2?C(CF3)COOCH(CF3)2 ≥ CH2?CHCOOCH3 > CH2?CHCOOCH2C6H5 ≥ CH2?C(CF3)COOCH2CF3 > CH2?C(CH3)COOCH2C6F5 > CH2?CHCOOCH2CF3 > CH2?CHCOOCH2C2F5 > CH2?CHCOOCH(CF3)2 > CH2?C(CH3)COOCH3 > CH2?C(CH3)COOCH2C6H5 ≥ CH2?C(CH3)COOCH2CH2C8F17 > CH2?C(CH3)COOCH(CH3)2 > CH2?C(CH3)COOCH2C2F5 ≥ CH2?C(CH3)COOCH2CF3. No rate constants for CH2?C(CH3)COOCH(CF3)2, CH2?CFCOOC(CH3)3, and CH2?CFCOOCH2C2F5 were obtained because of too fast polymerization. The incorporation of a trifluoromethyl group into the vinyl group enhanced the reactivity toward the delocalized carbanion. The reactivity of other fluorinated acrylates and methacrylates was concluded to approximately be controlled by the fluorine contents and the bulkiness of substituents of monomers. The reactivity was generally decreased by increasing fluorine contents of fluoroalkyl substituents in ester groups. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7011–7021, 2008  相似文献   

13.
The perfluoroethyl amines C2F5N(CF3)2, C2F5N(CF3)CHF2, and C2F5N(CHF2)2 have been isolated from the electrofluorination of N(CH3)3 as well as C2H5N(CH3)2. Evidence is presented that, in the former case, the C2F5 compounds are formed by ·CF3 attack on partly fluorinated trimethylamines NC3F9?nHn, n = 1 to 3. The compounds have been characterized by analytical, nmr and vibrational spectroscopic methods.  相似文献   

14.
Fluoroalkylsulfonyl chlorides, RfSO2Cl, in which Rf=CF3, C4F9, CF2H, CH2F, and CH2CF3, are used as a source of fluorinated radicals to add fluoroalkyl groups to electron‐deficient, unsaturated carbonyl compounds. Photochemical conditions, using Cu mediation, are used to produce the respective α‐chloro‐β‐fluoroalkylcarbonyl products in excellent yields through an atom transfer radical addition (ATRA) process. Facile nucleophilic replacement of the α‐chloro substituent is shown to lead to further diverse functionalization of the products.  相似文献   

15.
Five acrylic esters having different fluorine contents and distributions in their side-groups (i.e., CH2=CHC(O)OR, where R = ? C(CH3)2C6F4H, ? C(CH3)2C6F5, ? C(CF3)2C6F5, ? C(CF3)2C6H5, and ? C(CH3)2C6H5) have been prepared from the reactions of the lithium salts of their corresponding alcohols with acryloyl chloride. These monomers are polymerized under identical conditions by the radical initiator AIBN and five polyacrylates were prepared having the structure of ? [ ? CH2CHC(O)OR? ]n? . These addition polymers were compared and fully characterized by GPC, VPO, DSC, TGA, NMR, IR, and UV-visible spectroscopies, and they showed potential for practical applications. Significant differences in their thermal stabilities were found with respect to fluorine contents and distributions in these polyacrylates, and the highest stability arises from CF3 substitutions in the side-chains of the polymers. © 1994 John Wiley & Sons, Inc.  相似文献   

16.
Summary By means of cryogenic sampling and subsequent gas-chromatographic analysis vertical profiles of CCl4, CCl3F, CCl2F2, CClF3, CF4, C2Cl3F3, C2Cl2F4, C2ClF5, C2F6, CH3Cl and CH3CCl3 were derived for stratospheric heights up to 35 km. Vertical profiles of halocarbons computed by means of one-dimensional and two-dimensional models fall off less rapidly in the stratosphere than the measured profiles, this systematic discrepancy being due to deficiencies in the radiation and transport schemes of present models. It is shown that measured profiles of fully halogenated hydrocarbons provide a tool for systematically studying these deficiencies and thus improving the models. Sources and sinks of halocarbons are discussed, and an assessment of past and future sources of organically bound chlorine in the atmosphere is made.
Die vertikale Verteilung halogenierter Kohlenwasserstoffe in der stratosphäre
Zusammenfassung Die vertikalen Profile von CCl4, CCl3F, CCl2F2, CClF3, CF4, C2Cl3F3, C2Cl2F4, C2ClF5, C2F6, CH3Cl und CH3CCl3 wurden für stratosphärische Höhen bis zu 35 km mit Hilfe kryogener Probenahme und anschließender gas-chromatographischer Analyse bestimmt. Die mit Hilfe von ein- und zweidimensionalen Modellen berechneten Profile fallen in der Stratosphäre weniger schnell ab als die gemessenen. Dieser systematische Unterschied ist auf Mängel in den Strahlungs- und Transportmechanismen der gegenwärtigen Modelle zurückzuführen. Es wird gezeigt, daß die gemessenen Profile der vollhalogenisierten Kohlenwasserstoffe dazu dienen können, diese Mängel zu untersuchen und die Modelle zu verbessern. Ursprung und Verbleib der halogenierten Kohlenwasserstoffe werden beschrieben und vergangene und zukünftige Quellen organisch gebundenen Chlors in der Atmosphäre diskutiert.
  相似文献   

17.
Reaction of phosphorus trichloride with tert-butanol and fluoroalcohols gave bis(fluoroalkyl) phosphites (RFO)2P(O)H in 42-89% yield, where RF=HCF2CH2, H(CF2)2CH2, H(CF2)4CH2, CF3CH2, C2F5CH2, C3F7CH2, (CF3)2CH, (FCH2)2CH, CF3(CH3)2C, (CF3)2CH3C, CF3CH2CH2, C4F9CH2CH2 and C6F13CH2CH2. Treatment of these with chlorine in dichloromethane gave the bis(fluoroalkyl) phosphorochloridates (RFO)2P(O)Cl in 49-96% yield. The chloridate (CF3CH2O)2P(O)Cl was isolated in much lower yield from the interaction of thionyl chloride with bis(trifluoroethyl) phosphite. Heating the latter in dichloromethane with potassium fluoride and a catalytic amount of trifluoroacetic acid gave the corresponding fluoridate (CF3CH2O)2P(O)F in 84% yield. Treatment of bis(trifluoroethyl) phosphite with bromine or iodine gave the bromidate (CF3CH2O)2P(O)Br and iodidate (CF3CH2O)2P(O)I in 51 and 46% yield, respectively. The iodidate is the first dialkyl phosphoroiodidate to have been isolated and characterised properly—its discovery lags behind the first isolation of a dialkyl phosphorochloridate by over 130 years. The fluoroalkyl phosphoryl compounds are generally more stable than known unfluorinated counterparts.  相似文献   

18.
Dimethyl phosphorochloridate reacted with RFCH2NH2 in ether in the presence of Et3N to afford (MeO)2P(O)NHCH2RF, where RF = CF3 and C2F5, in 39 and 47% yield, respectively. Similar reactions with di-n-propyl and diisopropyl phosphorochloridates could be effected only with H2NCH2CF3 when 4-dimethylaminopyridine catalyst was added and (n-PrO)2P(O)NHCH2CF3 and (i-PrO)2P(O)NHCH2CF3 were isolated in 49 and 25% yield, respectively. Treatment of POCl3 with one molar equivalent each of H2NCH2CF3 and Et3N permitted the synthesis of Cl2P(O)NHCH2CF3 in 43% yield. Bis(fluoroalkyl) phosphorochloridates (RFO)2P(O)Cl, where RF = C2F5CH2, C3F7CH2 and (CF3)2CH, reacted with 2,2,2-trifluoroethylamine and 2,2,3,3,3-pentafluoropropylamine to furnish phosphoramidates (RFO)2P(O)NHCH2R, where R = CF3 or C2F5, in yields of 32-67%.  相似文献   

19.
This minireview updates non-exhaustive recent strategies of synthesis of original fluorosurfactants potentially non-bioaccumulable. Various strategies have been focused on (i) the preparation of CF3–X–(CH2)n–SO3Na (with X = O, C6H4O or N(CF3) and n = 8–12), (ii) the oligomerization of hexafluoropropylene oxide (HFPO) to further synthesize oligo(HFPO)–CF(CF3)CO–RH (where RH stands for an hydrophilic chain); (iii) the telomerization of vinylidene fluoride (VDF) with 1-iodopentafluoroethane or 1-iodononafluorobutane to produce CnF2n+1–(VDF)2–CH2CO2R (n = 2 or 4, R = H or NH4), (iv) the radical telomerization of 3,3,3-trifluoropropene (TFP) with isoperfluoropropyliodide or diethyl hydrogenophosphonate to prepare (CF3)2CF(TFP)x–RH or CF3–CH2–CH2–(TFP)y–P(O)(OH)2, and (v) the radical cotelomerization of VDF and TFP, or their controlled radical copolymerization in the presence of (CF3)2CFI or a fluorinated xanthate. In most cases, the surface tensions versus the surfactant concentrations have been assessed. These above strategies led to various highly fluorinated (but yet not perfluorinated) telomers whose chemical changes enabled to obtain original surfactants as novel alternatives to perfluorooctanoic acid (PFOA), ammonium perfluorooctanoate (APFO), or perfluorooctylsulfonic acid (PFOS) regarded as bioaccumulable, persistent, and toxic.  相似文献   

20.
A series of fluorinated β-diketones, RfC(O)CH2C(O)Rf (Rf=C6F13, Rf′=CF3; Rf=Rf′=C6F13, C7F15), have been prepared in reasonable yields by a two-step synthesis. On reaction with appropriate metal substrates, deprotonation and concurrent coordination of the perfluoroalkyl-derivatised β-diketonate ligands affords a range of fluorous metal complexes which have been characterised by elemental analysis, mass spectrometry, IR and NMR spectroscopies. The structures of [Cu(L-L)2(H2O)2] {L-L=CF3C(O)CHC(O)C6F13, C6F13C(O)CHC(O)C6F13} and [Cu(PPh3)2{C7F15C(O)CHC(O)C7F15}] have been determined by single-crystal X-ray diffraction.  相似文献   

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