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1.
Fluoralkylamines (CF3)3?nN(CHF2)n, n = 1 to 3, and analogous C2F5 derivatives exhibit a selective reactivity of the CHF2 group towards Lewis acids like BCl3, TiCl4 and BBr3, CHCl2 and CHBr2 groups being formed in nearly quantitative yield. Halogenated trialkylamines of the general formulae (CF3)3?nN(CHCl2)n, n = 1 to 3, and (CF3)3?nN(CHBr2)n, n = 1 and 2, were obtained for the first time and characterized by nmr, ir, Raman and mass spectra. The halogen exchange reaction proceeds via an intermediate immonium cation, but the chloro and bromoalkyl amines are non-ionic. Both (CF3)2NCHF2 and (CF3)2NCHCl2 undergo photochlorination to yield (CF3)2NCF2Cl and (CF3)2NCCl3.  相似文献   

2.
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   

3.
Multicage fullerene cycloadducts have been detected by MALDI mass spectrometry; they have been found as admixtures in the products of reactions of the trifluoromethylation of fullerene samples doped with metallic sodium, the reaction between fullerenes and a mixture of trifluoromethylfullerenes, and the synthesis of fulleroproline esters. As a result, over 75 new compounds of this type have been identified. The optimization of the synthesis procedures and chromatographic fractionation allowed us to extract five compounds in the pure form: (C60)2(CF2)2(CF3)8, (C60)2(CF2)2(CF3)3C2F5, (C60)2(CF2)2(CF3)5C2F5, (C60)2(CF2)2(CF3)2O, and C60CH2N(CH2C60)CCOOtBu. Chemical structures of two of them, proposed on the basis of post source decay mass spectra, have been further confirmed by NMR spectra.  相似文献   

4.
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   

5.
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   

6.
A detailed reaction mechanism is developed and used to model experimental data on the pyrolysis of CHF3 and the non-oxidative gas-phase reaction of CHF3 with CH4 in an alumina tube reactor at temperatures between 873 and 1173 K and at atmospheric pressure. It was found that CHF3 can be converted into C2F4 during pyrolysis and CH2CF2 via reaction with CH4. Other products generated include C3F6, CH2F2, C2H3F, C2HF3, C2H6, C2H2 and CHF2CHF2. The rate of CHF3 decomposition can be expressed as 5.2×1013 [s−1] e−295[kJ mol−1]/RT. During the pyrolysis of CHF3 and in the reaction of CHF3 with CH4, the initial steps in the reaction involve the decomposition of CHF3 and subsequent formation of CF2 difluorocarbene radical and HF. It is proposed that CH4 is activated by a series of chain reactions, initiated by H radicals. The NIST HFC and GRI-Mech mechanisms, with minor modifications, are able to obtain satisfactory agreement between modelling results and experimental data. With these modelling analyses, the reactions leading to the formation of major and minor products are fully elucidated.  相似文献   

7.
The reactions of sodium ethoxide in ethanol with various fluoroaromatics, C6F6?nHn, C6F5?nHnNO2, C6F5X (X = CF3, C6F5, COCH3, CH2Br), C6Cl6 and mH2C6Cl4 have been studied. Partial substitution of the aromatic halogen was observed. The new products have been characterized by elemental analysis, NMR (H?1 and F?19), infrared and mass spectroscopy.  相似文献   

8.
Thermal decarbonylation of the acyl compounds [Mn(CO)5(CORF)] (RF=CF3, CHF2, CH2CF3, CF2CH3) yielded the corresponding alkyl derivatives [Mn(CO)5(RF)], some of which have not been previously reported. The compounds were fully characterized by analytical and spectroscopic methods and by several single-crystal X-ray diffraction studies. The solution-phase IR characterization in the CO stretching region, with the assistance of DFT calculations, has allowed the assignment of several weak bands to vibrations of the [Mn(12CO)4(eq-13CO)(RF)] and [Mn(12CO)4(ax-13CO)(RF)] isotopomers and a ranking of the RF donor power in the order CF3<CHF2<CH2CF3≈CF2CH3. The homolytic Mn−RF bond cleavage in [Mn(CO)5(RF)] at various temperatures under saturation conditions with trapping of the generated RF radicals by excess tris(trimethylsilyl)silane yielded activation parameters ΔH and ΔS that are believed to represent close estimates of the homolytic bond dissociation thermodynamic parameters. These values are in close agreement with those calculated in a recent DFT study (J. Organomet. Chem. 2018 , 864, 12–18). The ability of these complexes to undergo homolytic Mn−RF bond cleavage was further demonstrated by the observation that [Mn(CO)5(CF3)] (the compound with the strongest Mn−RF bond) initiated the radical polymerization of vinylidene fluoride (CH2=CF2) to produce poly(vinylidene fluoride) in good yields by either thermal (100 °C) or photochemical (UV or visible light) activation.  相似文献   

9.
Methane reacted with MnF3 between 350-650°C affording hydrogen fluoride, MnF2, the fluoromethanes CH3F, CH2F2, CHF3 and CF4 and a complex mixture of less volatile fluorocarbons.Methane reacted with FeF3 between 650-950°C giving the fluoromethenes CH3F, CH2F2 and CHF3, C2H4 and carbon, as well as hydrogen fluoride and FeF2.A more detailed study of the CuF2-CH4 reaction between 600-850°C showed that copper metal, hydrogen fluoride and CH3F were always obtained, other products including CH2F2, CHF3, CF4, C2H4, C2H6, C2F6 and carbon. Yields of the fluoromethanes were enhanced by using relatively large amount of CuF2 and by adding CaF2 as an inert support. A nearly constant reaction rate occurred at a fixed temperature. Dilution of methane with nitrogen decreased yields of carbon and CH3F but increased yields of C2H4 and C2H6.A brief study of the reactions with CuF2 and some of the CH4-CuF2 reaction products was also made. Ethane and ethene both afforded traces of trifluoromethane and relatively large yields of carbon and hydrogen fluoride. That the fluorination of methane to tetrafluoromethane could take place sequentially was demonstrated by reactions with CH3F, CH2F2 and CHF3. Some pyrolysis of CH2F2 and CHF3 also occurred under the chosen reaction conditions.The CH4-CuF2 reaction was made part of a cyclic process in which generation of the CuF2 in situ from copper metal by successive reaction with oxygen at 400°C and hydrogen fluoride at temperatures rising to 600°C was followed by reaction with methane; 68% coversion to fluorinated products occurred. The cycle was completed by re-conversion of the copper metal residue back to CuF2 and further reaction with methane when almost identical yields of fluorocarbons and hydrogen fluoride were obtained.  相似文献   

10.
Two routes to RFIF6 compounds were investigated: (a) the substitution of F by RF in IF7 and (b) the fluorine addition to iodine in RFIF4 precursors. For route (a) the reagents C6F5SiMe3, C6F5SiF3, [NMe4][C6F5SiF4], C6F5BF2, and 1,4-C6F4(BF2)2 were tested. C6F5IF4 and CF3CH2IF4 were used in route (b) and treated with the fluoro-oxidizers IF7, [O2][SbF6]/KF, and K2[NiF6]/KF. The observed sidestep reactions in case of routes (a) and (b) are discussed. Interaction of C6F5SiX3 (X = Me, F), C6F5BF2, 1,4-C6F4(BF2)2 with IF7 gave exclusively the corresponding ring fluorination products, perfluorinated cyclohexadiene and cyclohexene derivatives, whereas [NMe4][C6F5SiF4] and IF7 formed mixtures of C6FnIF4 and C6FnH compounds (n = 7 and 9). CF3CH2IF4 was not reactive towards the fluoro-oxidizer IF7, whereas C6F5IF4 formed C6FnIF4 compounds (n = 7 and 9). C6F5IF4 and CF3CH2IF4 were inert towards [O2][SbF6] in anhydrous HF. CF3CH2IF4 underwent C-H fluorination and C-I bond cleavage when treated with K2[NiF6]/KF in HF. The fluorine addition property of IF7 was independently demonstrated in case of perfluorohexenes. C4F9CFCF2 and IF7 underwent oxidative fluorine addition at −30 °C, and the isomers (CF3)2CFCFCFCF3 (cis and trans) formed very slowly perfluoroisohexanes even at 25 °C. The compatibility of IF7 and selected organic solvents was investigated. The polyfluoroalkanes CF3CH2CHF2 (PFP), CF3CH2CF2CH3 (PFB), and C4F9Br are inert towards iodine heptafluoride at 25 °C while CF3CH2Br was slowly converted to CF3CH2F. Especially PFP and PFB are new suitable organic solvents for IF7.  相似文献   

11.
The method of synthesis of the hitherto unknown class of organosilicon compounds, phenyl(acyloxy)fluorosilanes C6H5Si(OCOR) n F3−n (n = 1, 2) and phenyl(acyloxy)fluorochlorosilanes C6H5Si(OCOR) FCl in up to 91% yield has been developed based on the reaction of phenyl(fluoro)chlorosilanes C6H5SiCl n F3−n (n = 1, 2) with trimethylsilyl esters of carboxylic acids Me3SiOC(O)R [R = H, CH3, CF3, CCl3, ClCH2, BrCH2, CH2=CHCH3, CH2=CHPh, CH(CH3)=CH2, Ph].  相似文献   

12.
New disiloxanes containing aromatic or aliphatic fluorinated groups are prepared and identified. The general formula of these compounds is: RF-Q-CH2-CH2-Si(CH3)2-O-Si(CH3)2-CH2-CH2-Q′-R′F · RF and R′F are halogenated groups such as C6F5-, CnF2n+1-, Cl(CFCl-CF2)n, CF3-CFH-CF2-, CF3-, or CCl3-. In most cases, Q or Q′ is an oxygen atom. Symmetrical disiloxanes are obtained by hydrolysis of corresponding fluorinated monochlorodimethylsilanes, and the asymmetrical ones are prepared in two steps by reacting the fluorinated olefins H2C = CH-Q-RF and H2C = CH-Q′-R′F with dihydrotetramethylsiloxane. The structures of these various compounds are elucidated by 1H-, 13C- NMR and IR spectroscopy  相似文献   

13.
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   

14.
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   

15.
Several lanthanide chelates of the fluorochloroalkyl β-diketones Ln(CF2ClCOCHCOR)3 ·nH2O were prepared (2, Ln=Eu; 2a, R=C(CH3)3, n=0; 2b, R=C6F5, n=0; 2c, R=CF2Cl, n=2. 3, Ln=Pr; 3a, R=C (CH3)3, n=0; 3b, R=C6F5, n=l; 3c, R=CF2Cl, n=2. 4, Ln=La, R=C6H5, n=0) and the NMR shift data of compounds 2 and 3 had been determined using alcohols, ether, ketones and amine as substrates. With alcohol, ether and ketone, compounds 2 induces shifts similar to that induced by Eu (fod)3. However due to the high solubility of the chelates in non-polar organic solvents such as CHCl3 and CCl4 and the absence of 1H signal from compounds 2b and 2c, their application as a series of new 1H NMR shift reagents seems promising.  相似文献   

16.
Gas-phase reactions typical of the Earth’s atmosphere have been studied for a number of partially fluorinated alcohols (PFAs). The rate constants of the reactions of CF3CH2OH, CH2FCH2OH, and CHF2CH2OH with fluorine atoms have been determined by the relative measurement method. The rate constant for CF3CH2OH has been measured in the temperature range 258–358 K (k = (3.4 ± 2.0) × 1013exp(?E/RT) cm3 mol?1 s?1, where E = ?(1.5 ± 1.3) kJ/mol). The rate constants for CH2FCH2OH and CHF2CH2OH have been determined at room temperature to be (8.3 ± 2.9) × 1013 (T = 295 K) and (6.4 ± 0.6) × 1013 (T = 296 K) cm3 mol?1 s?1, respectively. The rate constants of the reactions between dioxygen and primary radicals resulting from PFA + F reactions have been determined by the relative measurement method. The reaction between O2 and the radicals of the general formula C2H2F3O (CF3CH2? and CF3?HOH) have been investigated in the temperature range 258–358 K to obtain k = (3.8 ± 2.0) × 108exp(?E/RT) cm3 mol?1 s?1, where E = ?(10.2 ± 1.5) kJ/mol. For the reaction between O2 and the radicals of the general formula C2H4FO (? HFCH2O, CH2F?HOH, and CH2FCH2?) at T = 258–358 K, k = (1.3 ± 0.6) × 1011exp(?E/RT) cm3 mol?1 s?1, where E = ?(5.3 ± 1.4) kJ/mol. The rate constant of the reaction between O2 and the radicals with the general formula C2H3F2O (?F2CH2O, CHF2?HOH, and CHF2CH2?) at T = 300 K is k = 1.32 × 1011 cm3 mol?1 s?1. For the reaction between NO and the primary radicals with the general formula C2H2F3O (CF3CH2? and CF3?HOH), which result from the reaction CF3CH2OH + F, the rate constant at 298 K is k = 9.7 × 109 cm3 mol?1 s?1. The experiments were carried out in a flow reactor, and the reaction mixture was analyzed mass-spectrometrically. A mechanism based on the results of our studies and on the literature data has been suggested for the atmospheric degradation of PFAs.  相似文献   

17.
Two novel assembling systems 3 and 4, with the structures of C6F5CF2?H+N(Me)2CH2CH2(Me2)N+H?CF2C6F5 and C6F5CF2I?N(Me)2CH2CH2(Me)2N?ICF2C6F5, respectively, have been generated from the solution of heptafluorobenzyl iodide 1 and N,N,N,N-tetramethylethylenediamine 2 in dichloromethane. Their structures have been characterized by X-ray diffraction analysis, NMR and IR spectroscopy. Intermolecular N?I halogen bond and F?H hydrogen bond are revealed to be the driving forces for their formation.  相似文献   

18.
This paper investigates the synthetic mechanism of trifluoroiodomethane (CF3I) in the reaction of trifluoromethane and iodine via vapor-phase catalytic reaction. It is suggested that CF2 carbene is the key intermediate and is formed in the pyrolysis process of CHF3 at high temperature. However, in pyrolysis of CHF3 under activated charcoal (AC) existing conditions, no C2F4 was detected. H2 and 2-methyl-2-butene could not trap the CF2 carbene. When treating the remained compounds on the used AC with H2, CH4 is formed on the process. It is proposed that CF2 carbene combines with AC strongly and transfers into CF3 radical on heat. In addition, it is found that the AC is not only the catalyst supporter to form CF3I, but also a co-catalyst to promote the formation of CF2 carbene and CF3 radical.  相似文献   

19.
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   

20.
Twenty nine bis(fluoroalkyl) phosphates (RFO)2P(O)OR were prepared in 18-75% yield by treating phosphorochloridates (RFO)2P(O)Cl, where RF was HCF2CH2, HCF2CF2CH2, H(CF2)4CH2, C2F5CH2, C3F7CH2, (CF3)2CH, (FCH2)2CH and (CH3)2CF3C with methanol, ethanol, propanol and isopropanol in diethyl ether in the presence of triethylamine. The bulky chloridate [(CH3)2CF3CO]2P(O)Cl reacted with methanol, ethanol and propanol, but not with isopropanol - even on heating in the presence of the catalyst 4-dimethylaminopyridine - due to steric hindrance at phosphorus. The relative reactivities of three of the chloridates decreased in the order [(CF3)2CHO]2P(O)Cl > [(FCH2)2CHO]2P(O)Cl > [(CH3)2CF3CO]2P(O)Cl. Also described is the synthesis of phosphates (CF3CH2O)2P(O)OCH2R, where R = CH2Br, CH2Cl, CH2F and CHF2, and diphosphates [H(CF2)nCH2O]2P(O)OCH2(CF2)2CH2OP(O)[OCH2(CF2)nH]2, where n = 1, 2 and 4.  相似文献   

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