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1.
Synthesis and Properties of Tetrakis(Perfluoroalkyl)Tellurium Te(Rf)4 (Rf = CF3, C2F5, C3F7, C4F9) Te(CF3)4 is obtained from the reaction of Te(CF3)Cl2 with Cd(CF3)2 complexes as a complex with e. g. CH3CN, DMF. It is a light and temperature sensitive hydrolysable liquid. The reaction with fluorides yields the complex anion [Te(CF3)4F], with fluoride ion acceptors the complex cation [Te(CF3)3]+. With traces of water an acidic solution is formed. Te(CF3)4 acts as a trifluoromethylation reagent. The reaction with XeF2 gives hints for the formation of Ye(CF3)4F2. Properties and NMR spectra are discussed. The much more stable complexes of Te(Rf)4 (Rf = C2F5, C3F7, C4F9) are formed from the reaction of TeCl4 with the corresponding Cd(Rf)2 complexes.  相似文献   

2.
Perfluoroorgano Tellurium Compounds: New Investigations on the Preparation of Te(Rf)2 and CH3TeRf (Rf = C2F5, C3F7, C6F5) Methyl(perfluoroorgano) tellurium and bis(perfluoroorgano) tellurium compounds are synthesized in high yields from the photochemical or the thermal reactions of (CH3)2 Te with perfluoroorgano iodides in the presence of (C2H5)3N. They are isolated in pure states. Another general method for the preparation of bis(perfluoroorgano) tellurium is the thermal reaction of TeCl4 with bis(perfluoroorgano) mercury. The preparations and properties of the partially new compounds are described.  相似文献   

3.
The stereochemical nonrigidity of RfCo(PF3)x(CO)4-x(Rf=CF3,C2F5,C3F7,x=0-4) was studied at the theoretical level of B3LYP/6-31 1+G^* via Gaussian 09.The intramolecular rearrangements in these penta-coordinated compounds are mainly caused by the vibrations of perfluoroalkyl groups.All the barriers along the reaction coordinate are less than 66.9 kJ/mol,which indicates that the rearrangements are kinetically favorable and hard to elucidate by experiment.Besides,ligand PF3 is a ligand similar to CO,the energy difference between the reactant and product is small.  相似文献   

4.
5.
The reactions of some perfluoroalkyl radicals with carbon tetrachloride have been studied using the photolysis of the corresponding perfluoroalkyl iodide as the free radical source. The Arrhenius parameters, based on the value of 2.3 × 1013 cm3 mol?1 s?1 for the self-combination rate constant of all radicals are:
Reaction log(A/cm3 mol?1 s?1) E/kcal mol?1
CF3 + CCl4 12.8 11.3
C2F5 + CCl4 12.8 11.6
n-C3F7 + CCl4 12.9 12.0

Citing Literature

Volume 16 , Issue 11 November 1984

Pages 1351-1356  相似文献   


6.
New Syntheses and Crystal Structures of Bis(fluorophenyl) Mercury, Hg(Rf)2 (Rf = C6F5, 2, 3, 4, 6‐F4C6H, 2, 3, 5, 6‐F4C6H, 2, 4, 6‐F3C6H2, 2, 6‐F2C6H3) Bis(fluorophenyl) mercury compounds, Hg(Rf)2 (Rf = C6F5, C6HF4, C6H2F3, C6H3F2), are prepared in good yields by the reactions of HgF2 with Me3SiRf. The crystal structures of Hg(2, 3, 4, 6‐F4C6H)2 (monoclinic, P21/n), Hg(2, 3, 5, 6‐F4C6H)2 (monoclinic, C2/m), Hg(2, 4, 6‐F3C6H2)2 (monoclinic, P21/c) and Hg(2, 6‐F2C6H3)2 (triclinic, P1) are described.  相似文献   

7.
Exposing [Bi(OR)3(toluene)]2 (1, R = OC6F5) to different solvents leads to the formation of larger polymetallic bismuth oxo alkoxides via ether elimination/oligomerization reactions. Three different compounds were obtained depending upon the conditions: Bi4(mu 4-O)(mu-OR)6(mu 3-OBi(mu-OR)3)2(C6H5CH3) (2), Bi8(mu 4-O)2(mu 3-O)2(mu 2-OR)16 (3), Bi6(mu 3-O)4(mu 3-OR)(mu 3-OBi(OR)4)3 (4). Compounds 2 and 3 can also be synthesized via an alcoholysis reaction between BiPh3 and ROH in refluxing dichloromethane or chloroform. Related oxo complexes NaBi4(mu 3-O)2(OR)9(THF)2 (5) and Na2Bi4(mu 3-O)2(OR)10(THF)2 (6) were obtained from BiCl3 and NaOR in THF. The synthesis of 1 and Bi(OC6Cl5)3 via salt elimination was successful when performed in toluene as solvent. For compounds 2-6 the single-crystal X-ray structures were determined. Variable-temperature NMR spectra are reported for 2, 3, and 5.  相似文献   

8.
Reactions of Thiazyl Halides XSN (X = F, Cl) with Perfluorinated Imines Rf2 NH (Rf = F, CF3, CF3S, (CF3)2C?, (CF3)2S?): Attempted Preparations of Aminothiazyls (?N? S?N) Thiazyl halides or their precursors Cl3S3N3 and FC(O)N?SF2 react with perfluoro imines to provide the corresponding aminothiazyls as unstable and reactive intermediates. While with HNF2 or KF · HNF2 the final products N2F4 and S4N4 are formed, [(CF3)2N]2Hg reacts with Cl3S3N3 to give CF3N?CF2, FSN, and HgCl2. The expected product CF3SN?S?NSCF3 ( 4 ) is obtained from (CF3S)2NH or Hg[N(SCF3)2]2 and FSN probably via (CF3S)2 NSN. Surprisingly, (CF3)2C?NLi forms with ClSN, Cl3S3N3 or [S3N2Cl]Cl in the presence of NH4Cl 4,5-Dihydro-3,3,5,5-tetrakistrifluoromethyl-3H-1λ4,2,4,6-thiatriazine ( 6 ) and (CF3)2C?NSxN?C(CF3)2 (X = 1, 2) ( 7a, b ) as byproducts. A CsF catalyzed reaction at 70 to 80°C between (CF3)2C?NLi and FSN provides low yields of (CF3)2C?N? S? N?S?NCF(CF3)2 ( 8 ) together with 7a, b. The latter are the only products without CsF. When (CF3)2S?NH is treated with FSN, the compounds CF3SCF3, S4N4, and N2 are identified. It is shown by 19F and 14N-n.m.r. spectroscopy that (CF3)S?NSN is an unstable intermediate.  相似文献   

9.
Syntheses and Properties of Perfluoroorgano Esters of the Diethyldithiocarbamic Acid, (C2H5)2NC(S)SRf (Rf = CF3, C2F5, i‐C3F7, n‐C4F9, C6F5) Tetraethylthiuram disulfide reacts under different conditions with perfluoroorgano silver(I), AgRf, and perfluoroorgano cadmium compounds, Cd(Rf)2, to give the corresponding perfluoroorgano esters of diethyldithiocarbamic acid, (C2H5)2NC(S)SRf (Rf = CF3, C2F5, i‐C3F7, n‐C4F9, C6F5), and metal diethyldithiocarbamates, AgSC(S)N(C2H5)2 and Cd[SC(S)N(C2H5)2]2. The mechanisms of the reactions with AgRf and Cd(Rf)2 are discussed.  相似文献   

10.
The reactions between F2 and the lowest members of the homologous series of perfluoroalkyl iodides (CF3I, C2F5I, and n-C3F7I) have been studied. For these compounds, an exponential decrease in the alkyl iodide concentration over time following an induction period is observed for certain experimental conditions. Other conditions lead to chaotic-like kinetic behavior where the rate of alkyl iodide consumption continually changes. Kinetic rate data with CF3I show that the disappearance rate depends upon both the type of surface and surface preparation. For all three compounds, Arrhenius plots reveal activation energies on the order of 10 kcal/mol, consistent with effective initiation steps of F2 + RI → RIF + F, where R represents the CF3, C2F5, or n-C3F7 radical respectively. The end products of the F2 + RI reactions are RF, R2, and IF5, suggesting that the R radicals play an important kinetic role. Introducing O2 into the F2 + RI reaction systems results in successive oxidation of R by O2, leading to the formation of CF2O as an additional end product. IF(B → X) emission is observed from the RI-rich F2 + RI reactions, confirming the existence of IF as an intermediate. © 1996 John Wiley & Sons, Inc.  相似文献   

11.
Reaction of C(60) with CF(3)I at 550 degrees C, which is known to produce a single isomer of C(60)(CF(3))(2,4,6) and multiple isomers of C(60)(CF(3))(8,10), has now been found to produce an isomer of C(60)(CF(3))(6) with the C(s)-C(60)X(6) skew-pentagonal-pyramid (SPP) addition pattern and an epoxide with the C(s)-C(60)X(4)O variation of the SPP addition pattern, C(s)-C(60)(CF(3))(4)O. The structurally similar epoxide C(s)-C(60)(C(2)F(5))(4)O is one of the products of the reaction of C(60) with C(2)F(5)I at 430 degrees C. The three compounds have been characterized by mass spectrometry, DFT quantum chemical calculations, Raman, visible, and (19)F NMR spectroscopy, and, in the case of the two epoxides, single-crystal X-ray diffraction. The compound C(s)-C(60)(CF(3))(6) is the first [60]fullerene derivative with adjacent R(f) groups that are sufficiently sterically hindered to cause the (DFT-predicted) lengthening of the cage (CF(3))C-C(CF(3)) bond to 1.60 A as well as to give rise to a rare, non-fast-exchange-limit (19)F NMR spectrum at 20 degrees C. The compounds C(s)-C(60)(CF(3))(4)O and C(s)-C(60)(C(2)F(5))(4)O are the first poly(perfluoroalkyl)fullerene derivatives with a non-fluorine-containing exohedral substituent and the first fullerene epoxides known to be stable at elevated temperatures. All three compounds demonstrate that the SPP addition pattern is at least kinetically stable, if not thermodynamically stable, at temperatures exceeding 400 degrees C. The high-temperature synthesis of the two epoxides also indicates that perfluoroalkyl substituents can enhance the thermal stability of fullerene derivatives with other substituents.  相似文献   

12.
The reaction of (C6F5)2HGeGeH(C6F5)2 with triethylbismuth affords a new polynuclear germylbismuth derivative, [(C6F5Ge]4Bi2 (1). The metal framework of molecule1 has the form of a gable roof built by two central Bi atoms and four peripheral Ge atoms with covalent Bi-Bi bonds [3.045(3) Å], Bi-Ge [2.724(5)-2.755(4) Å] and Ge-Ge [2.444(6), 2.465(6) Å].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 921–924, May, 1994.  相似文献   

13.
14.
15.
New complexes (Bu(4)N)(2)[Mo(6)X(8)(n-C(3)F(7)COO)(6)] (X = Br, I) display extraordinarily bright long-lived red phosphorescence both in solution and solid phases, with the highest emission quantum yields and the longest emission lifetimes among hexanuclear metal cluster complexes of Mo, W and Re, hitherto reported.  相似文献   

16.
The overall photobromination reactions have been studied using a competitive technique. Relative Arrhenius parameters were obtained for the rate-determining step These were placed on an absolute basis using previous-absolute values of A and E for RFI=CF3I. The activation energies were used to calculate bond dissociation energies D(R? I) with the following results:
RF? E16 D(RF?I)(kcal/mole)
CF3I a a E16 from [1]
10.8 52.6
C2F5I 8.8 50.6
n-C3F7I 7.4 49.2
i-C3F7I 7.5 49.2
n-C4F9I 6.7 48.4
  • a E16 from [1]
The D(RI) are compared with related D(R? I) and it is concluded that for a given alkyl group RH and the corresponding perfuloroalkyl group RF, D(RI) > D(RI) whereas it has previously been found that D(RX;) < D(RX) where X is not iodine.  相似文献   

17.
New examples of [C6F5Xe]+ salts of the weakly coordinating [BY4]- (Y = CN, CF3, or C6F5) anions were synthesized by metathesis of [C6F5Xe][BF4] with MI[BY4] (MI = K or Cs; Y = CN, CF3, or C6F5) in CH3CN at -40 degrees C, and were crystallized from CH2Cl2 or from a CH2Cl2/CH3CN solvent mixture. The low-temperature (-173 degrees C) X-ray crystal structures of the [C6F5Xe]+ cation and of the [C6F5XeNCCH3]+ adduct-cation are reported for [C6F5Xe][B(CF3)4], [C6F5XeNCCH3][B(CF3)4], [C6F5Xe][B(CN)4], and [C6F5XeNCCH3][B(C6F5)4]. The [C6F5Xe]+ cation, in each structure, interacts with either the anion or the solvent, with the weakest cation-anion interactions occurring for the [B(CF3)4]- anion. The solid-state Raman spectra of the [C6F5Xe]+ and [C6F5XeNCCH3]+ salts have been assigned with the aid of electronic structure calculations. Gas-phase thermodynamic calculations show that the donor-acceptor bond dissociation energy of [C6F5XeNCCH3]+ is approximately half that of [FXeNCCH3]+. Coordination of CH3CN to [C6F5Xe]+ is correlated with changes in the partial charges on mainly Xe, the ipso-C, and N, that is, the partial charge on Xe increases and those on the ipso-C and N decrease upon coordination, typifying a transition from a 2c-2e to a 3c-4e bond.  相似文献   

18.
19.
Russian Chemical Bulletin - Tris(4-fluorophenyl)antimony reacts with iodoacetic and pentafluorobenzoic acids in the presence of tert-butylhydroperoxide to give tris(4-fluorophenyl)antimony...  相似文献   

20.
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