共查询到20条相似文献,搜索用时 31 毫秒
1.
M. Rosrio Riberio Manuel F. Portela Alain Deffieux Henri Cramail Manuel F. Rocha 《Macromolecular rapid communications》1996,17(7):461-469
The homopolymerization of styrene and its copolymerization with ethylene in the presence of a vanadium-based supported catalyst, {VCI3, 1 AICI3}, associated to triethylaluminium is examined. As indicated by means of 13C nuclear magnetic resoance and differential scanning calorimetry analysis, the homopolystyrenes obtained present a highly isotactic microstructure and are semicrystalline (melting temperature 220°C). In the case of styrene/ethylene random copolymerization, the formation of both, polyethylene blocks and isotactic polystyrene sequences was identified by analysis of the crude polymer. Solubility characteristics and structural characteristics from nuclear magnetic resonance spectra of these products support the formation of copolymers with ethylene and isotactic styrene blocks rather than that of two distinct homopolymers. 相似文献
2.
N. A. Chernyavskaya V. I. Aleksinskaya B. G. Zavin A. I. Belokon 《Russian Chemical Bulletin》1997,46(12):2147-2148
Catalytic activation of Si−C bonds in poly(vinyltrimethylsilane) was studied using a model reaction of catalytic transformations
of oligocarbosilanes Me3Si(CH2)
n
SiMe3 (n=2, 3) in dichlorodimethylsilane in the presence of AlCl3 as an example. The formation of ClMe2Si(CH2)
n
SiMe3 was established by chromato-mass spectrometry and GLC.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2265–2266, December, 1997. 相似文献
3.
AlCl3 · 3NH3 — a Compound with the Crystal Structure of a Tetraammine Dichloro Aluminium-Diammine Tetrachloro Aluminate: [AlCl2(NH3)4]+[AlCl4(NH3)2]? . AlCl3 · 3 NH3 ? [AlCl2(NH3)4]+ [AlCl4(NH3)2]? forms during the reaction of two mole NH3 with AlCl3(NH3) at T ≥ 200°C. Repeated heating and cooling within 48 h between 200°C and 250°C gives a homogeneous product with total uptake of the necessary amount of NH3. Slow sublimation in a vacuum line apparatus at 200°C gives crystals of the triammoniate sufficient for a X-ray structure determination: The compound contains elongated [AlCl2(NH3)4]+ octahedra and compressed [AlCl4(NH3)2]? octahedra. Besides ionic bonding hydrogen bridge bonds with 3.369 Å ? d(N—H … Cl) ? 3.589 Å stabilize the atomic arrangement. 相似文献
4.
ACl3 · 2NH3 – a Compound with the Crystal Structure of a Tetraammine Dichloroaluminiumtetrachloroaluminate – [AlCl2(NH3)4]+[AlCl4]? Ammoniates of aluminiumchloride AlCl3 · xNH3 are in discussion as starting materials for the synthesis of aluminiumnitride. Therefore the reactions of melts of monoamminealuminiumchloride with ammonia were investigated. They react at 150°C within 10 min with one mole of ammonia to the diammoniate, [AlCl2(NH3)4]+[AlCl4]?. The pure compound can be obtained by sublimation at 200°C in vacuumline apparatus. X-ray structure determination on [AlCl2(NH3)4]+[AlCl4]? was carried out: see “Inhaltsübersicht”. 相似文献
5.
Reactions of organo(trichloromcthyl)silanes RMc2SiCCl3 (R = Me, Ph, Mc3Si) with aluminum chloride have been studied. The interaction of trimetltyl(tricltlorometltyl)silane with AlCl3 carried out in cyclohexane or in benzene leads to Me3SiCHCI2 (in 75 % yield) or ClMe2SiCPh2Me (in 70 % yield), respectively; whereas no conversions are observed inn-hexane and methylene chloride. Treatment of dimetltyl(phenyl)(ricltloromethyl)silane with aluminum chloride in an-C5H12/CH2CI2 mixture gives an aromatic cross-linked insoluble polymer. The reaction of pentamethyl(trichloromcthyl)disilane (R = Mc3Si) with AICl3 in pentane affords the rearrangement product, Me3SiCCl2SiMc2Cl, in 65 % yield. In methylene chloride the further cleavage of the disilane occurs to yield Me2SiCl2 and CH2=CHMe2SiCl.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1511-1515, June, 1996. 相似文献
6.
Adducts and Salts Formed by Sulphurchlorides with AlCl3 The instability of the adduct 2 S2Cl2 · AlCl3 is proven. S2Cl2 · AlCl3 and S2Cl2 · 2 AlCl3 reported in the literature could not be found under proper conditions, their formation seems improbable. The product 2 SCl4 · 3 AlCl3, obtained by the reaction of [SCl3]+[AlCl4]? with elementary sulphur, is characterized as a double salt [SCl3]2+[AlCl4]? [Al2Cl7]?. The [Al2Cl7]? anion is also found as an intermediate during the thermal decomposition of [SCl3]+[AlCl4]? and when metallic aluminium reacts directly with S2Cl2. For SCl2 · AlCl3, the ionic character with a chlorsulfenium cation [SCl]+ is proven spectroscopically. 相似文献
7.
Aluminum-27 NMR was used to investigate AlCl3–MCl (M=Li, Na, K, Butylpyridinium) molten mixtures. In AlCl3 rich mixtures, the27Al resonance line was resolved into two components corresponding to the AlCl
4
–
and Al2Cl
7
–
species, which were shown to undergo chemical exchange line broadening. This broadening was found to be cation and temperature dependent. 相似文献
8.
X-ray fluorescence spectrometry (XRF) was applied to determine aluminium in AlCl3- and Al2O3-modified silica catalyst supports that were prepared by gas-solid reactions in an atomic layer epitaxy (ALE) process using
aluminium chloride or aluminium chloride and water as adsorbates and silica as support. INAA and AAS were used as reference
methods to determine the aluminium content of the supports. The calibration of XRF results was done by plotting the Al/Si
intensity ratios against the aluminium content as determined by atomic absorption spectrometry (AAS) and verified by instrumental
neutron activation analysis (INAA). Correlation factors for the calibration graphs were 0.984 for AlCl3/SiO2 and 0.995 for Al2O3/ SiO2 samples in the aluminium content range 0–2.6 g Al per 100 g of sample.
Received: 19 October 1998 / Accepted: 14 December 1998 相似文献
9.
X-ray fluorescence spectrometry (XRF) was applied to determine aluminium in AlCl3- and Al2O3-modified silica catalyst supports that were prepared by gas-solid reactions in an atomic layer epitaxy (ALE) process using
aluminium chloride or aluminium chloride and water as adsorbates and silica as support. INAA and AAS were used as reference
methods to determine the aluminium content of the supports. The calibration of XRF results was done by plotting the Al/Si
intensity ratios against the aluminium content as determined by atomic absorption spectrometry (AAS) and verified by instrumental
neutron activation analysis (INAA). Correlation factors for the calibration graphs were 0.984 for AlCl3/SiO2 and 0.995 for Al2O3/ SiO2 samples in the aluminium content range 0–2.6 g Al per 100 g of sample.
Received: 19 October 1998 / Accepted: 14 December 1998 相似文献
10.
《Chemical physics letters》1987,141(3):251-254
Self-diffusion coefficients of 27Al and H2O were determined by the NMR pulsed-field-gradient method in a series of AlCl3 solutions. From these data, bulk water self-diffusion coefficients are derived. It is shown that the relative influence on the bulk water translational motion agrees reasonably with the relative influence on the reorientational motion as reported in previous work. The bulk water self-diffusion is interpreted using a hydrodynamical model. 相似文献
11.
Summary Metalloid-nonmetal and Metal-nonmetal interactions of BF3, BCl3, AlF3 and AlCl3 were examined at the matrix Hartree Fock level ofab initio theory. Structural and energetic properties, many-body expansion convergence, short- and long-range components of interaction energies, and group-theoretical parameters were found to uniquely characterize these interactions. 相似文献
12.
Aluminium trichloride forms the adducts AlCl3 · NH2CH3, AlCl3 · 2NH2CH3, AlCl3 · 4NH2CH3; AlCl3 · NH3CH3Cl, AlCl3 · 2NH3CH3Cl. The interaction between AlCl3, PCl5 and NH3CH3Cl in the molar ratio 1:3:2 proceeds according to the reaction equation in “Inhaltsübersicht”. On applying other stoichiometric amounts, [Cl2(NHCH3)P? N(CH3)? AlCl3] · HCl and [Cl3P? N(CH3)? AlCl3] · HCl are obtained; the latter reacts as [Cl3P? NHCH3][AlCl4]. At the molar ratio AlCl3:PCl5:NH3CH3Cl = 1:2:4 a compound is formed being presumably the six-membered heterocycle formulated in “Inhaltsübersicht”. With [Cl3P?N? PCl3] and aluminium chloride [Cl3P?N? PCl3][AlCl4] is formed. 相似文献
13.
Petrova T. D. Popova I. S. Kolesnikova I. V. Platonov V. E. 《Russian Chemical Bulletin》1994,43(6):1027-1033
The reactions of pentafluoroaniline with aromatic CX3-derivatives (X = F, Cl) in the presence of AlCl3 were studied. It was shown that compounds with a CF3 group can be used in reactions with polyfluoroaromatic amines instead of CCl3-derivatives for the synthesis of imidoyl chlorides. In the case of compounds with several CX3 groups, the formation of the imidoyl chloride moiety predominantly involves one of the CX3 groups under the conditions studied. The introduction of a second CX3 group can be carried out only under more drastic conditions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1089–1094, June, 1994. 相似文献
14.
Rekulapally Sriram Chebolu Naga Sesha Sai Pavan Kumar Nerella Raghunandan Vadla Ramesh 《合成通讯》2013,43(23):3419-3428
Abstract A simple and efficient method is described for the oxidation of 7-azaindoles and indoles to 7-azaisatins and isatins using pyridinium chlorochromate–silica gel (PCC-SiO2) with the aid of Lewis acid catalyst aluminium chloride (AlCl3) in dichloroethane. Simplicity of the reaction conditions, easy workup procedure, and good yields are the key features of this protocol. 相似文献
15.
Shojiro Kaita Takako Otaki Eiichi Kobayashi Sadahito Aoshima Junji Furukawa 《Journal of polymer science. Part A, Polymer chemistry》1997,35(13):2591-2597
The polymerization of polar monomers such as methyl methacrylate (MMA), methyl acrylate (MA), methacrylonitrile (MAN), and acrylonitrile (AN) was carried out with gadolinium-based Ziegler–Natta catalysts [Gd(OCOCCl3)3-(i-Bu)3Al-Et2AlCl] in hexane at 50°C under N2 to elucidate the effect of the monomer's HOMO(highest occupied moleculor orbital) and LUMO (lowest unoccupied molecular orbital) levels on the polymerizability. In the case of homopolymerization, all monomers were found to polymerize and the order of relative polymerizability was as follows: MM > MA > MAN > AN. On the other hand, the result of copolymerization of St with MMA shows that the values of the monomer reactivity ratios are r1 = 0.06 and r2 = 1.98 for St(M1)/MMA(M2). The monomer reactivity ratios of styrene (St), p-methoxystyrene (PMOS), p-methylstyrene (PMS), and p-chlorostyrene (PCS) evaluated as r1 = 0.55 and r2 = 1.07 for St(M1)/PMOS(M2), r1 = 0.38 and r2 = 0.51 for St(M1)/PMS(M2), and r1 = 0.72 and r2 = 1.25 for St(M1)/PCS(M2) were compared with those for St(M1)/MMA(M2). The copolymerization behavior is apparently different from the titanium-based Ziegler—Natta catalyst, regarding a larger monomer reactivity ratio of PCS. The lower LUMO level of PCS and MMA may enhance a back-donation process from the metal catalyst, therefore resulting in high polymerizability. These results are discussed on the basis of the energy level of the gadolinium catalyst and the HOMO and LUMO levels of the monomers. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2591–2597, 1997 相似文献
16.
《Polyhedron》1986,5(3):821-832
Raman and IR spectra were obtained of molten AlCl3NH3, AlCl3ND3 and AlBr3NH3 in addition to chloroaluminate mixtures of the AlCl3NH3. The main spectral features of the gaseous AlCl3NH3 molecules having a C3v-symmetry are retained in the molten and glassy states. Some additional bands were observed both in the pure liquid and in mixtures with chloroaluminate melts. The spectra indicated that the discussion reaction 2AlCl3NH3 = AlCl−4 + [AlCl2(NH3)2]+ occurs with K ⋍ 3 × 10−3 (mole fraction basis). Frequency shifts found on liquefaction demonstrate that extensive hydrogen bonding takes place between AlCl3NH3 molecules. This observation is supported by the glass-forming nature of AlCl3NH3. The molecule Al2Cl6NH3 seems to exist in binary AlCl3-AlCl3NH3 melts. 相似文献
17.
Harald Schfer 《无机化学与普通化学杂志》1975,414(2):151-159
Gas Complexes with AlCl3, All3 (or FeCl3), their Abundance and Stability Gas complexes MClm · xAlCl3 (FeCl3) cover a large area of the periodic table. The thermodynamic discussion shows the great stability of these complexes below 1200°K. The ΔH°-values for the stepwise complex formation MCl2/MAlCl5/MAl2Cl8 are discussed. The important factor is the supplement of the coordination sphere. 相似文献
18.
D. Todorovsky K. Kostadinov E. Taneva Zh. Dimitrova 《Journal of Radioanalytical and Nuclear Chemistry》1982,75(1-2):107-111
A radioanalytical procedure for the determination of the chemical forms of35S in reactor irradiated crystals AlCl3, FeCl3 and AlCl3?FeCl3 is described. The method includes:35S extraction with trichloroethylene, precipitation of35S2? as iron sulfide and of (35SO 4 2? +35SO 3 2? ) as Ba-salts. All fractions are converted to, and measured as, BaSO4. 相似文献
19.
Synthesis and Crystal Structure of the Lewis Acid‐Base Adduct AlCl3·C3N3Cl3 The reaction between cyanuric chloride (C3N3Cl3) and the strong Lewis acid AlCl3 yielded colorless crystals of the adduct AlCl3·C3N3Cl3. The crystal structure was determined by single crystal X‐ray diffraction at room temperature and was solved in the space group with Z = 4, a = 7.3802(7) Å, b = 9.688(1) Å, c = 16.272(2) Å, α = 72.80(1)°, β = 89.97(1)°, γ = 87.23(1)°, and V = 1110.0(2) Å3. In the crystal structure, AlCl3 is closely associated to the triazine ring with Al–N distances of 2.042(3) Å and 2.067(4) Å, respectively. The AlCl3·C3N3Cl3 units are connected with each other via intermolecular N···Cl donor–acceptor interactions, forming tape‐like arrangements in the ac‐plane, with tapes running parallel to the a‐axis. 相似文献
20.
《Journal of fluorine chemistry》1987,37(2):151-169
The acrylic ester F2CCFCO2CD3 is prepared from a mixture of difluorotetrachloroethanes CFCI2CFCI2 and CF2CICCI. The dehalogenation of these Freons, followed by the addition of CFCI3 by means of AICI3 leads to a mixture of chlorofluoropropanes. The hydrolysis with oleum gives the acid chlorides which are then esterified by CD3OD. The dehalogenation of the mixture by the zinc stirred in oxalic acid enables isolation of the expected ester by distillation. This compound, the refractive index of which n20D=1.3667 does not show a major absorption in the near infra-red between 0.6 and 1.4 μm. Thus the corresponding polymer is likely to provide a good material for the core of optical fibers. 相似文献