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1.
Catalytic cycloalumination of cyclonona-1,2-diene upon treatment with Et3Al and EtAlCl2 in the presence of Cp2ZrCl2, leading to 10-ethyl-10-aluminabicyclo[7.3.01,9]dodec-8-ene (1) and 11-ethyl-11-aluminatricyclo[10.7.01,12.02,10]nonadeca-9,12-diene, respectively, was accomplished in high yields. A possibility for the selective transformation of compound 1 to 1-allyl-9-(pent-4-enyl)cyclonon-1-ene and 10-hydroxybicyclo[7.3.01,9]dodec-8-ene in one preparative step was demonstrated. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2156–2159, November, 2007.  相似文献   

2.
The Tl2MoO4-Ln2(MoO4)3-Hf(MoO4)2 systems where Ln = La-Lu were studied in the subsolidus region using X-ray powder diffraction. Quasi-binary joins were revealed, and triangulation carried out. New ternary molybdates were prepared: Tl5LnHf(MoO4)6 (5: 1: 2) for Ln = Ce-Ho, Tl5LnHf(MoO4)6 (5: 1: 2) for Ln = Er-Lu, TlLnHf0.5(MoO4)3 (1: 1: 1) for Ln = Ce-Nd, and Tl2LnHf2(MoO4)6.5 (2: 1: 4) for Ln = Ce-Lu. The crystallographic parameters of Tl5LnHf(MoO4)6 (5: 1: 2) compounds for Ln = Er-Lu were determined.  相似文献   

3.
The present research work reports the study on crystal structure, vibrational spectroscopy and thermal analysis of organic-inorganic hybrid compound (C6H5(CH2)2NH3)2CdCl4. Single crystals of bis(phenethylammonium)tetrachlorocadmate (C6H5(CH2)2NH3)2CdCl4 (PEA–Cd) were obtained by diffusion at room temperature. This compound crystallizes in the orthorhombic space group C2cb with unit cell parameters a = 7.4444(2) Å, b = 38.8965(3) Å, c = 7.3737(2) Å and Z = 4. Single crystal structure has been solved and refined to R = 0.036 and wR = 0.092. The structure consists of an extended [CdCl4]2– network and two [C6H5(CH2)2NH3]+ cations to form a two-dimensional perovskite system. The infrared (IR) spectrum of the title compound was recorded at room temperature. Differential scanning calorimetry (DSC) was used to investigate the phase transition; this compound exhibits a reversible single solid-solid phase transition.  相似文献   

4.
RuCl2(DMSO)2(NC5H4CO2Na-3)2 is very soluble in the ionic liquid (IL) 1-n-butyl-3-methylimidazolium tetrafluoroborate, [(BMIM)BF4]. The complex was prepared by reacting RuCl2(DMSO)4 with NC5H4CO2Na-3, sodium nicotinate, in toluene, and was characterized by spectroscopic methods. The complex catalyzes the hydrogenation of 1-hexene (600 psi H2, 100 °C) in a two-phase system consisting of cyclohexane/[(BMIM)BF4] with 75% conversion in 24 h and modest substrate isomerization. The complex shows good stability and can be reused several times with little loss in activity.  相似文献   

5.
Ce2O3-K2O-P2O5 ternary system has been investigated by thermoanalytical methods (DTA, DSC), powder X-ray diffraction, XPS and IR spectroscopy. The existence of three double potassium-cerium(III) phosphates has been confirmed and a new binary phosphate K4Ce2P4O15 has been found. Phase diagram and isothermal section at room temperature of the system Ce2O3-K2O-P2O5 have been presented.  相似文献   

6.
Solid-phase interactions in the V2O5-Ta2O5-MoO3 system were studied. The formation of com- pounds TaVO5 and VTa9O25 in the V2O5-Ta2O5 binary system was verified. Tetragonal VTa9O25-base solid solutions of the general formula Ta5 + 4x V5 − 4x O25 (x = 0.25–1) and TaVO5-base solid solutions of the general formula Ta x Mo1 − x V2 − x O8 − 3x (x = 0.625–1) were found to form. Subsolidus phase equilibria in the V2O5-Ta2O5-MoO3 were determined.  相似文献   

7.
The subsolidus region of the Ag2MoO4-MgMoO4-Al2(MoO4)3 ternary salt system has been studied by X-ray phase analysis. The formation of new compounds Ag1 ? x Mg1 ? x Al1 + x (MoO4)3 (0 ≤ x ≤ 0.4) and AgMg3Al(MoO4)5 has been determined. The Ag1 ? x Mg1 ? x Al1 + x (MoO4)3 variable-composition phase is related to the NASICON type structure (space group R \(\bar 3\) c). AgMg3Al(MoO4)5 is isostructural to sodium magnesium indium molybdate of the same formula unit and crystallizes in triclinic system (space group P \(\bar 1\), Z = 2) with the following unit cell parameters: a = 9.295(7) Å, b = 17.619(2) Å, c = 6.8570(7) Å, α = 87.420(9)°, β = 101.109(9)°, γ = 91.847(9)°. The compounds Ag1 ? x Mg1 ? x Al1 + x (MoO4)3 and AgMg3Al(MoO4)5 are thermally stable up to 790 and 820°C, respectively.  相似文献   

8.
Gravimetry in combination with X-ray phase analysis, X-ray crystallography, and X-ray densitometry were used to determine the contents of V5+, V4+, and Ti4+ ions and vacancies in solid solutions formed by the reaction of V2O5 with TiO2 in air at atmospheric pressure.  相似文献   

9.
The aim of this work was to determine the structure of stable heteroassociates (HAs) with the stoichiometric ratios 1:2, 2:1, and 4:1 of molecules formed in the HF-(C2H5)2O binary liquid system. The stretching frequencies of HF molecules found for each HA using a special procedure for processing IR spectra were compared with the calculated frequencies V HF of the stable molecular complexes (HF)m ((C2H5)2O)n (m = 1, 2, 4, 8; n = 1, 2) with different topologies by the density functional method (B3LYP/6-31++G(d,p)). As a result, it was shown that the most stable (among H-bonded complexes with the same stoichiometric ratio of molecules) HAs HF((C2H5)2O)2, (HF)4 ((C2H5)2O)2, and (HF)8-((C2H5)2O)2 formed in HF solutions in diethyl ether. All of them had a cyclic structure and a common peculiarity of structure: only one lone electron pair of the oxygen atom of the (C2H5)2O molecules is involved in hydrogen bonding.  相似文献   

10.
The complexes [Fe(DfgH)2(3-CONH2-Py)2] (I) and [Fe(DfgH)2(4-COOC2H5-Py)2] (II), where DfgH2 is α-benzyl dioxime, were obtained and examined by X-ray diffraction analysis. The equatorial planes of the coordination octahedra of the metal ions consist of two monodeprotonated α-benzyl dioxime residues united through intramolecular hydrogen bonds O-H…O into a pseudomacrocyclic system. The neutral molecules 3-CONH2-Py and 4-COOC2H5-Py are coordinated to the Fe2+ ion through the N atom of the heterocycle. Structure I is layered and structure II is molecular. Intermolecular interactions N-H…O are responsible for the formation of layers in crystal structure I.  相似文献   

11.
Differential scanning calorimetry (DSC) and thermomechanical analysis (TMA) were used to study the thermal behaviour of (50-x)Na2O-xTiO2-50P2O5 and 45Na2O-yTiO2-(55-y)P2O5 glasses. The addition of TiO2 to the starting glasses (x=0 and y=5 mol% TiO2) resulted in a nonlinear increase of glass transition temperature and dilatation softening temperature, whereas the thermal expansion coefficient decreased. All prepared glasses crystallize under heating within the temperature range of 300–610°C. The contribution of the surface crystallization mechanism over the internal one increases with increasing TiO2 content. With increasing TiO2 content the temperature of maximum nucleation rate is also gradually shifted from a value close to the glass transition temperature towards the crystallization temperature. X-ray diffraction measurements showed that the major compounds formed by glass crystallization were NaPO3, TiP2O7 and NaTi2(PO4)3. The chemical durability of the glasses without titanium oxide is very poor, but with the replacement of Na2O or P2O5 by TiO2, it increases sharply.  相似文献   

12.
The complex [UO2(SeO4)(C5H12N2O)2(H2O)] (I) was synthesized and studied by thermal analysis, IR spectroscopy, and X-ray crystallography. The crystals are orthorhombic: a = 13.1661(3) Å, b = 16.4420(5) Å, c = 17.4548(6) Å, Pbca, Z = 8, R = 0.0423. The structural units of crystal I are chains with the composition coinciding with that of the compounds of the AB2M 3 1 crystal chemical group of the uranyl complexes (A = UO 2 2+ , B2 = SeO 4 2? , M1 = C5H12N2O and H2O).  相似文献   

13.
The structure of the [Au(Dien)Cl]2[Re4Te4(CN)12]·5H2O compound prepared in an aqueous medium by the reaction of a gold(III) complex [Au(Dien)Cl]Cl2 with a tetranuclear tetrahedral tellurocyanide cluster complex of rhenium K4[Re4Te4(CN)12]·5H2O is determined by single crystal X-ray diffraction.  相似文献   

14.
Phase equilibria in the three-component systems LiBr-LiVO3-Li2MoO4 and LiBr-Li2SO4-Li2MoO4 have been studied using differential thermal analysis (DTA). Eutectic compositions have been determined (mol %): in the system LiBr-LiVO3-Li2MoO4, 56.0 LiBr, 22.0 LiVO3, and 22.0 Li2MoO4 with a melting temperature of 413°C; and in the system LiBr-Li2SO4-Li2MoO4, 65.0 LiBr, 14.0 Li2SO4, and 21.0 Li2MoO4 with a melting temperature of 421°C. Phase fields have been demarcated.  相似文献   

15.
The solid-phase interaction in the V2O5-Nb2O5-MoO3 system has been investigated, and the formation of a solid solution bounded by the compositions MoNb2V4O18 ? δ, Mo2NbV5O21 ? δ, Mo2Nb3V3O21 ? δ, and Mo4Nb9V9O57 ? δ has been found (δ is nonstoichiometry). In the V2O5?Nb2O5 system, the formation of three compounds is verified, namely, VNbO5 (tetragonal structure), VNb9O25, and V2Nb23O62.5. The first two compounds are isostructural and form a continuous solid solution with tetragonal symmetry. A new compound of the composition Mo3NbVO14 ? δ has been synthesized. This compound is isostructural to the Mo3Nb2O14 compound described in the literature and forms a tetragonal solid solution with it. The phase equilibria in the V2O5-Nb2O5-MoO3 system in the subsolidus region have been determined.  相似文献   

16.
It has been demonstrated that Co2V2O7 and InVO4 react with each other forming a new compound of the Co2InV3O11 formula, when their molar ratio is equal to 1:1, or among CoCO3, In2O3 and V2O5, mixed at a molar ratio of 4:1:3. This compound melts incongruently at the temperature of 960±5°C, depositing crystals of InVO4. It crystallizes in the triclinic system and the unit cell parameters amount to: a=0.6524(6) nm, b=0.6885(5) nm, c=1.0290(4) nm, α=96.5°, β=104.1°, γ=100.9°, Z=2. The phase equilibria being established in the Co2V2O7–InVO4 system over the whole components concentration range up to the solidus line were described.  相似文献   

17.
Nonhygroscopic, colored glasses have been synthesized in the CuNbOF5-BaF2 and CuNbOF5-PbF2 systems proceeding from crystals of the complex compound CuNbOF5 · 4H2O. The glasses have been studied structurally and thermally. The crystallization resistance of the glasses has been studied as a function of glass composition. Lead difluoride glasses are more stable than barium difluoride glasses of the same composition. These glasses have lower glass-transition temperatures than the binary glasses formed in the NbO2F-BaF2 system. The glass structure is built of Nb(O,F)6 polyhedra, which are linked in glass networks through oxygen bridges. Modifier cations influence both the structure of glass networks and the linkage of polyhedra.  相似文献   

18.
Dissolution of vanadium in anhydrous HNO3 followed by exposure of the solution in a dessicator over P2O5 gave liquid vanadyl trinitrate (I). The X-ray diffraction analysis of I was carried out for a single crystal grown on cooling the liquid in a sealed capillary. The structure is composed of VO(NO)3 molecules in which the V atom has an unusually high C.N. 7; it coordinates the terminal O atom and three bidentate nitrate groups to form a distorted pentagonal bipyramid as the coordination polyhedron with the terminal O atom occupying one axial vertex. Using the GAMESS program package, ab initio calculation of the structure of VO (NO3)3 in the liquid phase was carried out. It was shown that in all three physical states, vanadyl trinitrate retains its molecular structure almost invariable. Toluene and naphthalene nitration using I and (NO2)[Fe(NO3)4], NO[Cu(NO3)3], (NO)3/4(NO2)1/4[Zr(NO3)5], and MoO2(NO3)2 proceeds at high rates at low temperatures to give an unusually high para-nitrotoluene percentage in the products as compared with the ortho-isomer. The activity of the studied compounds in the nitration of naphthalene decreases in the series VO(NO3)3 > (NO)3/4(NO2)1/4[Zr(NO3)5] > MoO2(NO3)2.  相似文献   

19.
The KPb2Cl5 and KPb2Br5 crystals are monoclinic (P21/c) with a microtwinned structure. X-ray analysis of chloride resulted in the parameters a = 8.854(2) Å, b = 7.927(2) Å, c = 12.485(3) Å; β = 90.05(3)°, dcalc = 4.78(1) g/cm3 (STOE STADI4, MoKα, 2θmax = 80°), R1 = 0.0702 for 4094 F ≥ 4 σ(F) reflections. For bromide, a = 9.256(2) Å, b = 8.365(2) Å, c = 13.025(3) Å; β = 90.00(3)°, dcalc = 5.62(1) g/cm3 (Bruker P4, MoKα, 2θmax = 70°), R1 = 0.0692 for 3076 F ≥ 4 (F) reflections.  相似文献   

20.
The single crystals of [UO2(C2O4){CONH2N(CH3)2}2] were synthesized and studied by X-ray diffraction. The crystals are monoclinic, a = 7.461(2) Å, b = 8.828(2) Å, c = 11.756(2) Å, β = 107.21(3)°, space group Pc, Z = 2, R = 2.94%. The structure comprises infinite chains [UO2(C2O4){CONH2N(CH3)2}2] extended along [001] and corresponding to the AT11M 2 1 crystallochemical group (A = UO 2 2+ , T11 = C2O 4 2? , M1 = N,N-CONH2N(CH3)2) of uranyl complexes. The chains are connected into a three-dimensional framework by hydrogen bonds involving the oxygen atoms of oxalate and uranyl ions and the N,N-dimethylcarbamide methyl groups.  相似文献   

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