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1.
Matic Lozinšek Evgeny Goreshnik Anton Meden Gašper Tav?ar 《Journal of solid state chemistry》2009,182(10):2897-2903
In the system BaF2/BF3/PF5/anhydrous hydrogen fluoride (aHF) a compound Ba(BF4)(PF6) was isolated and characterized by Raman spectroscopy and X-ray diffraction on the single crystal. Ba(BF4)(PF6) crystallizes in a hexagonal space group with a=10.2251(4) Å, c=6.1535(4) Å, V=557.17(5) Å3 at 200 K, and Z=3. Both crystallographically independent Ba atoms possess coordination polyhedra in the shape of tri-capped trigonal prisms, which include F atoms from BF4− and PF6− anions. In the analogous system with AsF5 instead of PF5 the compound Ba(BF4)(AsF6) was isolated and characterized. It crystallizes in an orthorhombic Pnma space group with a=10.415(2) Å, b=6.325(3) Å, c=11.8297(17) Å, V=779.3(4) Å3 at 200 K, and Z=4. The coordination around Ba atom is in the shape of slightly distorted tri-capped trigonal prism which includes five F atoms from AsF6− and four F atoms from BF4− anions. When the system BaF2/BF3/AsF5/aHF is made basic with an extra addition of BaF2, the compound Ba2(BF4)2(AsF6)(H3F4) was obtained. It crystallizes in a hexagonal P63/mmc space group with a=6.8709(9) Å, c=17.327(8) Å, V=708.4(4) Å3 at 200 K, and Z=2. The barium environment in the shape of tetra-capped distorted trigonal prism involves 10 F atoms from four BF4−, three AsF6− and three H3F4− anions. All F atoms, except the central atom in H3F4 moiety, act as μ2-bridges yielding a complex 3-D structural network. 相似文献
2.
Fahai Cao Li Tian Nianjun Luo Dingye Fang Weiyong Ying 《Reaction Kinetics and Catalysis Letters》2008,94(1):107-114
A new application of ionic liquids is developed for a novel process of synthesizing pentyltoluene from toluene and a C5 diolefin
(1,3-pentadiene). The catalyst [bupy]BF4-AlCl3 behaves better than [bupy]BF4-FeCl3. 相似文献
3.
Dibenzyloxydihydrobenzoxathiin 1, which resisted debenzylation with SiCl4/LiI, was effectively debenzylated with SiCl4/LiI in the presence of a catalytic amount of BF3. The HCl salt of the bis-debenzylated product 2 was isolated in 90% yield and 99% purity. This enhanced dealkylation activity has also been observed with other substrates. 相似文献
4.
Organocopper and cuprate reagents associated with Lewis acids, are highly reactive towards allylic acetals and ethers. Displacements of the alkoxy group occurs by SN2' attack according to the various parameters of the reaction. 相似文献
5.
Ab initio calculation are performed on the BF3 and BCl3 molecules, and the Koopmans' theorem ionization potentials are compared with the experimental ones obtained from photoelectron spectra. 相似文献
6.
The compound [{Pt4(en)4(NHCOtBu)4}{Tl(18-crown-6)}2](PF6)6 has been synthesized by a simple one-pot multicomponent reaction. Its structure was determined by X-ray single crystal diffraction analysis. The cation of the compound consists of one linearly arranged [Pt4(en)4(NHCOtBu)4]4+ chain and two [Tl(18-crown-6)]+ ions located at the two ends of the platinum chain. The complex crystallizes in a triclinic P1 with a=1.060 5(1), b=1.252 3(1), c=2.015(2) nm, α=107.430(2)°, β=91.032(2)°, γ=101.910(2)°, V=2.489 6(4) nm3, Z=2, R1=0.074 4, wR2(I>2σ(I))=0.222 5, S=1.062. CCDC: 294083. 相似文献
7.
M.C. Barral R. Jimnez-Aparicio J.L. Priego E.C. Royer F.A. Urbanos A. Monge C. Ruíz-Valero 《Polyhedron》1993,12(24):2947-2953
The reaction between Ru2Cl(μ-O2CCH3)4 and molten p-tert-butylbenzamide led to the formation of Ru2Cl(μ-HNOCC6H4-p-CMe3)4. The polymeric structure of this insoluble compound was broken with AgBF4, in anhydrous thf, giving [Ru2(μ-HNOCC6 H4-p-CMe3)4(thf)2]BF4. The reaction of this cationic complex with OPPh3 gave [Ru2(μ-HNOCC6H4-p-CMe3)4(OPPh3)2]BF4. The compounds have been characterized by elemental analysis, spectroscopic data and magnetic measurements and the crystal structure of [Ru2(μ-HNOCC6H4-p-CMe3)4(OPPh3)2]BF4 was determined by X-ray crystallography. The asymmetric unit is composed of halves of two different crystallographically independent centrosymmetric cations. Each ruthenium(II,III) dimer is bonded to four bridging p-tert-butylbenzamidate ligands and to two axial triphenylphosphine oxide molecules. The Ru---Ru distances in the two dimeric cations of the unit cell are 2.281(2) and 2.280(2) Å. The compound has a non-polar 2 : 2 arrangement of the tert-butylbenzamidate ligands. 相似文献
8.
Activated aryl halides undergo smooth nucleophilic substitution reactions with secondary amines in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6) or 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) ionic liquids (ILs) at room temperature to afford the corresponding arylamines in excellent yields under mild and neutral conditions. 相似文献
9.
10.
Stephen P. Walch Charles W. Bauschlicher Bjorn O. Roos Constance J. Nelin 《Chemical physics letters》1983,103(3):175-179
Calculated CAS SCF potential curves are reported for the 3Σg? state of V2 and the 1Σg+ state of Cr2. At the CAS SCF level the 3Σg? state of V2 is calculated to be bound (Rc = 1.77 Å ωc = 593.6 cm?1, De 0.33 eV) and to involve a triple 3d bond; while the Cr2 potential curve is not bound but shows a shoulder near the experimental Re and the wave function shows multiple 3d bonding in this region. 相似文献
11.
The association of BF3 to organocopper and cuprate reagents increases dramatically their reactivity towards epoxides. The same reagents cleave acetals to afford the product of substitution of one alkoxy group, whereas orthoformates lead to acetals under conditions where no further attack occurs. 相似文献
12.
运用核磁共振技术, 研究了室温离子液体1-丁基-3-甲基咪唑四氟硼酸盐([C4mim][BF4])在重水和氘代氯仿中的聚集行为. 实验结果表明, 随着混合体系中离子液体摩尔分数的增加, 在重水中, 离子液体阳离子上各氢原子的化学位移向低场移动, 且呈现了先急剧变化, 后趋于平缓的变化趋势; 在氘代氯仿中, 离子液体阳离子上H2的化学位移向高场移动, H4和H5以及与氮原子直接相连的甲基和亚甲基上的氢原子的化学位移都向低场移动, 且各氢原子的核磁共振信号发生了变化. 根据质量作用定律及1H NMR化学位移随浓度的变化关系计算了[C4mim][BF4]在重水中的临界聚集浓度和聚集数, 并在离子液体阴、阳离子缔合以及离子液体与溶剂相互作用的基础上对实验结果进行了讨论. 相似文献
13.
Trinath Mishra Christian Schwickert Rainer P?ttgen 《Monatshefte für Chemie / Chemical Monthly》2011,15(2):973-978
Abstract
The intermetallic zinc compounds La3Pd4Zn4 and La3Pt4Zn4 were synthesized by induction melting of the elements in sealed tantalum tubes. The structures were refined from X-ray single-crystal diffractometer data: Gd3Cu4Ge4 type, Immm, a = 1,440.7(5), b = 743.6(2), c = 419.5(2) pm, wR 2 = 0.0511, 353 F 2 for La3Pd4Zn4; and a = 1,439.9(2), b = 748.1(1), c = 415.66(6) pm, wR 2 = 0.0558, 471 F 2 for La3Pt4Zn4 with 23 variables per refinement. The palladium (platinum) and zinc atoms build up a three-dimensional polyanionic [Pd4Zn4] (260–281 pm Pd–Zn) and [Pt4Zn4] (260–279 pm Pt–Zn) network in which the lanthanum atoms fill cavities of CN 14 (6 Pd/Pt + 8 Zn for La1) and CN 12 (6 Pd/Pt + 6 Zn for La2), respectively. The copper position of the Gd3Cu4Ge4 type is occupied by zinc and the two crystallographically independent germanium sites by palladium (platinum), a new coloring pattern for this structure type. Within the [Pd4Zn4] and [Pt4Zn4] the Pd2 and Pt2 atoms form Pd2–Pd2 (291 pm) and Pt2–Pt2 (296 pm) dumbbells. The structures of La3Pd4Zn4 and La3Pt4Zn4 are discussed with respect to the prototype Gd3Cu4Ge4 and the Zintl phase Sr3Li4Sb4. Temperature-dependent magnetic susceptibility measurements indicate diamagnetism for La3Pt4Zn4 and Pauli paramagnetism for La3Pd4Zn4. 相似文献14.
The effect of γ radiation on 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) was investigated in detail. It was found that radiation induced an increase of UV absorption of the ionic liquid but no change in its glass transition point. Raman spectroscopy analysis indicates that the radiolysis of [bmim][BF4] induces detectable destruction of alkyl-chain and scission of H-atoms of ring of imidizolium cation, and the relatively small changes of BF4− anion. Viscosities of irradiated [bmim][BF4] samples were measured at different shear rates and temperatures, and compared with irradiated [bmim][PF6] samples. The plots of shear stress against shear rate indicates that [bmim][BF4] is a Newtonian fluid, no matter with irradiation. The viscosity of irradiated [bmim][BF4] decreased with increasing of temperature and followed an Arrhenius equation. However, radiation caused no change in the viscosity of [bmim][BF4], but a decrease in the viscosity of [bmim][PF6] by up to 10%. We conclude that the radiation stability of [bmim][BF4] is higher than [bmim][PF6]. 相似文献
15.
A. A. Firer S. N. Solov’ev A. Ya. Dupal 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(7):1236-1238
The enthalpies of interaction of (ClOF2)2[MnF6](cr) and ClOF2[BF4](cr) with water and an aqueous solution of alkali and the enthalpies of several auxiliary processes were measured at 298.15
K on an isothermic-shell calorimeter. Based on these and literature data, the standard enthalpies of formation of (ClOF2)2[MnF6](cr) and ClOF2[BF4](cr) at 298.15 K were calculated by two independent methods (−1643 ± 11 and −1368 ± 5 kJ/mol, respectively).
Original Russian Text ? A.A. Firer, S.N. Solov’ev, A.Ya. Dupal, 2009, published in Zhurnal Fizicheskoi Khimii, 2009, Vol.
83, No. 7, pp. 1391–1393. 相似文献
16.
New 4-cyanopyridine halide and mixed-halide Cu4OBr
n
Cl(6−n)(4-CNpy)4 complexes (4-CNpy = 4-cyanopyridine, n = 0–6) were synthesised, characterised, and studied by infrared spectra, electronic spectra, and cyclic voltammetry. Infrared
spectra revealed donor-acceptor vibrational couplings of the Cu4O, Cu-Cl, and Cu-N stretching vibrations with the in-plane and out-of-plane pyridine ring vibrations. The infrared spectra,
electronic spectra, and half-wave potentials correspond to a weak donor and a strong acceptor behaviour of the 4-cyanopyridine
ligands and to π-back bonding, Cu(II)→pyridine rings. The results were compared with the related pyridine and 4-substituted pyridine complexes. 相似文献
17.
Andriy V. Tkachuk 《Journal of solid state chemistry》2004,177(11):3939-3943
The isostructural ternary transition-metal silicides Zr3Mn4Si6 and Hf3Mn4Si6 can be prepared by direct reaction of the elemental components or by arc-melting. The single-crystal structure of Zr3Mn4Si6 was determined by X-ray diffraction (Pearson symbol tP104, tetragonal, space group P42/mbc, Z=8, , ). Zr3Mn4Si6 is isostructural to Nb3Fe3CrSi6 and contains an essentially ordered arrangement of the transition-metal atoms. Square antiprismatic clusters with Zr and Mn atoms at the corners and Si atoms at the center share opposite faces to form one-dimensional columns extending along the c direction. These columns occupy channels that are outlined by a framework of edge- and face-sharing MnSi6 octahedra. The extensive metal-metal interactions in the structure are complemented by Si-Si bonding in the form of dumbbells, linear chains, and zigzag chains. 相似文献
18.
The solubilities of three dibasic carboxylic acids (adipic acid, glutaric acid, and succinic acid) in water, in the ionic liquid of 1-butyl-3-methyl-imidazolim tetrafluoroborate ([Bmim][BF4]), and in the aqueous [Bmim][BF4] solutions have been measured by a solid-disapperance method. The binodal curve of water + [Bmim][BF4] was also determined experimentally from solid–liquid–liquid coexistence temperature up to near the upper critical solution temperature. Experimental results showed that each acid-containing binary behaved as a simple eutectic system. The solid–liquid equilibrium (SLE) data were correlated with the NRTL model for each binary system. The NRTL model with these determined binary parameters predicted the solid-disappearance temperatures of the aqueous ternary mixtures containing [Bmim][BF4] and the dibasic acids to within an average absolute deviation of 2.0%. 相似文献
19.
X-ray diffraction studies on both powdered and single crystal samples of (NF4)2NiF6 have shown that the compound crystallises in a tetragonal form derived from the K2 PtCl6 structure. The space group is I 4/m and the unit cell dimensions are : a = 6.828 (5) Å, c = 9.270 (9) Å, c/a = 1.358, and Z = 2. 相似文献
20.
A Cu(Ⅰ) complex with mix ligands [Cu(HIm)2(PPh3)2](BF4) was synthesized and characterized by elemental analysis, IRspectroscopy and X-ray diffraction crystallography. The crystal belongs to monoclinic system and P21/c space group, with cell parameters, a=1.2836(3)nm, b=1.5089(3)nm, c=2.0661(4)nm, α=90°, β=101.464(4)°,γ=90°, V=3.9219(13)nm3, Z=4 and Dc=1.374mg·m-3. The Cu(Ⅰ) is coordinated by two Patoms from triphenylphosphine and two Natoms from imidazole to form the distorted tetrahedral geometry. 相似文献