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1.
IR and NMR data showed that the ionic complex Pd2(CHCC6H5)2(C5H7O2)3(BF3)2BF4 isolated in the reaction Pd(Acac)2 + PA + 5BF3OEt2 (Acac is C5H7O2, PA is phenylacetylene) is an adduct of two complexes, namely, (Acac)PdBF4 and [(PA)2Pd(C3-Acac · BF3)]+(Acac · BF3) (coordinatively unsaturated). On dissolution in deuteroacetone or deuteromethanol, the [(Acac)PdF2BF2Pd(C3-Acac · BF3)(PA)2]+(Acac · BF3) adduct decomposed to Pd(Acac)2, 2BF3 · L (L = (CD3)2CO, CD3OD) and the [L(PA)2Pd(C3-Acac]+BF4 complex.  相似文献   

2.
The thermal dehydration and decomposition of Cd(BF4)2·6H2O were studied by means of DTA, TG, DSC and X-ray diffraction methods and the end products of the thermal decomposition were identified. The results of thermal analysis show that the compound is fused first, then it is dehydrated until Cd(BF4)2·3H2O is obtained, which has not been described in the literature so far. The enthalpy of phase transition is H ph.tr.=115.6 kJ mol–1 Separation of the compound is difficult since it is highly hygroscopic. Then, dehydration and decomposition take place simultaneously until CdF2 is obtained which is proved by X-ray diffraction. On further increasing the temperature, CdF2 is oxidized to CdO and the characteristic curve assumes a linear character.Based on TG data, kinetic analyses were carried out separately for both parts of the curve: first until formation of the trihydrate and then — until formation of CdF2. The formal kinetic parameters are as follows:for the first phase:E *=45.3 kJ mol–1; rate equationF=2/3; correlation coefficient 0.9858 for the second phase:E *=230.1 kJ mol–1; rate equationF=(1–)2/3[1-(1–)1/3]–1; correlation coefficient 0.9982.  相似文献   

3.
Crystal structures of [Co(MH)2(Thio)2][BF4] · H2O (I) and [Co(DH)2(NH3)2][BF4] (II), where MH is H3C–C(NOH)–C(NO)–H and DH is H3C–C(NOH)–C(NO)–CH3, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N4S2 for I and N6 for II. In the crystals of I and II, the complex cations and the outer-sphere [BF4] anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.  相似文献   

4.
In the covalently linked 2D coordination network {[Fe(bbtr)(3)](BF(4))(2)}(∞), bbtr = 1,4-di(1,2,3-triazol-1-yl)butane, the iron(II) centers stay in the high-spin (HS) state down to 10 K. They can, however, be quantitatively converted to the low-spin (LS) state by irradiating into the near-IR spin allowed (5)dd band and back again by irradiating into the visible (1)dd band. The compound shows true light-induced bistability below 100 K, thus, having the potential for persistent bidirectional optical switching at elevated temperatures.  相似文献   

5.
Sub-micron-sized [Fe(Htrz)(2)(trz)](BF(4))·H(2)O nanoparticles that exhibit a spin crossover transition are positioned between Au electrodes with sub-100 nm separation. After voltage poling, samples exhibit unexpected large conductivity, with photoconductance and photovoltaic behavior.  相似文献   

6.
The structure of the title compound features mononuclear octahedral CoII cations, trans-[Co(H2O)2(MeCN)4]2+, and trinuclear anions, trans-[Co(H2O)2(MeCN)2(CoCl4)2]2–; the latter centrosymmetric units contain a central octahedral Co(H2O)2(MeCN)2 moiety with two tetrahedral [CoCl4]2– ligands. These two large ions are held in a network of intra- and inter-molecular hydrogen bonding.  相似文献   

7.
[Pt22-S)2(PPh3)4] functions effectively as a bridging bidentate ligand towards Ag+ to form [Ag2Pt43-S)4(PPh3)8]2+. A single crystal X-ray crystallographic anaylsis of the BF4 salt has demonstrated that both Ag+ ions are linearly coordinated to the sulphur atoms, but the small bite angle of the [Pt2(μ-S)2(PPh3)4] ligand leads to an Ag…Ag contact distance of only 2.815(4) Å.  相似文献   

8.
9.
The reaction of MoO2(acac)2 and dibenzylphosphinic acid in ethanol leads to a red distorted cubic tetrameric cluster, Mo4(??3-O)4(??2-O2P(CH2C6H5)2)4O4, and a pink open mixed-valent cluster, Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6, when the reduction is carried out at 120 and 75 °C, respectively. 95Mo NMR spectroscopy revealed a singlet for Mo4(??3-O)4(??2-O2P(CH2C6H5)2)4O4 (1) at 584.9 ppm (????1/2 = 4500 Hz) and two resonances for Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6 (2) at 238.8 ppm (????1/2 = 1250 Hz) and 6.4 ppm (????1/2 = 5999 Hz), which were assigned to the Mo(V) and Mo(VI) sites, respectively. DFT geometries and 95Mo DFT-GIAO chemical shifts for Mo4(??3-O)4(??2-O2P(CH3)2)4O4 (3) and Mo4(??3-O)2(??2-O2P(CH3)2)6O6 (4) are consistent with X-ray crystallography and 95Mo NMR of 1 and 2. The open complex, Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6·2(CH2Cl2), exhibits a central Mo(V)?CMo(V) single bond at 2.6217(5) Å with each Mo(V) atom bonded to one oxo (trans-disposed) terminal ligand.  相似文献   

10.
11.
The organoantimony peroxide (Ar2SbO)4(O2)2 (Ar = C6H3OMe-2, Br-5) was synthesized by the oxidation of Ar3Sb with hydrogen peroxide in the presence or acetoxime or acetophenone oxime in dioxane. The product crystallizes with various content of the solvent molecules in the crystal unit cell [1.5 (I) and 6 (II), respectively]. An X-ray diffraction analysis of the solvates was performed. Four antimony atoms in the peroxide are in the octahedral coordination, and are linked through bridging oxygen atoms and two peroxide groups. The distances Sb-C, Sb-Obridge, Sb-Operoxide, O-O and Sb...Sb are 2.117–2.122, 1.960–1.972, 2.193–2.235, 1.461, 1.465 and 3.223–3.237 Å in I, and 2.112, 2.119, 1.957, 1,966, 2.204, 2,246, 1,467, and 3.2439 Å in II.  相似文献   

12.
The title compound reacted rapidly with CN(t)Bu at room temperature by displacing the BF(4)(-) ligand and incorporating three molecules of isocyanide to yield the electron-precise complex [Mo(2)Cp(2)(μ-PPh(2))(2)(CN(t)Bu)(3)(CO)](BF(4))(2), which was obtained as a mixture of cis and trans isomers. Reaction with several HER(n) molecules (HER(n) = HSPh, HSePh, H(2)PCy) took place with formal elimination of HBF(4) and spontaneous carbonylation to give the electron-precise cations [Mo(2)Cp(2)(μ-ER(n))(μ-PPh(2))(2)(CO)(2)](+). Reactions with several bidentate ligands (L(2)H) having acidic E-H bonds (2-hydroxypyridine, 2-mercaptopyridine, cathecol, 2-aminophenol, and 2-aminothiophenol) proceeded analogously with deprotonation of these bonds with the preference E = S > O > N. The N,O-donor ligands yielded 32-electron chelate derivatives of the type [Mo(2)Cp(2)(O,N-L(2))(μ-PPh(2))(2)(CO)]BF(4) (L(2) = OC(5)H(4)N, OC(6)H(4)NH(2)), whereas the S,N-donors yielded 34-electron, S-bridged complexes [Mo(2)Cp(2)(μ-S:S,N-L(2))(μ-PPh(2))(2)(CO)]BF(4) [L(2) = SC(5)H(4)N (Mo-Mo = 2.8895(8) ?), SC(6)H(4)NH(2)]. However, reaction with catechol gave a monodentate derivative [Mo(2)Cp(2)(O-OC(6)H(4)OH)(μ-PPh(2))(2)(CO)]BF(4). In contrast, reactions of the title complex with several carboxylic acids and related species (acetic, benzoic, and thioacetic acids, acetamide, thioacetamide, and sodium diethyldithiocarbamate) were insensitive to the nature of the donor atoms and gave in all cases 32-electron chelate derivatives of type [Mo(2)Cp(2)(κ(2)-L(2))(μ-PPh(2))(2)(CO)]BF(4). All of the above cations having Mo-bound OH, NH, or NH(2) groups were easily deprotonated upon reaction with 1,8-diazabicycloundec-7-ene (DBU) or other bases to give neutral complexes which exhibited different coordination motifs depending on the donor atoms, including chelate complexes of the type [Mo(2)Cp(2)(κ(2)-L(2)')(μ-PPh(2))(2)(CO)] (L(2)' = OC(6)H(4)O, OC(6)H(4)NH), the bridged complexes [Mo(2)Cp(2)(μ-S,N:S,N-SC(6)H(4)NH)(μ-PPh(2))(2)] and [Mo(2)Cp(2){μ-S,N-N(S)CMe}(μ-PPh(2))(2)], and the terminal acetylimido complex [Mo(2)Cp(2){N-N(O)CMe}(μ-PPh(2))(2)(CO)].  相似文献   

13.
14.
The title complex of copper(Ⅱ) with m-chlorobenzoic acid, 1,10-phenanthroline (phen) and copper perchlorate has been synthesized and characterized in the solvent mixture of water and methanol. Crystal data for this complex: triclinic, space group P, a = 1.06853(12), b = 1.30740(16), c = 1.49546(17) nm, α = 101.791(2), β = 103.413(2), γ = 105.815(2)o, V = 1.8736(4) nm3, Mr = 904.67, Dc = 1.604 g/cm3, Z = 2, F(000) = 924, μ = 1.34 mm-1, GOOF = 1.049, the final R = 0.0324 and wR = 0.0797. The structure analysis shows that a chair-like structure [Cu4O4] is defined by three quadrilaterals shaped by four copper and four oxygen atoms, and every copper ion is coordinated by three oxygen atoms from three water molecules and two nitrogen atoms from one 1,10-phenanthroline molecule, giving a distorted square-pyramidal coordination geometry. The CV analysis results indicate that the electron transfer in the electrode reaction is quasi-reversible.  相似文献   

15.
采用MPW1PW91和BP86 2种密度泛函方法对中性单核锇羰基化合物Os(BF)(CO)n(n=4,3)及双核锇羰基化合物Os2(BF)2(CO)n(n=7,6,5,4)进行理论计算研究,优化得到22个低能异构体.研究发现,单核配位饱和Os(BF)(CO)4的能量最低的异构体对称性为C2v,其BF基团在三角双锥赤道面上.该异构体失去1个赤道面上的CO可得到Os(BF)(CO)3的能量最低异构体.单核Os(BF)(CO)n(n=4,3)的能量最低异构体的BF基团都位于配体三角双锥及缺顶点结构的赤道面上.配位饱和双核Os2(BF)2(CO)7有4个能量接近的异构体,其中能量最低的异构体结构中含有2个呈蝶形的桥配位BF基团.配位不饱和的Os2(BF)2(CO)6的2个能量接近的异构体结构相似,2个桥配位BF基团与2个Os原子构成平行四边形结构单元.配位不饱和的Os2(BF)2(CO)5和Os2(BF)2(CO)4的能量最低异构体都含有由2个桥配位BF基团与2个Os原子构成的平行四边形结构单元.双核Os2(BF)2(CO)n(n=7,6,5,4)能量最低异构体的BF基团都以桥配位形式和Os原子相连.离解能研究表明,单核配位饱和的Os(BF)(CO)4具有一定的热力学稳定性.双核的Os2(BF)2(CO)n(n=7,6)失去1个CO或者分裂为单核的Os(BF)(CO)4或Os(BF)(CO)3所需能量较高,表明其具有一定的热力学稳定性.  相似文献   

16.
The molecular and crystal structure of the title complex (I) obtained by addition of tin fluoride in a hydrofluoric acid solution to 18-crown-6 in methanol was investigated by X-ray structure analysis. The crystals are monoclinic, space group P21/n, a = 13.497(3), b = 7.806(2), c = 9.892(2) Å, β = 95.57(3)°, Z = 2 for C12H32F4O10Sn. In the polymer chain, the crown ether molecules alternate with the inorganic complexes [trans-SnF4(H2O)2] and are linked to them by O-H...O type hydrogen bonds involving the intermediate water molecules. The weak C-H...F interactions bind the chains into the layers which are parallel to the xz plane.  相似文献   

17.
The title compound has been synthesized under solvothermal conditions by reacting vanadium(V) oxytriisopropoxide with terephthalic acid in N,N-dimethylformamide. A combination of synchrotron powder diffraction, infrared spectroscopy, scanning and transmission electron microscopy, and thermal and chemical analysis elucidated the chemical, structural and microstructural features of a new 2D layered inorganic-organic framework. Due to the low-crystallinity of the final material, its crystal structure has been solved from synchrotron X-ray powder diffraction data using a direct space global optimization technique and subsequent constraint Rietveld refinement. [V(4)O(4)(OH)(2)(O(2)CC(6)H(4)CO(2))(4)]·DMF crystallizes in the monoclinic system (space group P2/m (No. 10)); cell parameters: a = 20.923(4) ?, b = 5.963(4) ?, c = 20.425(1) ?, β = 123.70(6)°, V = 2120.1(9) ?(3), Z = 2. The overall structure can be described as an array of parallel 2D layers running along [-101] direction, consisting of two types of vanadium oxidation states and coordination polyhedra: face-shared trigonal prisms (V(4+)) and distorted corner-shared square pyramids (V(5+)). Both configurations form independent parallel chains oriented along the 2-fold symmetry crystallographic b-axis mutually interlinked with terephthalate ligands in a monodentate mode perpendicular to it. The morphology of the compound exhibits long nanofibers, with the growth direction along the layered [-101] axis. The magnetic susceptibility measurements show that the magnetic properties of [V(4)O(4)(OH)(2)(O(2)CC(6)H(4)CO(2))(4)]·DMF can be described by a linear antiferromagnetic chain model, with the isotropic exchange interaction of J = -75 K between the nearest V(4+) neighbours of S = 1/2.  相似文献   

18.
《Polyhedron》1988,7(6):443-448
The salts [Re(CR)CO)25-C9H7)][BF4] [R = C6H4Me-4 or C6H3Me-2,6; η5- C9H7 = indenyl] have been prepared and used to synthesize the dimetal compounds [FeRe(μ-CR)(μ-NO)(CO)45-C9H7)]. The iron-rhenium species containing a bridging p- tolylmethylidyne ligands react with [Fe2(CO)9] or with [Ru(CO)4(η-C2H4)], respectively, to yield the trimetal compounds ([FeMRe(μ3-CC6H4Me-4)(μ-CO)(μ-NO)(CO)65-C9H7)] (M = Fe or Ru).  相似文献   

19.
Two new title compounds have been prepared in powder form. Their spectral data are found to be consistent with the structure foundin Hofmann-Td-type clathrates.  相似文献   

20.
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