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1.
LnCl 3 (Ln=Nd, Gd) reacts with C 5H 9C 5H 4Na (or K 2C 8H 8) in THF (C 5H 9C 5H 4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C 5H 9C 5H 4)LnCl 2(THF) n (orC 8H 8)LnCl 2(THF) n], which further reacts with K 2C 8H 8 (or C 5H 9C 5H 4Na) in THF to form the litle complexes. If Ln=Nd the complex (C 8H 8)Nd(C 5H 9C 5H 4)(THF) 2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C 8H 8)Gd(C %H 9)(THF)][(C 8H 8)Gd(C 5H 9H 4)(THF) 2] (b) was obtained in crystalline form. The crystal structure analysis shows that in (C8H8)Ln(C5H9C5H4)(THF)2 (Ln=Nd or Gd), the Cyclopentylcyclopentadieny (η5), cyclooctatetraenyl (η8) and two oxygen atoms from THF are coordinated to Nd3+ (or Gd3+) with coordination number 10. The centroid of the cyclopentadienyl ring (Cp′) in C5H9C5H4 group, cyclooctatetraenyl centroid (COTL) and two oxygens (THF) form a twisted tetrahedron around Nd3+ (or Gd3+). In (C8H8)Gd(C5H9C5H4)(THF), the cyclopentyl-cyclopentadienyl (η5), cyclooctatetraenyl (η8) and one oxygen atom are coordinated to Gd3+ with the coordination number of 9 and Cp′, COT and oxygen atom form a triangular plane around Gd3+, which is almost in the plane (dev. -0.0144 Å). 相似文献
2.
The complex (di-η 5-C 5H 4CH 2CH 2CH 2C 5H 4)Ti(η 1-C 5H 5) 2 (I) can be obtained unambiguously starting from the corresponding bridged titanocene dichloride. Attempts to synthesize the isomeric compounds (η 5-C 5H 5) 2 Ti(di-η 1-C 5H 4-CH 2CH 2CH 2C 5H 4) (I′) by the action of a convenient bridged dianion on (C 5H 5) 2 TiCl 2 afford several compounds, one of them is the complex I. The possibility of interconversion of these complexes by a fluctional process is discussed. 相似文献
3.
Asymmetric ditertiary stibine sulfides (C 6H 5)(CH 3)(S)SbCH 2Sb(CH 3)(C 6H 5) and [(C 6H 5)(CH 3)(S)Sb] 2(CH 2) 3 have been prepared. It was found that they exist as only one of two possible diastereomers in the crystalline state. However, isomerization to the other form takes place in solution, resulting in an equilibrium mixture. A possibility of configurational lability of tertiary stibine sulfide was suggested for the first time. 相似文献
4.
The crystal and molecular structure of the complex Th[η 5-(CH 3) 5C 5] 2[CH 2-Si(CH 3) 3] 2, which undergoes facile intramolecular cyclometalation to the thoracyclobutane Th[η 5-(CH 3) 5C 5] 2(CH 2) 2Si(CH 3) 2, is reported. While the Th[η 5-(CH 3) 5C 5] 2 ligation is unexceptional, the Th[CH 2Si(CH 3) 3] 2 fragment is highly unsymmetrical having Th-C (corresponding angle Th-C-Si) 2.51(1) Å (132.0(6)°) and 2.46(1) Å (148.0(7)°). This conformation, which appears to result from severe intramolecular non-bonded contacts, allows a methyl hydrogen atom of one CH 2Si(CH 3) 3 ligand to approach within ca. 2.3 Å of the α-carbon atom of the other CH 2Si(CH 3) 3 ligand. 相似文献
5.
MMe 5(dmpe) (M = Nb or Ta, dmpe = Me 2PCH 2CH 2PMe 2) reacts with H 2 (500 atm) and dmpe in THF at 60°C to give MH 5(dmpe) 2? NbH 5(dmpe) 2 readily reacts with two mol of CO or ethylene (L) to give NbHL 2(dmpe) 2. The exchange of the hydride ligand with the ethylene protons in NbH(C 2H 4) 2(dmpe) 2 is not rapid on the 1H NMR time scale (60 MHz) at 95°C. 相似文献
6.
Reduction of (C 5H 5) 2TiCl 2 with Zn in presence of benzyl cyanide gives the (μ-alkyl-ideneamido)titanocene complex [(C 5H 5) 2TiCl] 2[μ-{N=C(CH 2C 6H 5)---C(CH 2C 6H 5)=N}] with C---C bond formation between two benzyl cyanide molecules. X-ray structure investigation indicates a symmetrical structure. The C=N distances are smaller than usual, the Ti---N distances are very short, and the Ti---N---C angle differs only a little from 180°, which infers a heteroallene structure of the complex. 相似文献
7.
The ruthenium(II) complex Ru(CO) 2(NH 2(NH 2CH 2C 6H 5) 2(Si(C 6H 5)(CH 3) 2)I has been prepared by the reaction of Ru(CO) 4(Si(C 6H 5)(CH 3) 2)I with benzylamine. Two-dimensional homonuclear 1H NMR experiments examine the scalar coupling of the enantiotopic amino and methylene protons of the benzylamine ligand. X-ray analysis of Ru(CO) 2(NH 2CH 2C 6H 5) 2(Si(C 6H 5)(CH 3) 2)I·1/3C 5H 12 (triclinic; P
; a = 14.266(4), b = 15.748(5), c = 20.082(6) Å; = 94.38(3), β = 96.30(2), γ = 101.52(2)°) indicates three crystallographically unique complexes form a clathrate with a pentane guest. 相似文献
8.
Reaction of YbI 2 with two equivalents of cyclopentylindenyl lithium (C 5H 9C 9H 6Li) affords ytterbium(II) substituted indenyl complex (C 5H 9C 9H 6) 2Yb(THF) 2 (1) which shows high activity to ring-opening polymerization (ROP) of lactones. The reaction between YbI 2 and cyclopentylcyclopentadienyl sodium (C 5H 9C 5H 4Na) gives complex [(C 5H 9C 5H 4) 2Yb(THF)] 2O 2 (2) in the presence of a trace amount of O 2, the molecular structure of which comprises two (C 5H 9C 5H 4) 2Yb(THF) bridged by an asymmetric O 2 unit. The O 2 unit and ytterbium atoms define a plane that contains a Ci symmetry center. 相似文献
9.
The results of several MC SCF calculations on CH 4, C 2H 4 and C 2H 6 with minimun bases of Slater type AO's are reported. The computing method is a quadratically convergent process. Better final energies are obtained if localized MO's are used. 相似文献
10.
The complex [Ag(DDM) 2(CH 3C 6H 4NH 2)]NO 3, where DDM is 4,4-diaminodiphenylmethane [CH 2(C 6H 4NH 2) 2], was synthesized and its structure was determined. The crystals are monoclinic, space group P2 1/ n, a = 9.543(2) ?, b = 18.056(4) ?, c = 1.901(2) ?, β = 106.94(3)°, V = 1796.8(6) ? 3, ρ calcd = 1.443 g/cm 3, Z = 4. The Ag atom (at the inversion center) is coordinated at the vertices of an almost undistorted octahedron by six nitrogen
atoms of the primary amino groups from four bridging DDM molecules and two terminal p-toluidine molecules (Ag-N, 2.546(3) ?; NAgN, 89.7–90.3°). Wavelike layers composed of conjugate multiunit metal rings, each
containing four Ag + ions and four bridging DDM ligands, are formed in the structure in the [101] direction (a 2D polymer). Uncoordinated NO
3
−
anions are arranged in the cavities between the layers and link them by N-H⋯O hydrogen bonds.
Original Russian Text ? Yu.V. Kokunov, V.V. Kovalev, Yu.E. Gorbunova, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007,
Vol. 52, No. 12, pp. 1992–1998. 相似文献
11.
A new chemical oxidant [N(4-C 6H 4Br) 3][B(C 6F 5) 4], was prepared and used to synthesize [Fe(C 5H 5) 2][B(C 6F 5) 4]. The crystal structure of [Fe(C 5H 5) 2][B(C 6F 5) 4] was determined. 相似文献
12.
The crystal and molecular structure of hexaphenylditin selenide (C 6H 5) 3SnSeSn(G 6H 5) 3 was determined by X-ray diffraction data and was refined to R 0.055. The compound is monoclinic, space group P2 1, with a 9.950(4), b 18.650(7), c 18.066(6) Å, β 106.81(4)°, Z 4. The two molecules in the asymmetric unit differ slightly in their conformations, both having approximate C2 symmetry. Bond lengths and angles are: SnSe 2.526 (2.521(3) ? 2.538(3)) Å; SnC 2.138 (2.107(16)?2.168(19)) Å; SnSeSn 103.4(1)°, 105.2(1)°. There are only slight angular distortions at the SnSeC 3 tetrahedra (SeSnC angles: 104.3(5)?114.8(4)°). The bond data indicate essentially single bonds around the Sn atoms. 相似文献
13.
ortho-Metallation of PhCH 2SMe in a reaciton with MeMn(CO) 5 ahs been confirmed by a single crystal X-ray structural determination of the title complex. 相似文献
14.
en Two differnt crystal modifications of hexaphenyldigermanium sulfide (C 6H 5GeSGe(C 6H 5) 3 (I and II were obtained by crystallization from hot benzene/methanol or form ethanol at 20°C. Single crystal X-ray structural analyses for both I (low temperature data at ?130°C) and II (at 20°C) (I, R = 0.046; II, R = 0.048) were performed. I is monoclinic, P2 1/c, with a = 11.020(3), b = 15.473(3), c 18.606(3) »,π = 106.92(2)°, Z = 4; II is orthorhombic, P2 12 12 1, with a = 2.617(2), b = 17.345(3), c = 18.408(3) », Z = 4.The molecules have different conformeric structures with respect to a rotation of the (C 6H 6) 3Ge groups around the Ge bonds with very similar bond lenghts and angles. Bond data for I(II) are: GeS 2.212(1) and 2.261(1) » (2.227(2) and 2.240(2) »); GeC 1.933(4) ? 1.971(4), mean 1.945(5) » (1.931(7)?1.954(7), mean 1.943(4) »); GeSGe 111.2(1)° (110.7(1)°). The Ge bond lenghts are comparable to those in thiogermanates and do not indicate significant π-bond contributions. 相似文献
15.
The crystal structure of tetrakis(methyldiphenylphosphine)iridium(I) tetrafluoroborate with cyclohexane of solvation, [Ir(PPh 2Me) 4]BF 4·C 6H 12, has been determined from a three-dimensional X-ray analysis. The compound has been analysed in space group C2/c of the monoclinic system. There are twelve molecules (i.e. 1.5 molecules per asymmetric unit) in a cell of dimensions a = 36.804(8), b = 22.93(2), c = 21.676(4) Å, β = 121.41(1)°. Block-diagonal least-squares refinement has given a final R-factor of 0.060 for 7905 reflections having I > 3σ(I).The structure consists of two crystallographically distinct, but structurally similar molecules, one on a general position and one on a crystallographic two-fold axis. The phosphine ligands around the iridium atoms are in a very distorted square-planar arrangement. The reactions of the cation axe discussed in terms of this structure. 相似文献
16.
Heat-capacity measurements have been made in the temperature range 110 to 300 K. In the range 160 to 240 K the chromocene curve shows an anomaly related to an order-disorder phase transition in the solid. On the other hand the dibenzene chromium curve indicates no phase transition and is in accordance with an ordered structure at room temperature. 相似文献
17.
A new silicated cyclotriphosphazene N 3P 3(O 2C 12H 8) 2(OC 6H 4Si(CH 3) 3)(OC 6H 4Br) 1 has been synthesized and characterized. The solid state pyrolysis of 1 in air gives a nanostructured SiP 2O 7 3D network. The morphology of the network strongly depends on the temperature of the pyrolysis. Spinal-like columns and ring-shaped
SiP 2O 7 are formed at 800 °C, while, at 600 °C, fused grains of about 300 nm were observed. Based on air TG and DSC thermal studies,
we propose the mechanism of formation for the nanostructured network. 相似文献
18.
The complex dicarbonylbis(diphenylethylphosphine)platinum, Pt(CO) 2[P(C 6H 5) 2(C 2H 5)] 2, crystallizes in either of the enantiomorphous space groups P3 121 (No. 152) and P3 221 (No. 154) with cell dimensions a = 10.64(1), c = 22.06(1) Å, U = 2163 Å 3; pc = 1.564 g/cm 3 for Z = 3, pm = 1.55(3) g/cm 3. The intensities of 1177 independent reflections have been determined by counter methods with MoKα monochromatized radiation. The structure has been solved by the heavy atom method. The refinement, carried out by full-matrix least squares down to a final R factor of 0.042, has enabled the absolute configuration of the crystal sample (space group P3 121) to be ascertained. The molecule is roughly tetrahedral, and has the metal atom lying on a two-fold axis of the cell. Bond parameters are: PtC = 1.92(2) Å, PtP = 2.360(4) Å, CPtC = 117(1)° and PPtP = 97.9(2)°. The PtC 2 and PtP 2 moieties make a dihedral angle of 86.0(3)°. The overall C2 symmetry of the molecule is probably only a statistically averaged situation, a disorder in the PtCO interactions being apparent from the orientations of the thermal ellipsoids of the C and O atoms. 相似文献
19.
We report a new synthesis and characterization of Ir(C 2H 4) 2(C 5H 7O 2) [(acetylacetonato)-bis(η 2-ethene)iridium(I)], prepared from (NH 4) 3IrCl 6 · H 2O in a yield of about 45%. The compound has been characterized by X-ray diffraction crystallography, infrared, Raman, and NMR spectroscopies and calculations at the level of density functional theory. Ir(C 2H 4) 2(C 5H 7O 2) is isostructural with Rh(C 2H 4) 2(C 5H 7O 2), but there is a substantial difference in the ethylene binding energies, with Ir-ethylene having a stronger interaction than Rh-ethylene; two ethylenes are bound to Ir with a binding energy of 94 kcal/mol and to Rh with a binding energy of 70 kcal/mol. 相似文献
20.
The preparations of Nb(CH 3) 5, Ta(CH 3) 5, and Ta(CH 2C 6H 5) 5 are reported in detail. The M(CH 3) 5 complexes decompose autocatalytically to give 3.4 ± 0.1 mol of methane and a non-hyclrolyzable residue with approximate composition MC 1–5H while Ta(CH 2C 6H 5) 5 decomposes in a non-autocatalytic manner to give ca. 2.6 mol of toluene per Ta. Decomposition of Nb(CD 3) 5 gave 96% CD 4 in diethyl ether while the toluene produced on decomposition of Ta(CD 2C 6H 5) 5 was at least 90%- d3. An observed kinetic deuterium isotope effect of 2–3 in each case is evidence that an α-CH(D) bond is broken in a slow step of the decomposition. It is postulated that M(CH 3) 5 and Ta(CH 2C 6H 5) 5 decompose primarily by α-hydrogen atom abstraction though almost certainly in a complex, possibly intermolecular fashion in the case of M(CH 3) 5. In neither case (R = CH 3 or CH 2C 6H 5) was there evidence for significant homolytic cleavage of the metalcarbon bond to give free alkyl radicals. 相似文献
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