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1.
LnCl3 (Ln=Nd, Gd) reacts with C5H9C5H4Na (or K2C8H8) in THF (C5H9C5H4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C5H9C5H4)LnCl2(THF)n (orC8H8)LnCl2(THF)n], which further reacts with K2C8H8 (or C5H9C5H4Na) in THF to form the litle complexes. If Ln=Nd the complex (C8H8)Nd(C5H9C5H4)(THF)2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C8H8)Gd(C%H9)(THF)][(C8H8)Gd(C5H9H4)(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.
Zwitterionic titanoxanes {Cp[η5-C5H4B(C6F5)3]Ti}2O (I) and {(η5-iPrC5H4)[η5-1,3-iPrC5H3B(C6F5)3]Ti}2O (II), which contain two positively charged Ti(IV) centres in the molecule, are able to catalyse the ring-opening polymerization of -caprolactone (-CL) in toluene solution and in bulk. The process proceeds with a noticeable rate even at room temperature and accelerates strongly on raising the temperature to 60 °C. The best results have been obtained on carrying out the reaction in bulk. Under these conditions, the use of I as a catalyst (-CL:I = 1000:1) gives at 60 °C close to quantitative yield of poly--CL with the molecular mass of 197 000. An increase in the -CL:I ratio to 6000:1 increases the molecular mass of poly--CL to 530 000. Tetrahydrofuran (THF) is also polymerized under the action of I albeit with a lesser rate. However, the molecular mass of the resulting poly-THF can reach rather big values under optimal conditions (up to 217 000 at 20 °C and the THF:I ratio of 770:1). A rise in the reaction temperature from 20 to 60 °C results here to a decrease in the efficiency of the process. Titanoxane II is close to I in its catalytic activity in the -CL polymerization but it is much less active in the polymerization of THF. Propylene oxide (PO), in contrast to -CL and THF, gives with I only liquid oligomers in wide temperature and PO:I molar ratio ranges (−30 to +20 °C, PO:I = 500–2000:1). γ-Butyrolactone and 1-methyl-2-pyrrolidone are not polymerized under the action of I at room temperature. The reactions found are the first examples of catalysis of the cationic ring-opening polymerization by zwitterionic metallocenes of the group IVB metals.  相似文献   

3.
We report a new synthesis and characterization of Ir(C2H4)2(C5H7O2) [(acetylacetonato)-bis(η2-ethene)iridium(I)], prepared from (NH4)3IrCl6 · H2O 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(C2H4)2(C5H7O2) is isostructural with Rh(C2H4)2(C5H7O2), 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   

4.
1-Allyl-4-aminopyridinium chloride reacts with Cu(NO3)2 · 3H2O in an ethanolic solution under the conditions of ac electrochemical synthesis at copper electrodes to form crystals of compound [(NH2C5H4N(C3H5))2Cu3Cl3(NO3)2] (I). The crystals of compound I are monoclinic: space group P21/c, Z = 4, a = 25.770(7), b = 7.230(4), c = 12.505(5) ?, β = 92.58(3)°, V = 2328(2) ?3. The direct interaction of 1-allylquinolinium nitrate with Cu(NO3)2 · 3H2O in a methanolic solution in the presence of metallic copper yields crystals of compound [C9H7N(C3H5)Cu(NO3)2] (II). The crystals of compound II are triclinic: space group P , a = 6.756(3), b = 8.391(4), c = 12.489(5) ?, α = 77.18(3)°, β = 89.48(4)°, γ = 73.32(3)°, V = 662.0(5) ?3. The structure of compound I is built of infinite linear anions: polymeric fragments {(NH2C5H4N(C3H5))2Cu3Cl3(NO3)2} n . Each of two copper atoms (Cu(1) and Cu(2)) π-coordinates the C=C bonds of the allyl groups of the 1-allyl-4-aminopyridinium cations, the oxygen atom of the nitrate ions, and two chlorine atoms. The third copper atom Cu(3) is linearly linked with two chlorine atoms. Particular polymeric fragments are additionally joined by the N-H…O, C-H…O, C-H…Cl hydrogen bonds. The crystal structure of compound II is built-up of the isolated L2Cu2(NO3)4 fragments (L is the 1-allylquinolinium cation). The metal atom is localized in the trigonal pyramidal coordination environment of three oxygen atoms of the nitrate ions and of the C=C bond of the allyl group of the cation. The particular L2Cu2(NO3)4 fragments are additionally joined by the C-H…O hydrogen bonds. Original Russian Text ? A.V. Pavlyuk, T. Lis, M.G. Mys’kiv, 2009, published in Koordinatsionnaya Khimiya, 2009, Vol. 35, No. 6, pp. 458–462.  相似文献   

5.
The complex dicarbonylbis(diphenylethylphosphine)platinum, Pt(CO)2[P(C6H5)2(C2H5)]2, crystallizes in either of the enantiomorphous space groups P3121 (No. 152) and P3221 (No. 154) with cell dimensions a = 10.64(1), c = 22.06(1) Å, U = 2163 Å3; pc = 1.564 g/cm3 for Z = 3, pm = 1.55(3) g/cm3. The intensities of 1177 independent reflections have been determined by counter methods with MoKα 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 P3121) 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: PtC = 1.92(2) Å, PtP = 2.360(4) Å, CPtC = 117(1)° and PPtP = 97.9(2)°. The PtC2 and PtP2 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 PtCO interactions being apparent from the orientations of the thermal ellipsoids of the C and O atoms.  相似文献   

6.
The novel seven-coordinate complex [(n-Bu)2Sn(C10H8N2O3)(C2H5OH)]2 (C10H8N2O32- is the dinegative ion of 2-oxo-propionic acid benzoyl hydrazone) was synthesized by the reaction of (n-Bu)2SnO with 2-oxo-propionic acid benzoyl hydrazone in 1∶1 molar ratio in benzene-ethanol (V/V, 3/1), and its structure was characterized by X-ray single crystal diffraction. The crystal belongs to a tetragonal system with space group I41/a, a=2.4890(2)nm, b=2.4890(2)nm, c=1.5170(3)nm, V=9.398(2)nm3, Z=8, F(000)=3968, Dc=1.366g·cm-3, and the structure was refined to final R1=0.0530, wR2=0.0971. The structure of the title complex is described as a dimer through weak interactions of Sn…O bonding and hydrogen bond. The tin atoms rendered sev-en-coordination in a distorted pentagonal bipyramid geometry structure, four oxygen atoms [O1, O2, O2#1 and O4] and one nitrogen atom N2 formed the equatorial plane and C11-Sn1-C15 is the axis. CCDC: 212696.  相似文献   

7.
The divalent europium bis-fluorenyl complex (C13H9)2Eu(THF)2 was synthesized by the metathesis reaction of EuI2(THF)2 with two equivalents of fluorenylpotassium and by the protolytic substitution of the naphthalene ligand in the (C10H8)Eu(THF)2 complex using the reaction with fluorene. According to X-ray diffraction data, the complex displays a skewed sandwich structure, in which one fluorenyl ligand is η5-coordinated to the metal atom, whereas the η3-coordination mode makes a great contribution to the coordination of another ligand. The (C5Me4H)2YbI(THF) complex was synthesized by the reaction of YbI3(THF)2 with two equivalents of (C5Me4H)K. The structure of the complex was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 530–534, March, 2008.  相似文献   

8.
The crystal structures of the Rh[(EtO)2PS2]3 (I) and Co[(PhO)2PS2]3 (II) chelate compounds were determined from X-ray diffraction (XRD) data (CAD-4 diffractometer, MoK β radiation, 1193 F hkl , R = 0.0516 for I and 513 F hkl , R = 0.0305 for II). Crystals I are monoclinic: a = 14.233(3) Å, b = 13.570(3) Å, c = 14.272(3) Å; β = 90.66(3)°, V = 2756.3(10) Å3, Z = 4, ρcalc = 1.587 g/cm3, space group C2/c. Crystals II are trigonal: a = 15.149(2) Å, c = 30.306(6) Å; V = 6023.2(16) Å3, Z = 6, ρcalc = 1.493 g/cm3, space group R3ˉ. Structures I and II consist of discrete mononuclear molecules. The coordination polyhedra of the M atoms (M = Rh, Co) are distorted octahedra formed by six sulfur atoms of three cyclic bidentate (RO)2 PS2 ligands. Original Russian Text Copyright ? 2008 by R. F. Klevtsova, L. A. Glinskaya, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 2, pp. 330–334, March–April, 2008.  相似文献   

9.
The complex (di-η5-C5H4CH2CH2CH2C5H4)Ti(η1-C5H5)2 (I) can be obtained unambiguously starting from the corresponding bridged titanocene dichloride. Attempts to synthesize the isomeric compounds (η5-C5H5)2 Ti(di-η1-C5H4-CH2CH2CH2C5H4) (I′) by the action of a convenient bridged dianion on (C5H5)2 TiCl2 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   

10.
在无水乙醇中,用吡咯烷二硫代氨基甲酸铵(APDTC)和1,10-邻菲咯啉(o-phen·H2O)与TmCl3·3.65H2O作用,合成了未见文献报道的三元固态配合物,确定它的组成为Tm[(C5/sub>H8NS2)3(C12H8N2)]。 用RD496-Ⅲ微量热计测定了298.15 K下水合氯化铥及两个配体在无水乙醇中的溶解焓,两个配体醇溶液的混合焓及不同温度下标题化合物液相生成反应的焓变。在实验和计算基础上,得到了液相生成反应的热力学参数(活化焓、活化熵和活化自由能),速率常数和动力学参数(表现活化能、频率因子和反应级数)。通过合理的热化学循环,求得了298.15 K时标题化合物的固相生成反应焓变;推导了用该热量计测定固态物质比热容的计算式,并测定了题目配合物298.15 K的比热容。用RBC-Ⅱ精密转动弹热量计测定了题目配合物的恒容燃烧热, 计算了它们的标准摩尔燃烧焓和标准摩尔生成焓。  相似文献   

11.
The product from reaction of lanthanum chloride seven-hydrate with salicylic acid and 8-hydroxyquinoline, La(C7H5O3)2·(C9H6NO), was characterized by IR, elemental analysis, molar conductance, and thermogravimetric analysis. The standard molar enthalpies of solution of [LaCl3·7H2O (s)], [2C7H6O3 (s)], [C9H7NO (s)] and [La(C7H5O3)2·(C9H6NO) (s)] in a mixed solvent of absolute ethyl alcohol, dimethyl formamide (DMF) and perchloric acid were determined by calorimetry to be [LaCl3·7H2O (s), 298.15 K] = −96.45 ± 0.18 kJ mol−1, [2C7H6O3 (s), 298.15 K] = 14.99 ± 0.17 kJ mol−1, [C9H7NO (s), 298.15 K] = −3.86 ± 0.06 kJ mol−1 and [La(C7H5O3)2·(C9H6NO) (s), 298.15 K] = −117.78 ± 0.11 kJ mol−1. The enthalpy change of the reaction
(1)  相似文献   

12.
配位超分子聚合物的设计合成与应用研究一直是配位化学、超分子化学、生物无机化学及材料科学等领域的热点研究课题之一,具有微孔结构的配位聚合物吸引了许多科学家的目光,这不仅因为该类配合物具有新颖的结构,展现出多种诱人的拓扑结构,更主要的 是因为它们在离子交换、催化、磁性材料、光学材料及气体贮存领域的应用潜力[1~3].  相似文献   

13.
The reaction of LuCl3(THF)3 with Na(1,3-Ph2C5H3) followed by the in situ reaction with Na2[Ph4C2] produced (1,3-Ph2C5H3)Lu(Ph4C2)(THF) (1). The structure of 1 was established by X-ray diffraction. In the crystal structure of 1, the bis-allyl η6-coordination of the tetraphenylethylene dianion to the lutetium cation was observed. The structures of (1,3-Ph2C5H3)LuCl2(THF)3 and (C5H5)LuCl2(THF)3 were determined by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1912–1918, October, 2007.  相似文献   

14.
A novel binuclear copper complex of [Cu(C14H8O3)(C9H7N)(C2H5OH)]2 was synthesized and characterized by elemental analysis, IR, thermal analysis and X-ray single crystal diffraction. The title complex crystallizes in monoclinic system, space group P21/c with a=1.381 7(3) nm, b=1.184 3(2) nm, c=1.332 5(3) nm, β=104.77(3)°. Each copper(II) atom is five-coordinated by three oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, one quinoline nitrogen atom and one ethanol oxygen atom, forming a distorted square-pyramidal coordination geometry. Two copper(II) atoms are linked by two 9-hydroxy-fluorene-9-carboxylate ligands into a dimmer structure with the Cu…Cu separation being 0.298 39(8) nm. The dinuclear motifs are further linked into a two-dimensional supramolecular layer via hydrogen bonds interactions. CCDC: 272850.  相似文献   

15.
合成了标题化合物[Mo(C9H6NO)2(O)2](C9H6NO=8-羟基喹啉),测定了化合物的晶体结构.晶体属单斜晶系,空间群Cc,a=13.372(3),b=9.421(2),c=13.554(3)A,β=109.71(3)°,V=1607.6(8)A3.结构由直接法解出,最后可靠性因子R=0.0473,Rw=0.062.Mo原子为6配位,位于八面体的中心.两个配体氧相互处于邻位,分别与8-羟基喹啉中的N原子处于对位.  相似文献   

16.
The bis(μ-dimethylphosphido)dicobalt complex [C5H5Co(μ-PMe2)]2 (II) has been prepared from Co(C5H5 and PMe2H on almost quantitative yield. It has also been made by reduction of [C5H5Co(PMe2H)3]I2 (IV) with NaH and from the reaction of [C5H5(PMe3)Co(μ-CO)2Mn(CO)C5H4Me] with PMe2H. Protonation of II with CF3CO3H in the presence of NH4PF6 produces the PF6? salt of the (μ-hydrido)dicobalt cation [(C5H5Co)2(μ-H)(μ-PMe2)2]+ (V) which reacts with aqueous NaOH to give II. Similar treatment of [C5H5Co(μ-SMe]2 with CF3CO2H/NH4PF6 leads to the formation of [(C5H5Co)2(μ-SMe)3]PF6 (VI). The nucleophilic character of complex II has also been demonstrated in the reaction with SO2, which gives [(C5H5Co)2 (μ-PMe2)2(μ-SO2)] (VII). The crystal and molecular structures of II, the corresponding bis(μ-diphenylphosphido) compound [C5H5Co(μ-PPh2)]2 (III) and the BPh4? salt of V have been determined. In both neutral complexes the Co2P2 cores are similarly puckered, as reflected in the dihedral angle between the CoP2 and P2Co′ planes of 108.1 and 105.0° for R = Me and Ph, respectively. The CoCo bond length and the PP interatomic separations are essentially identical for both dimers. The CoCo bond length in V, 2.517(1) Å, is lower than that in II, 2.542(2) Å. The only obvious structural variation between the unprotonated and the protonated species is the large difference in the degree of canting of the C5H5 rings with respect to each other. The angles between the C5(ring)-centroid and the CoCo line are ca. 150 and 167° in II and V, respectively, which reflects the influence of the bridging hydride ligand in the cationic complex.  相似文献   

17.
The [Cp2HfH2Al(H)Br(OBu)]2 complex (1) was prepared by the reaction of Cp2HfBr2 with AlH3 in THF and characterized by X-ray crystallography. The formation of dinuclear complex 1 proceeds through the intermediate formation (as a result of cleavage of THF molecules) of the >Al(μ-OBu)2Al< fragment. The latter is linked to two hafnocene dihydride molecules by the Hf-H-Al hydrogen bridges. The Hf atom in complex 1 has a 16-electron environment.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2082–2085, October, 2004.  相似文献   

18.
Using an on-line solution-reaction isoperibol calorimeter, the standard molar enthalpies of reaction for the general thermochemical reaction: LnCl3·6H2O(s) + 2C9H7NO(s) + CH3COONa(s) = Ln(C9H6NO)2(C2H3O2)(s) + NaCl(s) + 2HCl(g) + 6H2O(l) (Ln: Nd, Sm), were determined at T=298.15 K, as  kJ mol−l, respectively. From the mentioned standard molar enthalpies of reaction and other auxiliary thermodynamic quantities, the standard molar enthalpies of formation of Ln(C9H6NO)2(C2H3O2)(s) (Ln: Nd, Sm), at T=298.15 K, have been derived to be: −(1494.7±3.3) and −(1501.5±3.4) kJ mol−l, respectively.  相似文献   

19.
In the presence of NBu4nBr acting as phase-transfer reagent, organosilicon trichloride C2H5SiCl3 reacts in acetonitrile with the trivacant tungstophosphate sodium salt β-A-Na8H[PW9O34]·24H2O to give hybrid organosilyl polyoxotungstate derivative α-A-[NBu4n]3[PW9O34(C2H5SiO)3(C2H5Si)]. X-ray single crystal structural analysis indicates that the title compound is monoclinic, space group Cc, with lattice constants a=26.828(5), b=22.459(5), c=17.517(4) Å, β=103.19(3)°, V=10,276(4) Å3, Z=4, R=0.0462. According to the result of X-ray single crystal diffraction and chemical analysis, the hybrid polyanion consists of one α-A-[PW9O34]9− framework on which are grafted simultaneously three RSiO groups through six Si-O-W bridge bonds, each of which is attached to the fourth RSi group through three Si-O-Si bridge bonds. The hybrid polyanion becomes a partial saturated, closed cage structure and also has an assembly of virtual C3V symmetry.  相似文献   

20.
Reduction of (C5H5)2TiCl2 with Zn in presence of benzyl cyanide gives the (μ-alkyl-ideneamido)titanocene complex [(C5H5)2TiCl]2[μ-{N=C(CH2C6H5)---C(CH2C6H5)=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   


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