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The water‐insoluble title compound, catena‐poly­[palladium(II)‐di‐μ‐acetato‐κ4O:O′], [Pd(C2H3O2)2]n, was obtained from a nitratopalladium solution and acetic acid as a pale‐pink powder. Ab initio crystal structure determination was carried out using X‐ray powder diffraction techniques. Patterson and Fourier syntheses were used for atom location and the Rietveld technique was applied for the final structure refinement. The structure consists of palladium acetate complexes connected into polymeric chains running along b, in which two Pd atoms are bridged by two acetate groups that are in a cis configuration with respect to one another. The unique Pd atom lies on a site with 2/m symmetry and the acetate moieties have imposed m symmetry; these are joined into infinite chains running along the b direction. The shortest Pd⋯Pd distance in the row is 2.9192 (1) Å. The planes of adjacent palladium complexes are inclined towards each other, the angle between the planes being approximately 30°.  相似文献   

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The silver-assisted ligand metathesis reaction involving a platinum(II) complex of formula [PtClMe(N,N-chelate)] with acetonitrile has been investigated. By using a suitably hindered N,N-chelate, an otherwise hardly detectable trinuclear species has been isolated and characterized through X-ray diffractometry. The trinuclear cation consists of two nearly orthogonal [PtCl(Me)(N,N-chelate)] square-planar units entrapping an Ag(+) cation through the chloride ligands that, acting as bidentate, form a linear AgCl(2) unit with two nonequivalent Ag-Cl bonds. The residual acidity of the silver cation is satisfied by one secondary Ag-Pt interaction [Ag-Pt(1) = 2.82 A] in which the platinum atom acts as a donor. Kinetic studies have demonstrated that the silver assistance operates both through a simple associative step and through a pathway in which the above trinuclear complex is an active intermediate. In a noncoordinating solvent the latter species evolves with AgCl loss and formation of a dinuclear Pt,Pt complex showing a rare single chloride bridge.  相似文献   

5.
The dimeric iron carbonyl [CpFe(CO)(2)](2) and the iodosilanes tBu(2)RSiI were obtained from the reaction of [CpFe(CO)(2)]I with the silanides Na[SiRtBu(2)] (R = Me, tBu) in THF. By the reactions of [CpFe(CO)(2)]I and Na[SiRtBu(2)] (R = Me, tBu) the disilanes tBu(2)RSiSiRtBu(2) (R = Me, tBu) were additionally formed using more than one equivalent of the silanide. In this context it should be noted that reduction of [CpFe(CO)(2)](2) with Na[SitBu(3)] gives the disilanes tBu(3)SiSitBu(3) along with the sodium ferrate [(Na(18-crown-6))(2)Cp][CpFe(CO)(2)]. The potassium analogue [(K(18-crown-6))(2)Cp][CpFe(CO)(2)] (orthorhombic, space group Pmc2(1)), however, could be isolated as a minor product from the reaction of [CpFe(CO)(2)]I with [K(18-crown-6)][PtBu(2)BH(3)]. The reaction of [CpFe(CO)(2)](2) with the potassium benzophenone ketyl radical and subsequent treatment with 18-crown-6 yielded the ferrate [K(18-crown-6)][CpFe(CO)(2)] in THF at room temperature. The crown ether complex [K(18-crown-6)][CpFe(CO)(2)] was analyzed using X-ray crystallography (orthorhombic, space group Pna2(1)) and its thermal behaviour was investigated.  相似文献   

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Hexakis[bis(2-aminoethoxy)methylsilylethyl]benzene and hexakis[bis(N,N-dimethyl-2-aminoethoxy)methylsilylethyl]benzene C6[(NR2CH2CH2O)2SiMeCH2CH2]6 (4, R = H; 5, R = Me) were prepared from hexakis(methyldichlorosilylethyl)benzene C6(Cl2MeSiCH2CH2)6 and 2-aminoethanol or N,N-dimethyl-2-aminoethanol, respectively. Compounds 4 and 5 react with anhydrous cobalt (ii) chloride to give poorly soluble dodecachloro{hexakis[bis(2-aminoethoxy)methylsilylethyl]benzene}hexacobalt and dodecachloro{hexakis[bis(N,N-dimethyl-2-aminoethoxy)methylsilylethyl]benzene}hexacobalt {Co6[(NR2CH2CH2O)2SiMeCH2CH2]6C6}Cl12 (R = H or Me), respectively. Polyfunctional amine 4 reacts with dicobalt octacarbonyl to produce hexakis[bis(2-aminoethoxy)methylsilylethyl]benzenedicobalt(ii) tetrakis(tetracarbonylcobaltate) {Co2[(NH2CH2CH2O)2SiMeCH2CH2]6C6}[Co(CO)4]4. N,N-Dimethyl-substituted polyfunctional amine 5 is lowly reactive in the reaction with Co2(CO)8, whereas the simplest model of this compound, viz., bis(N,N-dimethyl-2-aminoethoxy)dimethylsilane (NMe2CH2CH2O)2SiMe2, slowly reacts with Co2(CO)8 to give tris[bis(N,N-dimethyl-2-aminoethoxy)dimethylsilane]cobalt(ii) bis(tetracarbonylcobaltate) {Co[(NMe2CH2CH2O)2SiMe2]3}[Co(CO)4]2. Thermal decomposition and transformations of the resulting complexes under the action of oxygen and water were studied.  相似文献   

8.
Combination of 2-aminoethanethiol hydrochloride and HgI2 in water in the presence of a base yielded a cyclic molecular structure, [Hg4I4(SCH2CH2NH2)4] (1). For the same reaction in the absence of the base, a similar structure with protonated amines was expected; however, polymeric [Hg4I8(SCH2CH2NH3)2]n.nH2O2 was formed instead. The structures are quite variable despite similar reaction conditions. For instance, there is an additional Hg-N interaction in 1 due to the use of base. The environment around tetracoordinate Hg in 1 is comprised of S, N, and I atoms, with the ligand forming a five-membered chelate and the I atoms present alternate to each other. In the repeating unit of 2, three independent types of Hg atoms are observed, with HgSI3, HgS2I2, and HgI4 bonding environments that have both bridging and terminal I atoms. A simple mechanistic pathway for the formation of 1 and 2 is proposed that includes the presence of three- and four-coordinate Hg intermediates in the solution. Intermolecular hydrogen bonding involving N, I, and S in 1 and N, I, and O atoms in 2 create extended three-dimensional networks. The shortest Hg... Hg distances are found to be intrachain in the range 3.938-3.962 A and indicate no interaction between these atoms. The solution studies (UV-vis and NMR) along with solid-state (IR, Raman, and X-ray) studies for 1 and 2 confirm retention of the structural configuration in the solution. The thermal study of 2 indicates that degradation of the complex occurs in a single step, in contrast to 1, which takes a more complicated decomposition pathway.  相似文献   

9.
100 MHz 1 H n.m.r. spectra of cis-(CH3)2Pt[P(OCH3)3]2 are analysed in full detail as superimposing [AR3X9]2 and [AR3X9]2M systems. The cis structure is derived from J(PP) and J(PtP).  相似文献   

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《Polyhedron》1999,18(8-9):1107-1113
Structural characterization of [S(CH2CH2pzMe2)2]ZnCl2 by X-ray diffraction demonstrates that the potentially tridentate [NNS] donor ligand S(CH2CH2pzMe2)2 does not coordinate via sulfur, but only binds through the pyrazolyl groups. Furthermore, the ligand does not chelate, but preferentially bridges two zinc centers, thereby resulting in a polymeric, helical, structure. In contrast to the zinc system, the thioether functionality does bind to cadmium in related derivatives, [S(CH2CH2pzMe2)2]CdI2 and [S(CH2CH2pzMe2)2]Cd(NO3)2.  相似文献   

12.
The characteristic feature of the structure of the title compound, dipotassium bis(sulfito‐κS)mercurate(II) 2.25‐hydrate, is a layered arrangement parallel to (001) where each of the two independent [Hg(SO3)2]2− anions are grouped into centrosymmetric pairs and are surrounded by two K+ cations to give the overall layer composition {K2[Hg(SO3)2]2}2−. The remaining cations and the uncoordinated water molecules are situated between these layers. Within the [Hg(SO3)2]2− anions, the central Hg atoms are twofold coordinated by S atoms, with a mean Hg—S bond length of 2.384 (2) Å. The anions are slightly bent [174.26 (3) and 176.99 (3)°] due to intermolecular O...Hg interactions greater than 2.8 Å. All coordination polyhedra around the K+ cations are considerably distorted, with coordination numbers ranging from six to nine. Although the H atoms of the five water molecules (one with symmetry 2) could not be located, O...O separations between 2.80 and 2.95 Å suggest a system of medium to weak O—H...O hydrogen bonds which help to consolidate the structural set‐up. Differences and similarities between the bis(sulfito‐κS)mercurate(II) anions in the title compound and those in the related salts (NH4)2[Hg(SO3)2] and Na2[Hg(SO3)2]·H2O are discussed.  相似文献   

13.
The thermally unstable compound [Hg[P(C(6)F(5))(2)](2)] was obtained from the reaction of mercury cyanide and bis(pentafluorophenyl)phosphane in DMF solution and characterized by multinuclear NMR spectroscopy. The thermally stable trinuclear compounds [Hg[(mu-P(CF(3))(2))W(CO)(5)](2)] and [Hg[(mu-P(C(6)F(5))(2))W(CO)(5)](2)] are isolated and completely characterized. The higher order NMR spectra exhibiting multinuclear satellite systems have been sufficiently analyzed. [Hg[(mu-P(CF(3))(2))W(CO)(5)](2)].2DMF crystallizes in the monoclinic space group C2/c with a = 2366.2(3) pm, b = 1046.9(1) pm, c = 104.0(1) pm, and beta = 104.01(1) degrees. Structural, NMR spectroscopic, and vibrational data prove a weak coordination of the two DMF molecules. Structural, vibrational, and NMR spectroscopic evidence is given for a successive weakening of the pi back-bonding effect of the W-P bond in the order [W(CO)(5)PH(R(f))(2)], [Hg[(mu-P(R(f))(2))W(CO)(5)](2)], and [W[P(R(f))(2)](CO)(5)](-) with R(f) = C(6)F(5) and CF(3). The pi back-bonding effect of the W-C bonds increases vice versa.  相似文献   

14.
Given the nucleophilicity of the [Pt(2)S(2)] ring, the evolution of [Pt(2)(mu-S)(2)(P intersection P)(2)] (P intersection P=1,2-bis(diphenylphosphino)ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp)) metalloligands in the presence of the simplest electrophilic species, the proton, has been studied. Combined use of experimental and theoretical data has allowed the whole set of reactions ensuing the protonation of the [Pt(2)S(2)] core to be established. The titration of [Pt(2)(mu-S)(2)(P intersection P)(2)] with HCl or HClO(4) was monitored mainly by (31)P[(1)H] NMR and mass techniques. Characterization of all the species involved was completed with the determination of the crystal structure of [Pt(SH)(2)(P intersection P)], for dppe and dppp, and [Pt(3)(mu(3)-S)(2)(dppp)(3)](PF(6))(2). The first protonation step of the [Pt(2)S(2)] core leads to the stable [Pt(2)(mu-S)(mu-SH)(P intersection P)(2)](+) complex, but the second step implies disintegration of the ring, thus giving rise to various mononuclear species. The subsequent evolution of some of these species allows regeneration of [Pt(2)(mu-S)(mu-SH)(P intersection P)(2)](+), evidencing the cyclic nature of this process. Whereas the reaction pathway is essentially common for both phosphine ligands, dppe and dppp, the different coordinating ability of Cl(-) or ClO(4) (-) determines the nature of the final products, [PtCl(2)(P intersection P)], [Pt(3)(mu(3)-S)(2)(P intersection P)(3)]Cl(2) or [Pt(3)(mu(3)-S)(2)(P intersection P)(3)](ClO(4))(2). DFT calculations have corroborated the thermodynamic feasibility of the reactions proposed on the basis of experimental data.  相似文献   

15.
无水YCl3与一倍量的LLi(L=2,4 二苯胺基 2 戊烯基)在甲苯 四氢呋喃(THF)中反应,分离得到了双烯酮亚胺稀土二氯化物LYCl2(THF)2,并测定了其晶体结构。配合物属正交晶系,Pna21空间群,晶胞参数为a=1.9612(5)nm,b=0.9582(3)nm,c=1.4203(4)nm,V=2.669(1)nm3,Z=6,Dc=1.377mg·m-3,μ=2.408mm-1(MoKα),F(000)=1144,R=0.0358,wR=0.0640。中心金属钇原子与双烯酮亚胺基上的2个氮原子、2个氯原子以及2个四氢呋喃上的氧原子配位,形成一个六配位的、稍扭曲的八面体几何构型的配合物。  相似文献   

16.
The compositions and structures of two new organic metals based on ET [where ET = bis(ethylenedithio)tetrathiafulvalene], viz., (ET)2[Hg(SCN)Cl2], with a metal-dielectric transition temperature (Tm-d) of 35°K, and (ET)2[Hg(SCN)2Br], with Tm-d = 140°K, were established by x-ray diffraction analysis. The crystal structures of the investigated compounds are similar to the structure of the previously studied organic metal (ET)2[Hg(SCN)2Cl] with Tm-d = 50°K. The principal crystallographic data for (ET)2[Hg(SCN)Cl2] are as follows: a = 36.64(1), b = 8.300(4), c = 11.798(1) Å, = 89.91(3)°, V = 3588.1(9) Å3, space group Cc, Z = 4, dcalc = 2.05 g/cm3. The principal crystallographic data for (ET)2[Hg(SCN)2Br] are as follows: a = 37.088(14), b = 8.338(3), c = 11.738(5) Å, = 89.71(3)°, V = 3629.6(8) Å3, space group C2/c, Z = 8, dcalc = 2.15 g/cm3. A characteristic feature of the crystal structure of the investigated compounds is alternation of the anion and cation layers along the a axis of the crystal. In the cation layer of the k type the ET are interconnected by shortened S...S intermolecular contacts (3.39–3.58 Å). The [Hg(SCN)3–nXn] anions (X = Cl, Br; n = 1, 2) form polymeric chains with one or two bridged SCN groups. A tendency for a decrease in the metal-dielectric transition temperature with a decrease in the volume of the anion is detected in the (ET)2[Hg(SCN)3–nXn] salts, where X = Cl and Br, and n = 1 and 2.Institute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2323–2331, October, 1992.  相似文献   

17.
Reaction of [(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2 with Neopentyllithium: Formation of {[(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2CH2CMe3} ? [Li(TMEDA)2]⊕ The recently synthesized methylene bridged dialuminium compound [(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2 reacts with neopentyl lithium in the presence of TMEDA to give the stable {[(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2CH2 · CMe3}? [Li(TMEDA)2]⊕ decomposing at 115°C. The aluminium atoms therein are not additionally bridged, but the new substituent is occupying a terminal position as detected by crystal structure determination. A compound is formed containing a saturated, fourfold coordinated neighbouring a formally unsaturated, threefold coordinated aluminium atom. Due to high sterical restrictions the Al? C bonds are lengthened up to 209.0(3) pm at the alanate site and the Al? C? Al angle in the methylene bridge is extraordinarily enlarged to 144.4(2)°.  相似文献   

18.
Treatment of tetrakis(triphenylphosphine)platinum with elemental selenium (red or vitreous) in toluene solution under reflux yields an insoluble solid. This dissolves in dichloromethane with reaction, eventually to form a 1 : 1 mixture of [PtCl2(PPh3)2] and the new compound [Pt(Se2CH2)(PPh3)2], which has been characterized by multinuclear NMR spectroscopy and X-ray crystallography. Under the same conditions, tetrakis(triphenylphosphine)-palladium yields only decomposition products. © John Wiley & Sons, Inc.  相似文献   

19.
Polysulfonyl Amines. XXXVII. Preparation of Mercury Dimesylamides. Crystal and Molecular Structures of Hg[N(SO2CH3)2]2, Hg[{N(SO2CH3)2}2(DMSO)2], and Hg[{N(SO2CH3)2}2(HMPA)] Hg[N(SO2CH3)2]2 ( 1 ) and Hg2[N(SO2CH3)2]2 ( 2 a ) are formed as colourless, sparingly soluble precipitates when solutions of Hg(NO3)2 or Hg2(NO3)2 in dilute nitric acid are added to an aqueous HN(SO2CH3)2 solution. By a similar reaction, Hg2[N(SO2C6H4 ? Cl? 4)2]2 is obtained. 1 forms isolable complexes of composition Hg[N(SO2CH3)2]2 · 2 L with L = dimethyl sulfoxide (complex 3 a ), acetonitrile, dimethyl formamide, pyridine or 1,10-phenanthroline and a (1/1) complex Hg[N(SO2CH3)2]2 · HMPA ( 4 ) with hexamethyl phosphoramide. Attempted complexation of 2 a with some of these ligands induced formation of Hg0 and the corresponding HgII complexes. Crystallographic data (at -95°C) are for 1: space group 141/a, a = 990.7(2), c = 2897.7(8) pm, V = 2.844 nm3, Z = 8, Dx = 2.545Mgm?3; for 4a: space group P1 , a = 767.8(2), b = 859.2(2), c = 925.2(2)pm α = 68.44(2), β = 86.68(2), γ = 76.24(2)°, V = 0.551nm3, Z = 1, Dx = 2.113 Mgm?3; for 4: space group P21/c, a = 1041.3(3), b = 1545.4(3), c = 1542.5(3) pm, β = 100.30(2)°, V = 2.474nm3, Z = 4, Dx = 1.944Mgm3. The three compounds form molecular crystals. The molecular structures contain a linear or approximately linear, covalent NHgN moiety; the Hg? N distances and N? Hg? N angles are 206.7(4) pm and 176.3(2)° for 1, 207.2(2) pm and 180.0° for 3a, 205.7(4)/206.7(4) pm and 170.5(1)° for 4. In the complexes 3a and 4, the 0-ligands are bonded to the Hg atoms perpendicularly to the N? Hg? N axes, leading in 3a to a square-planar trans-(N2O2) coordination with Hg? 0 261.2(2) pm and N? Hg? O 92.3(1)/87.7(1)°, in 4 to a slightly distorted T-shaped (N2O) geometry with Hg? 0 246.2(4)pm and N? Hg? 0 96.7(1)/92.0(1)°. In all three structures, the primary coordination is extended to a severely distorted (N2O4) hexacoordination by the appropriate number of secondary, inter- and/or intramolecular Hg…?0 inter-actions (0 atoms from sulfonyl groups, Hg…?O distances in the range 280—300pm). The intramolecular Hg…?O interactions give rise to nearly planar four-membered [HgNSO] rings. The molecule of 1 has a two-fold axis through the bisector of the N? Hg? N angle, the molecule of 3a an inversion center at the Hg atom. The molecule of 4 has no symmetry.  相似文献   

20.
Synthesis and Structure of the Platinum(0) Compounds [(dipb)Pt]2(COD) and (dipb)3Pt2 and of the Cluster Hg6[Pt(dipb)]4 (dipb = (i-Pr)2P(CH2)4P(i-Pr)2) The reduction of (dipb)PtCl2 with Na/Hg yields (dipb)Pt as an intermediate which reacts with the amalgam to form the cluster Hg6[Pt(dipb)]4 ( 3 ) or decomposes to (dipb)3Pt2 ( 2 ) and Pt. In the presence of COD [(dipb)Pt]2(COD) ( 1 ) is obtained. 1 crystallizes monoclinicly in the space group P21/c with a = 1596.1(4), b = 996.5(2), c = 1550.4(3) pm, β = 113.65(2)°, Z = 2. In the dinuclear complex two (dipb)Pt units are bridged by a 1,2-η2-5,6-η2 bonded COD ligand. Whereby the C = C double bonds are lengthened to 145 pm. 2 forms triclinic crystals with the space group P1 and a = 1002.0(2), b = 1635.9(3), c = 868.2(2) pm, α = 94.70(2)°, β = 94.45(2)°, σ = 87.95(1)°, Z = 1. In 2 two (dipb)Pt moieties are connected by a μ-dipb ligand in a centrosymmetrical arrangement. 3 is monoclinic with the space group C2/c and a = 1273.8(3), b = 4869.2(6), c = 1660.2(3) pm, β = 95.16(2)°, Z = 4. The clusters Hg6[Pt(dipb)]4 have the symmetry C2. Central unit is a Hg6 octahedron of which four faces are occupied by Pt(dipb) groups. The bonding in the cluster is discussed on the basis of eight Pt? Hg two center bonds of 267.6 pm and two Pt? Hg? Pt three center bonds with Pt? Hg = 288.0 pm.  相似文献   

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