首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 531 毫秒
1.
The effects of cyclopentadienyl ring size on the geometry of bimetallic organosamarium complexes have been studied by comparing the X-ray crystal structure of [(C5H4Me)2(THF)Sm(μ-Cl)]2, prepared from KC5H4Me and SmCl3 in THF, with C5Me5 analogs. The complex crystallizes from THF at −30°C in space group Pbcn with a = 20.312(5), b = 9.626(2), c = 16.225(3) Å, V = 3172.5(12) Å3 and Dcalc = 1.74 g cm−3 for Z = 4. Least-squares refinement of the model based on 1759 reflections [|Fo| > 2.0σ(|Fo|)] converged to a final RF = 5.0%. The complex adopts a geometry which has a molecular two-fold rotation axis perpendicular to the Sm2Cl2 plane and a crystallographic inversion center. Hence, both methyl groups of each (C5H4Me)2Sm unit are located on the side opposite of the THF ligands, which are trans to each other, and the four C5H4Me ring centroids define a square plane. The Sm---Cl distances are 2.759(3) and 2.819(3) Å.  相似文献   

2.
The adducts of O2 and SO2 with trans-MeOIr(CO)(PPh3)2 are formed in equilibria and have been characterized. Reaction of the SO2 adduct, Ir(OMe)(SO2)(CO)(PPh3)2 with dioxygen leads to the sulfato complex, Ir(Ome)(CO)(PPh3)2(SO4), the structure of which has been determined. Ir(Ome)(CO)(PPh3)2(SO4) crystallizes in the monoclinic system with a 11.958(2), b 14.163(3), c 12.231(2) Å, β 118.365(12)°, V 1822.7(6) Å3 and Z = 2. Diffraction data for 2θ = 4.5–45.0° (Mo-K) were collected with a Syntex P21 diffractometer and the structure was solved (assuming space group P21/m and an unpleasant 2-fold disordered model) and refined to R = 4.8% for all 2512 independent data (R = 3.5% for those 2042 data with ¦FO¦ > 6σ(¦F¦)). The iridium(III) atom has a distorted octahedral coordination sphere with trans PPh3 ligands and a cis-chelating bidentate O,O′-SO4 group; the structure is completed by mutually cis OMe and CO ligands.  相似文献   

3.
The interaction between Mo2(O2CCH3)4, Me3SiI and I2 in THF resulted in oxygen abstraction from the solvent and formation of [Mo2(μ-O)(μ-I)(μ-O2CCH3) I2(THF)4]+[MoOI4(THF)] and I---(CH2)4---I. The molybdenum complex has been characterized by X-ray diffractometry. Crystal data: triclinic, space group P , a = 13.827(3) Å; b = 15.803(7) Å; c = 9.950(3) Å; = 93.34(4)°; β = 102.40(2)°; γ = 90.09(2)°; V = 2120(2) Å3; Z = 2; dcalc = 2.559 g cm−3; R = 0.0476 (Rw = 0.0613) for 370 parameters and 3938 data with F02> 3σ(F02). The metal-metal distance in the cation is 2.527(2) Å and indicates a strong interaction. The magnetic behavior is consistent with the assignment of one unpaired electron to the Mo27+ core of the cation and one to the d1 Mo(V) center of the anion. The interaction between Mo(CO)6 and I2 in THF also results in the formation of 1,4-diiodobutane.  相似文献   

4.
The methylene-bridged, mixed-chalogen compounds Fe2(CO)6(μ-SeCH2Te) (1) and Fe2(CO)6(μ-SCH2Te) (3) have been synthesised from the room temperature reaction of diazomethane with Fe2(CO)6(μ-SeTe) and Fe2(CO)6(μ-STe), respectively. Compounds 1 and 3 have been characterised by IR, 1H, 13C, 77Se and 125Te NMR spectroscopy. The structure of 1 has been elucidated by X-ray crystallography. The crystalsare monoclinic,space group P21/n, A = 6.695(2), B = 13.993(5), C = 14.007(4)Å, β = 103.03(2)°, V = 1278(7) Å3, Z = 4, Dc = 2.599 g cm−3 and R = 0.030 (Rw = 0.047).  相似文献   

5.
(C5H5)2Lu(μ-Cl2)Na(dme)2 reacts with LiSi(CH3)3 in dimethoxyethane with formation of [Li(dme)3][(C5H5)2Lu(Si(CH3)3)2]. The crystal structure study shows the compound to consist of discrete ions [Li(dme)3]+ and [(C5H5)2Lu(Si(CH3)3)2]. The compound crystallizes in the space group P2/n with a 14.497(5) b 9.041(2), c 14.672(6) Å, β 103.85(3)° and V 1867(2) Å3. The crystal and molecular structure was refined to R = 0.0473 for 2491 observed reflections with Fo 3σ(Fo).  相似文献   

6.
The complex Fe(η6-C5H5CMe3)2 crystallizes in the centrosymmetric triclinic space group P (Ci1; No. 2) with unit cell dimensions of a 8.770(1) Å, b 8.878(1) Å, c 11.991(1) Å, 107.56(1)°, β 90.85(1)°, γ 90.13(1)°, V 890.0(2) Å3 and Z = 2. A full sphere of data was collected on a four-circle diffractometer. The structure was solved and refined to R 7.93% for all 3155 independent reflections and R 4.98% for those 2002 data with | F0 | > 6σ. | F0 |. The molecules lie on crystallographic inversion centers at 0, 0, 0 and 1/2, 0, 1/2; the crystallographic asymmetric unit therefore consists of two independent half molecules. The molecule centered at 0, 0, 0 (molecule “A”) is ordered and well-defined; that centered on 1/2, 0, 1/2 (molecule “B”)is probably disordered, as indicated by larger “thermal parameters” and a greater range of apparent interatomic distances. Discussion em phasizes the geometry of molecule A, which has precise Ci symmetry with Fe(1A)-B(1A) 2.297(4) Å and Fe(1A)-C(ring) distances ranging from 2.057(6) Å to 2.138(4) Å.  相似文献   

7.
Irradiation of the 30-electron Mo25-C5Me5)2(CO)4 and Re2(CO)10 in toluene solution (containing H2O) afforded (in 1–2% yields) a novel triangular metal cluster, (η5-C5Me5)3Mo3(CO)42-H)(η3-O) (1), which was characterized by a single-crystal X-ray diffraction study. Compound 1, of pseudo Cs-m symmetry, has a triangulo-Mo33-O) core with composite Mo---H---Mo and Mo---Mo electron-pair bonds along one unusually short edge (2.660(1) Å) and Mo--- electron-pair bonds along the other two edges (2.916(1) and 2.917(1) Å). The edge-bridged hydride ligand, which displays a characteristic high-field proton NMR resonance at δ −17.79 ppm, was not found from the crystallographic determination but was located via a quantitative potential-energy-minimization method. This procedure unambiguously established that the optimized hydrogen position, which corresponds to a distinct coordination site with identical Mo---H distances of 1.85 Å, is the only one that can be sterically occupied by a metal-bound hydride ligand. This 46-electron species is the first electron-deficient trimolybdenum cluster containing a monoprotonated Mo---Mo double bond; its existence is attributed to ligand overcrowding due to the bulky pentamethylcyclopentadienyl rings. Black (η5- C5Me5)3Mo3(CO)42-H)(η3-O) · 1/2THF crystallizes with two formula species in a triclinic unit cell of P1 symmetry with a 8.603(4), b 11.115(4), c 19.412(11) Å, 80.69(4)°, β 101.10(4)°, and γ 98.88(3)° at −40° C. Least-squares refinement (RAELS with 221 variables) of one independent Mo3 molecule and a centrosymmetrically-disordered THF molecule converged at R1(F) 5.62%, R2(F 6.88% for 8460 independent diffractometry data (I0 ρ 3σ(I0 collected at −40° C with Mo-K radiation  相似文献   

8.
Synthesis, structure, spectroscopy and thermal properties of complex [Co(NCS)2(hmt)2(H2O)2][Co(NCS)2(H2O)4] (H2O) (I), assembled by hexamethylenetetramine and octahedral Co(II) metal ions, are reported. Crystal data for I: Fw 387.34, a=9.020(8), b=12.887(9), c=7.95(1) Å, =96.73(4), β=115.36(5), γ=94.16(4)°, V=820(1) Å3, Z=2, space group=P−1, T=173 K, λ(Mo-K)=0.71070 Å, ρcalc=1.718567 g cm−3, μ=17.44 cm−1, R=0.088, Rw=0.148. An interesting two-dimensional network is assembled via hydrogen bonds through coordinated and free water molecules. The d–d transition energy levels of Co(II) ion are determined by UV–vis spectroscopy and calculated by ligand field theory. The calculated results agree well with experiment ones.  相似文献   

9.
The XeOSeF5+ cation has been synthesized for the first time and characterized in solution by 19F, 77Se and 129Xe NMR spectroscopy and in the solid state by X-ray crystallography and Raman spectroscopy with AsF6 as its counter anion. The X-ray crystal structures of the tellurium analogue and of the Xe(OChF5)2 derivatives have also been determined: [XeOChF5][AsF6] crystallize in tetragonal systems, P4/n, a=6.1356(1) Å, c=13.8232(2) Å, V=520.383(14) Å3, Z=2 and R1=0.0453 at −60°C (Te) and a=6.1195(7) Å, c=13.0315(2) Å, V=488.01(8) Å3, Z=2 and R1=0.0730 at −113°C (Se); Xe(OTeF5)2 crystallizes in a monoclinic system, P21/c, a=10.289(2) Å, b=9.605(2) Å, c=10.478(2) Å, β=106.599(4)°, V=992.3(3) Å3, Z=4 and R1=0.0680 at −127°C; Xe(OSeF5)2 crystallizes in a triclinic system, , a=8.3859(6) Å, c=12.0355(13) Å, V=732.98(11) Å3, Z=3 and R1=0.0504 at −45°C. The energy minimized geometries and vibrational frequencies of the XeOChF5+ cations and Xe(OChF5)2 were calculated using density functional theory, allowing for definitive assignments of their experimental vibrational spectra.  相似文献   

10.
The bimetallic [Pt(NH3)4]2[W(CN)8][NO3]·2H2O is characterised by single-crystal X-ray diffraction [S.G.P21/m(11), a=8.0418(7), b=19.122(2), c=9.0812(6) Å, Z=2]. All platinum centres have the square-plane D4h geometry with average dimensions Pt(1)–N 2.042(2) and Pt(2)–N 2.037(10) Å. The octacyanotungstate anion has the square-antiprismatic D4d configuration with average dimensions W(1)–C 2.164(13), C–N 1.140(12), W(1)–N 3.303(5) Å. The structure exhibits two different mutual orientations of Pt versus W units resulting in Pt(2)–W(1), W(1)* separations of 4.77(2), 4.55(2)* and Pt(1)–W(1) of 6.331(8) Å. A centrosymmetric structure reveals groups of two distinct columns: the first is formed by intercalated NO3 between parallel [Pt(1)(NH3)4]2+ planes and the second consists of [W(CN)8]3− interlayered by, parallel to square faces of W-antiprisms, [Pt(2)(NH3)4]2+. The structure is stabilised through a three-dimensional hydrogen bond network via nitrogen atoms of cyanide ligands, hydrogen atoms of NH3 ligands, water molecules and oxygen atoms of NO3 counteranions. The vibrational pattern and the range of ν(CN) frequencies attributable to the electronic environment of W(V) and W(IV) are consistent with the ground state Pt(II)↔W(V) charge transfer.  相似文献   

11.
One-dimensional Co(dien)2(VO3)3·(H2O) was prepared from the hydrothermal reaction of NH4VO3, Co2O3, diethylenetriamine (dien) and H2O at 130 °C. The compound crystallizes in the monoclinic system, space group P21/c with a=16.1581(6) Å, b=8.7006(3) Å, c=13.9893(4) Å, β=103.1483(11)°, V=1915.13(11) Å3, Z=4, and R1=0.0268 for 3060 observed reflections. Single crystal X-ray diffraction revealed that the structure is composed of infinite one-dimensional chains formed by corner-sharing VO4 tetrahedra with Co(dien)3+ complex cations and crystallization water molecules occupying the interchain positions, which are held together to a three-dimensional network via extensive hydrogen-bonding interactions. The compound, with a new zig-zag conformation of metavanadate chains, is the first example of vanadium oxides incorporating trivalent transition metal coordination groups. Other characterizations by elemental analysis, IR and thermal analysis are also described.  相似文献   

12.
The compound [Zn(H2O)4]2[H2As6V15O42(H2O)]·2H2O (1) has been synthesized and characterized by elemental analysis, IR, ESR, magnetic measurement, third-order nonlinear property study and single crystal X-ray diffraction analysis. The compound 1 crystallizes in trigonal space group R3, a=b=12.0601(17) Å, c=33.970(7) Å, γ=120°, V=4278.8(12) Å3, Z=3 and R1(wR2)=0.0512 (0.1171). The crystal structure is constructed from [H2As6V15O42(H2O)]4− anions and [Zn(H2O)4]2+ cations linked through hydrogen bonds into a network. The [H2As6V15O42(H2O)]6− cluster consists of 15 VO5 square pyramids linked by three As2O5 handle-like units.  相似文献   

13.
Reaction of the optically active primary amine (S)-(—)--methylbenzylamine with trimethylaluminium in heptane affords the crystalline organoaluminium dimer (S)-(—)-(S)-(—)-[(C6H5)CH(CH3)NHA1(CH3)2]2. Isolated as large, colourless, extremely air-sensitive prismatic crystals, the title compound crystallizes in the orthorhombic space group P212121 with unit cell parameters a = 8.406(3), b = 15.505(4), c = 17.547(5) Å, V = 2287 Å3 and p = 1.03 g cm−3 for Z = 4. Least-squares refinement based on 1477 observed reflections converged at R = 0.056, Rw = 0.058. Methane was eliminated during the course of the reaction due to cleavage of A1---C and N---H bonds resulting in an asymmetric A12N2 fragment at the core of the organoaluminium dimer. The mean A1---C bond distance in the dimethylaluminium units is 1.930(8), while the mean A1---N bond distance is 1.950(5) Å. Specific rotation ([]D25 in CH2C12)of the dimer is determined to be - 20.6°.  相似文献   

14.
Naphthaleneytterbium, C10H8Yb(THF)3, reacts with Cp2Cr, Cp2Co, Cp2Ni, and Cp2V in THF to give Cp2Yb. In the case of the reaction of C10H8Yb(THF)3 with Cp2V, vanadium-containing intermediates could be isolated. One of them, CpVC10H8VCp, has been characterized by X-ray diffraction. The crystals are monoclinic, space group P21/n, with a 907.0(5), b 798.8(3), c 1080.8(5) pm, β 105.21(4)°; Z = 2. The structure was refined to R = 0.0288 for 1131 observed reflections (Fo > 4σ(Fo)).  相似文献   

15.
A transition metal-substituted silylacetylene [(η5-C5H5)Fe(CO)2SiMe2C]2, [FpMe2SiC]2 (I) was synthesized and characterized spectroscopically and structurally. I crystallized in the monoclinic space group P21/n, A = 13.011(3) Å B = 12.912(3) Å, C = 13.175(5) Å, β = 94.95(2). The acetylene linkage is reactive toward Co2(CO)8 to form I. Co2(CO)6 (II) which was also characterized spectroscopically and by single crystal X-ray diffraction. II crystallized in the orthorhombic space group Pbca, A = 17.64(2) Å, B = 14.225(10) Å, C = 24.49(2) Å.  相似文献   

16.
Microdifferential thermal analysis (μ-DTA), X-ray diffraction (XRD) and infrared (IR) spectroscopy were used for the first time to investigate the liquidus and solidus relations in the KPO3–Y(PO3)3 system. The only compound observed within the system was KY(PO3)4 melting incongruently at 1033 K. An eutectic appears at 13.5 mol% Y(PO3)3 at 935 K, the peritectic occurs at 1033 K and the phase transition for potassium polyphosphate KPO3 was observed at 725 K. Three monoclinic allotropic phases of the single crystals were obtained. KY(PO3)4 polyphosphate has the P21 space group with lattice parameters: a=7.183(4) Å, b=8.351(6) Å, c=7.983(3) Å, β=91.75(3)° and Z=2 is isostructural with KNd(PO3)4. The second allotropic form of KY(PO3)4 belongs to the P21/n space group with lattice parameters: a=10.835(3) Å, b=9.003(2) Å, c=10.314(1) Å, β=106.09(7)° and Z=4 and is isostructural with TlNd(PO3)4. The IR absorption spectra of the two forms show a chain polyphosphates structure. The last modification of KYP4O12 crystallizes in the C2/c space group with lattice parameters: a=7.825(3) Å, b=12.537(4) Å, c=10.584(2) Å, β=110.22(7)° and Z=4 is isostructural with RbNdP4O12 and contains cyclic anions. The methods of chemical preparations, the determination of crystallographic data and IR spectra for these compounds are reported.  相似文献   

17.
The crystal structure of [WCl4(OPPh3)2](1), formed in the photochemical reaction of W(CO)6 with SnCl4 in the presence of triphenylphosphine, has been determined by the single-crystal X-ray diffraction method. The compound crystallizes in the monoclinic space C2/c, with A=14.027(3), B=13.163(3), C=19.621(4) Å, β=96.36(3)°, Z=4. The structure solved by heavy-atom methods has been refined to R=0.0466, for 3489 observed reflections.

The [WCl4(OPPh3)2] molecule possesses a crystallographically imposed C2 axis passing through the tungsten atom. Despite steric demands, a mutually cis arrangement of triphenylphosphine oxide oxygens is found for [WCl4(OPPh3)2], while there is a slight lengthening of the W---Cl bonds trans to the oxygen atoms.  相似文献   


18.
A new tellurium-containing heterocyclic compound, 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C6H16OSi2Te) (1), has been prepared by treatment of 1,3-bis(chloromethyl)-1,1,3,3-tetramethyldisiloxane with sodium telluride. Mononuclear and dinuclear palladium complexes of this telluride have been prepared by the reaction of 1 with PdCl2(PhCN)2 and Na2PdCl4, respectively. The following new derivatives of 1 have also been produced: C6H16OSi2TeI2 (2), C6H16OSi2TeBr2, C6H16OSi2TeCl2, C6H16OSi2Te(CH3)I, and C6H16OSi2Te(CH2Ph)Br. IR, 1H and 13C NMR and mass spectral data of these new compounds are reported and discussed. 1H NMR studies revealed that in CDCl3 solution both telluronium salts reductively eliminate alkyl halide. The crystal structure of compound 2 has been determined by X-ray diffraction. The compound crystallizes in the monoclinic space group, P21/c, with four molecules in a unit cell of dimension a 12.960(3), b 8.846(2), c 13.754(4) Å, β 92.44(2)°, R = 0.049, and Rw = 0.067 for 3599 unique reflections with |F0| > 3σ(F0). The compound forms a six-membered ring of a slightly displaced boat type. The geometry about the Te atom is pseudo-octahedral, with two carbon atoms (Te-C = 2.156(7) and 2.137(6) Å) and two iodine atoms of the neighbouring molecules (weak intermolecular bonds, Te · I = 3.769 and 3.806 Å) in the equatorial positions and two iodine atoms (Te-I = 2.909(1) and 2.913(1) Å) in the axial positions.  相似文献   

19.
The syntheses and structural determination of NdIII and ErIII complexes with nitrilotriacetic acid (nta) were reported in this paper. Their crystal and molecular structures and compositions were determined by single-crystal X-ray structure analyses and elemental analyses, respectively. The crystal of K3[NdIII(nta)2(H2O)]·6H2O complex belongs to monoclinic crystal system and C2/c space group. The crystal data are as follows: a=1.5490(11) nm, b=1.3028(9) nm, c=2.6237(18) nm, β=96.803(10)°, V=5.257(6) nm3, Z=8, M=763.89, Dc=1.930 g cm−3, μ=2.535 mm−1 and F(000)=3048. The final R1 and wR1 are 0.0390 and 0.0703 for 4501 (I>2σ(I)) unique reflections, R2 and wR2 are 0.0758 and 0.0783 for all 10474 reflections, respectively. The NdIIIN2O7 part in the [NdIII(nta)2(H2O)]3− complex anion has a pseudo-monocapped square antiprismatic nine-coordinate structure in which the eight coordinate atoms (two N and six O) are from the two nta ligands and a water molecule coordinate to the central NdIII ion directly. The crystal of the K3[ErIII(nta)2(H2O)]·5H2O complex also belongs to monoclinic crystal system and C2/c space group. The crystal data are as follows: a=1.5343(5) nm, b=1.2880(4) nm, c=2.6154(8) nm, b=96.033(5)°, V=5.140(3) nm3, Z=8, M=768.89, Dc=1.987 g cm−3, μ=3.833 mm−1 and F(000)=3032. The final R1 and wR1 are 0.0321 and 0.0671 for 4445 (I>2σ(I)) unique reflections, R2 and wR2 are 0.0432 and 0.0699 for all 10207 reflections, respectively. The ErIIIN2O7 part in the [ErIII(nta)2(H2O)]3− complex anion has the same structure as NdIIIN2O7 part in which the eight coordinate atoms (two N and six O) are from the two nta ligands and a water molecule coordinate to the central NdIII ion directly.  相似文献   

20.
The reaction of Ru(CO)4(C2H4) or Ru(CO)5 with 1,5-Ph4P2N4S2 in CH2Cl2/hexane at 23°C produces the dimer [Ru(CO)2(Ph4 P2N4S2)]2 (2), which was shown by X-ray crystallography to have a centrosymmetric structure in which the P2N4S2 ring is attached to one ruthenium atom through two (geminal) nitrogen atoms and the remote sulfur atom and serves as a bridge to the other ruthenium atom via the second sulfur atom. Crystals of 2 ·2(CH2Cl2) are triclinic, space group P (No. 2), a = 12.901(1) Å, b = 13.072(1) Å, c = 10.123(1) Å, = 100.88(1)°, β = 98.90(1)°, γ = 67.50(1)°, V = 1542.4(3) Å, Z = 1 with final R and Rw values of 0.040 and 0.027, respectively.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号