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1.
Toluene solutions of M 2(NMe 2) 6 (M = Mo, W) react with mesitylene selenol (Ar′SeH) to give M 2(SeAr′) 6 complexes. MO 2(OR) 6 (R = tBu, CH 2tBu) react with excess> 6 fold) Ar′SeH to give Mo 2 (SeAr′) 6, whilst W 2(OR) 6(py) 2 (R = iPr, CH 2tBu) react with excess (> 6 fold) Ar′SeH to give W 2(OR) 2(SeAr′) 4. Reaction of MO 2(OPr i) 6 with Ar′SeH produces Mo 2(OPr i) 2 (SeAr′) 4 which crystallizes in two different space groups. These areneselenato complexes are air-stable and insoluble in common organic solvents. X-ray crystallographic studies revealed that the Mo 2(SeAr′) 6 and W 2(SeAr′) 6 compounds are isostructural in the solid state and adopt ethane-like staggered configurations with the following important structural parameters, M---M (W---W/Mo---Mo) 2.3000(11)/2.2175(13) Å, M---Se 2.430 (av.)/2.440 (av.) Å, M---M---SE 97.0° (av.)°. In the solid state W 2(O iPr) 2(SeAr′) 4 adopts the anti-configuration with crystallographically imposed Ci symmetry and W---W 2.3077(7) Å, W---Se 2.435 (av.) Å, W---O 1.858(6) Å; W---W---SE 100.27(3)°, 93.8(3)° and W---W---O 108.41(17)°. Mo 2(OPr i) 2(SeAr′) 4 crystallizes in both P
and A2/ a space groups in which the molecules are isostructural with each other and the tungsten analogue. Important bond lengths and angles are Mo---Mo 2.180(24) Å, Mo---Se 2.432(av.) Å, Mo---O 1.872(9) Å, Mo---Mo---Se 99.39(9)°, 94.71(8)°, Mo---Mo---O 107.55(28)°. 相似文献
2.
An X-ray crystal structure determination for the bimetallic complex Mn 2(CO) 8-[P(NMe 2) 3] 2 reveals that the P(NMe 2) 3 ligands are trans to the Mn---Mn bond and the Mn---Mn bond distance is relatively long, 2.946(1) Å. 相似文献
3.
The reaction between metallic barium and fluoroisopropanol or alcoholysis of [Ba(OPr i) 2] produces a pentanuclear fluoroalkoxide. Its X-ray structure determination showed its formulation to correspond to Ba 5(μ 5-OH)[μ 3-OCH(CF 3) 2] 4[μ 2-OCH(CF 3) 2] 4 [OCH(CF 3) 2](THF) 4(H 2O)·THF. The metallic core is based on a square pyramid encapsulating an hydroxo ligand. In addition to the barium---alkoxide bonds [2.53(3)–2.86(3) Å] neutral O-donors, four THF [2.82(2)–2.86(3) Å] and one H 2O [2.79(3) Å] and secondary barium---fluorine interactions [2.99(2)–3.31(2) Å] ensure high coordination numbers, from 9 to 11 for the metal centers. Hydrogen bonding between the apical fluoroisopropoxide, the water molecule and one THF molecule, non-bonded to a metal center, accounts for the stability of the hydrate and illustrates the Lewis acidity of fluoroalkoxides. Thermal decomposition leads to BaF 2. 相似文献
4.
The reaction between RMgCl (two equivalents) and 1,2-W 2Cl 2(NMe 2) 4 in hydrocarbon solvents affords the compounds W 2R 2(NMe 2) 4, where R = allyl and 1− and 2-methyl-allyl. In the solid state the molecular structure of W 2(C 3H 5) 2(NMe 2) 4 has C2 symmetry with bridging allyl ligands and terminal W---NMe 2 ligands. The W---W distance 2.480(1) Å and the C---C distances, 1.47(1) Å, imply an extensive mixing of the allyl π-MOs with the WW π-MOs, and this is supported by an MO calculation on the molecule W 2(C 3H 5) 2(NH 2) 4 employing the method of Fenske and Hall. The most notable interaction is the ability of the (WW) 6+ centre to donate to the allyl π *-MO (π 3). This interaction is largely responsible for the long W---W distance, as well as the long C---C distances, in the allyl ligand. The structure of the 2-methyl-allyl derivative W 2(C 4H 7) 2(NMe 2) 4 in the solid state reveals a gauche-W 2C 2N 4 core with W---W = 2.286(1) Å and W---C = 2.18(1) Å, typical of WW and W---C triple and single bonds, respectively. In solution (toluene-d 8) 1H and 13C NMR spectra over a temperature range −80°C to +60°C indicate that both anti- and gauche- W 2C 2N 4 rotamers are present for the 2-methyl-allyl derivative. In addition, there is a facile fluxional process that equilibrates both ends of the 2-methyl-allyl ligand on the NMR time-scale. This process leads to a coalescence at 100°C and is believed to take place via an η 3-bound intermediate. The 1-methyl-allyl derivative also binds in an η 1 fashion in solution and temperature-dependent rotations about the W---N, W---C and C=C bonds are frozen out at low temperatures. The spectra of the allyl compound W 2(C 3H 5) 2(NMe 2) 4 revealed the presence of two isomers in solution—one of which can be readily reconciled with the presence of the bridging isomer found in the solid state while the other is proposed to be W 2(η 3-C 3H 5) 2(NMe 2) 4. The compound W 2R 2(NMe 2) 4 where R = 2,4-dimethyl- pentadiene was similarly prepared and displayed dynamic NMR behaviour explainable in terms of facile η 1 = η 3 interconversions. 相似文献
5.
The Hg(II) complex [Hg(TFP) 2(OTFP) 3][ClO 4] 2 with TFP=tri-2-furyl-phosphine and OTFP=tri-2-furylphosphinoxide has been prepared and characterised. It crystallises in the hexagonal P6 3/ m space group with Z=2, a=13.308(3), c=21.092 (4) Å, V=3235(1) Å 3. The structure of the complex cation consists of independent molecules with Hg pentacoordinated in exact trigonal bipyramidal geometry. 相似文献
6.
Polymerizations of ethylene have been carried out by using Cp 2*Zr(NMe 2) 2 (Cp *=C 5Me 5) compound combined with common alkyl aluminums (AlR 3) and methylaluminoxane (MAO) as cocatalysts. The AlMe 3 cocatalyzed system showed no activity due to the formation of stable but inactive heterodinuclear [Cp 2*2Zr(μ-Me) 2AlMe 2] + cations; however, the bulkier AlR 3 [AlEt 3, Al( i-Bu) 3 and Al( i-Bu) 2H] cocatalyzed systems showed very high activities. Especially, Cp 2*Zr(NMe 2) 2/Al( i-Bu) 3 catalyst showed higher catalytic activity and produced higher molecular weight (MW) polymer than Cp 2*Zr(NMe 2) 2/MAO catalyst, demonstrating both MAO and bulky AlR 3 are effective cocatalysts for Cp 2*Zr(NMe 2) 2 compound. 相似文献
7.
The reaction of Pt(PPh 3) n ( n = 3 or 4) with [(CF 3) 3Ge] 2Hg or (CF 3) 3GeHgPt(PPh 3) 2Ge(CF 3) 3 (I) gives a stable diplatinum complex [(CF 3) 3GePt(PPh 3) 2] 2Hg (II). X-Ray analysis has established that compound II contains a Ge---Pt---Hg---Pt---Ge chain of C2 symmetry. Both of the Pt atoms have distorted square-planar coordinations. The bond lengths are: Pt---Hg, 2.630(2) and 2.665(2) Å; Ge---Pt, 2.410(4) and 2.407(4) Å. Compound II reacts with dihydrogen in THF solution under mild conditions to give mercury and the hydride (CF3)3GePt(PPh3)2H. On interaction of II with R2Hg organomercurials (R = Cl, Et, GeEt3, Ge(CF3)3, Ge(C6F5)3) an unknown reaction takes place: Pt(PPh3)2 moieties migrate from the polymetallic grouping into the substrate with the formation of the corresponding RHgPt(PPh3)2R complexes or their demercuration products, R2Pt(PPh3);, (R = Cl, Et). The latter react further with complex I formed in the first step of the process to give Hg and (CF3)3GePt(PPh3)2R. The reaction schemes are discussed. 相似文献
8.
Estertn compounds, (MeO 2CCH 2CH 2) 2SnX 2 [X 2 = I 2 (2); X 2 = Br 2 (9); X 2 = Cl, Br (4)) or X 2 = (NCS) 2 (3)] have been obtained by halide exchange reactions of (MeO 2CCH 2CH 2) 2SnCl 2. Crystal structure determinations of 2–4 revealed chelating MeO 2CCH 2CH 2 units with distorted octahedral geometries at tin. The Sn---O bond lengths in the isothiocyanato complex, 3, are shorter [2.390(11) to 2.498(12), mean 2.439 Å], with the chelate bite angles, C---Sn---O, larger [74.3(7) to 78.2(6), mean 76.0°] than those in the halide analogues 2 and 4 [Sn---O = 2.519(2) to 2.541(8), mean 2.530 Å; C---Sn---O 72.8(3) to 73.9(4), mean 73.3°]. 1H, 13C and 119Sn NMR and IR spectra of 2–4 and 9 were determined in CDCl 3 solution: the NMR spectra of (MeO 2CCH 2CH 2) 2SnX 2 show the following trends: (i) both δ 1H and δ 13C , increase and (ii) both 2J (Sn---H) and 1J( Sn--- C) decrease in the sequence X 2 = (NCS) 2, Cl 2, ClBr, Br 2 and I 2. The MeO 2CCH 2CH 2 and dmio groups (dmio = 1,3-dithiole-2-one-4,5-dithiolato) are all chelating groups in (MeO 2CCH 2CH 2) 2Sn(dmio) (5). As shown by X-ray crystallography, the tin atom in the anion of solid [Q][MeO 2CCH 2CH 2Sn(dmio) 2] 6 (Q = NEt 4) forms 5 strong bonds [to C and the 4 thiolato S atoms, Sn---S 2.459(2) to 2.559(2) Å], arranged in a near trigonal bipyramidal array. There is an additional Intramolecular but weaker, interaction with the carbonyl oxygen atom [Sn---O = 3.111(5) Å]; v(C=O) = 1714 cm −1 in solid 6 (Q = NEt 4). NMR spectra of 5 and 6 are also reported. 相似文献
9.
The compound [Zn(H 2O) 4] 2[H 2As 6V 15O 42(H 2O)]·2H 2O (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) Å 3, Z=3 and R1( wR2)=0.0512 (0.1171). The crystal structure is constructed from [H 2As 6V 15O 42(H 2O)] 4− anions and [Zn(H 2O) 4] 2+ cations linked through hydrogen bonds into a network. The [H 2As 6V 15O 42(H 2O)] 6− cluster consists of 15 VO 5 square pyramids linked by three As 2O 5 handle-like units. 相似文献
10.
The bimetallic [Pt(NH 3) 4] 2[W(CN) 8][NO 3]·2H 2O is characterised by single-crystal X-ray diffraction [S.G. P2 1/ 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 NO 3− between parallel [Pt(1)(NH 3) 4] 2+ planes and the second consists of [W(CN) 8] 3− interlayered by, parallel to square faces of W-antiprisms, [Pt(2)(NH 3) 4] 2+. The structure is stabilised through a three-dimensional hydrogen bond network via nitrogen atoms of cyanide ligands, hydrogen atoms of NH 3 ligands, water molecules and oxygen atoms of NO 3− 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.
Addition of BiBr 3 to Mes 3Bi (Mes = 2, 4, 6-Me 3C 6H 2) in Et 2O gives 86% of Mes 2BiBr (1) as yellow crystals. Reaction of 1 with Ph 2PS 2NH 4 in a 1 : 1 molar ratio gives a quantitative yield of MesBi(S 2PPh 2) 2 (2) rather than the expected dimesitylbismuth compound. The crystal and molecular structures of 1 and 2 were determined at 153 K and 173 K, respectively. They contain Mes 2BiBr molecules with trigonal pyramidal coordination around Bi. The mean Bi---C bond distance is 2.27 Å and the Bi---Br bond distance is 2.690(2) Å. The angles around Bi vary between 89.4 and 106.4°. Intermolecular Bi…Br contacts of 3.795 Å, indicating weak secondary bonding, give rise to zig-zag shaped (Bi---Br) x chains. In the polymeric chain the coordination geometry around bismuth atoms can be described as pseudo-trigonal bipyramidal. The crystals of 2 consist of discrete monomeric MesBi(S 2PPh 2) 2 molecules with a symmetry plane containing the metal atom and the aromatic ring of the attached mesityl group. The dithiophosphinato ligands exhibit an anisobidentate coordination pattern with long and short phosphorus—sulfur bonds, i.e. P(1)---S(1) 2.051(31) Å and P(1)---S(2) 1.980(3) Å, related to short and long bismuth—sulfur distances, respectively, i.e. Bi---S(1) 2.662(2) Å and Bi---S(2) 3.123(3) Å. This leads to a square-pyramidal geometry around the bismuth atom, with the metal lying 0.33 Å above the basal plane formed by the four sulfur atoms. 相似文献
12.
The direct reaction between [TiCl 4(THF) 2] and SnCl 2 in tetrahydrofuran (THF) yields the green paramagnetic salt [ trans-TiCl 2(THF) 4][SnCl 5(THF)]. The same compound is also formed in the reaction between [TiCl 3(THF) 3] and SnCl 4 in THF. Crystals of the title compound are monoclinic with a = 8.442(4), b = 21.589(9), c = 9.262(5) Å, β = 107.91(5)°, Z = 2, space group P2 1/ m. Both metal ions are in an octahedral environment. The titanium atom in the cation [TiCl 2(THF) 4] + lies on the symmetry centre. The tin atom in [SnCl 5(THF)] − is located on the mirror plane. 相似文献
13.
The interaction between Mo 2(O 2CCH 3) 4, Me 3SiI and I 2 in THF resulted in oxygen abstraction from the solvent and formation of [Mo 2(μ-O)(μ-I)(μ-O 2CCH 3) I 2(THF) 4] +[MoOI 4(THF)] − and I---(CH 2) 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) Å 3; 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 Mo 27+ core of the cation and one to the d1 Mo(V) center of the anion. The interaction between Mo(CO) 6 and I 2 in THF also results in the formation of 1,4-diiodobutane. 相似文献
14.
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
15.
The effects of cyclopentadienyl ring size on the geometry of bimetallic organosamarium complexes have been studied by comparing the X-ray crystal structure of [(C 5H 4Me) 2(THF)Sm(μ-Cl)] 2, prepared from KC 5H 4Me and SmCl 3 in THF, with C 5Me 5 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) Å 3 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 Sm 2Cl 2 plane and a crystallographic inversion center. Hence, both methyl groups of each (C 5H 4Me) 2Sm unit are located on the side opposite of the THF ligands, which are trans to each other, and the four C 5H 4Me ring centroids define a square plane. The Sm---Cl distances are 2.759(3) and 2.819(3) Å. 相似文献
16.
Reaction of ansa-cyclopentadienyl pyrrolyl ligand (C 5H 5)CH 2(2-C 4H 3NH) (2) with Ti(NMe 2) 4 affords bis(dimethylamido)titanium complex [(η 5-C 5H 4)CH 2(2-C 4H 3N)]Ti(NMe 2) 2 (3) via amine elimination. A cyclopentadiene ligand with two pendant pyrrolyl arms, a mixture of 1,3- and 1,4-{CH 2(2-C 4H 3NH)} 2C 5H 4 (4), undergoes an analogous reaction with Ti(NMe 2) 4 to give [1,3-{CH 2(2-C 4H 3N)} 2(η 5-C 5H 3)]Ti(NMe 2) (5). Molecular structures of 3 and 5 have been determined by single crystal X-ray diffraction studies. 相似文献
17.
Synthesis, structure, spectroscopy and thermal properties of complex [Co(NCS) 2(hmt) 2(H 2O) 2][Co(NCS) 2(H 2O) 4] (H 2O) (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) Å 3, 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
18.
Reaction of [18]aneS 6 with two molar equivalents of [Cu(NCMe) 4](ClO 4) in CH 2Cl 2-MeCN affords the binuclear copper(I) complex [Cu 2([18]aneS 6)(NCMe) 2](ClO 4) 2. The single crystal X-ray structure of the complex shows a centrosymmetric cation with two tetrahedral copper(I) centres each coordinated to three thioether S-donors of [18]aneS 6,Cu---S(1) = 2.3200(15), Cu---S(4) = 2.3415(16), Cu---S(7) = 2.3250(15) Å, and to one MeCN molecule, Cu---N(1) = 1.939(5) Å, to give an overall NS 3-donation at the metal centres. Additionally, S(7′) shows a long-range interaction, Cu …S(7′) = 3.318(2) Å thus distorting the coordination geometry of the metal ion towards trigonal bipyramidal. The metal-metal separation of 4.428(2) Å suggests that there is no significant interaction between the copper centres of the dimer. Reaction of [9]aneS 3 with one molar equivalent of [Cu(NCMe) 4](ClO 4) in refluxing MeCN in the presence of ligands, L, affords the adducts [Cu([9]aneS 3)L] + (L = PPh 3, AsPh 3). The single crystal X-ray structure of the complex [Cu([9]aneS 3)(AsPh 3)](ClO 4) shows tetrahedral AsS 3 coordination at copper(I) with [9]aneS 3 bound facially to the metal centre, Cu---S = 2.303(6), Cu---As = 2.322(4) Å. 相似文献
19.
A transition metal-substituted silylacetylene [(η 5-C 5H 5)Fe(CO) 2SiMe 2C] 2, [FpMe 2SiC] 2 (I) was synthesized and characterized spectroscopically and structurally. I crystallized in the monoclinic space group P2 1/ 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 Co 2(CO) 8 to form I. Co 2(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
20.
Reaction of the optically active primary amine (S)-(—)--methylbenzylamine with trimethylaluminium in heptane affords the crystalline organoaluminium dimer (S)-(—)-(S)-(—)-[(C 6H 5)CH(CH 3)NHA1(CH 3) 2] 2. Isolated as large, colourless, extremely air-sensitive prismatic crystals, the title compound crystallizes in the orthorhombic space group P2 12 12 1 with unit cell parameters a = 8.406(3), b = 15.505(4), c = 17.547(5) Å, V = 2287 Å 3 and p = 1.03 g cm −3 for Z = 4. Least-squares refinement based on 1477 observed reflections converged at R = 0.056, R w = 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 A1 2N 2 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 CH 2C1 2)of the dimer is determined to be - 20.6°. 相似文献
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