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1.
Chloride abstraction from [{M(η3 --- C3H5)Cl}n] (M = Pt, n = 4 or M = Pd, n = 2) by (NBu4)2[cis-Pt(C6F5)2(CCSiMe3)2] (1) gives rise to novel homo- and hetero-dinuclear zwitterionic derivatives (NBu4) [{cis-Pt(C6F5)2(CCSiMe3)2}M(η3-C3H5)] (M = Pt 2; M = Pd 3) which are formed by a M(η3-allyl)+ unit attached to both alkynyl ligands of the {cis-Pt(C6F5)2(CCSiMe3)2}2− fragment. The structure of 3 has been established by X-ray diffraction. 相似文献
2.
Wolfgang Petz Florian
xler Bernhard Neumüller 《Journal of organometallic chemistry》2009,694(25):4094-4099
The cationic complexes [({Ph3P}2C)Ag(C{PPh3}2)]X (2+, X = Cl, BF4) with a linear arrangement of the ligands were obtained from the reaction of C(PPh3)2 (1) with the appropriate AgX in THF. The 31P NMR spectrum of the cation 2+ exhibits a doublet with J(Ag,P) = 15.3 Hz. The cation was also formed when the adduct O2C ← 1 was allowed to react with AgX in CH2Cl2 in the first step as shown by 31P NMR; however, deprotonation of the solvent finally produced the cation (HC{PPh3}2)+, (H1)+ quantitatively. In the absence of coordinating anions, the tricationic complex [({Ph3P}2CH)Ag(CH{PPh3}2)](BF4)3 (3), containing the cation (H1)+ as ligand, could be isolated by reacting AgBF4 with the salt (H1)(BF4). All compounds were characterized by IR and 31P NMR spectroscopy; the structures of the compounds [2]Cl·1.25THF, 3·5CH2Cl2, 3·4C2H4Cl2, and (H1)(BF4) could be established by X-ray analyses. 相似文献
3.
Chien-Hong Chen Yi-Chieh Ho Gene-Hsiang Lee 《Journal of organometallic chemistry》2009,694(21):3395-3400
The reaction of [Fe(μ-I)(NO)2]2 and TMEDA in a 1:2 molar ratio in THF affords the neutral five-coordinate DNIC [(TMEDA)Fe(NO)2I] (1). The single-crystal X-ray structure shows that the geometry of iron center of complex 1 is best described as a distorted trigonal bipyramidal with two nitrosyl groups positioned in the equatorial plane. The EPR spectrum of complex 1 displays the six-line signal with g = 2.031 (aI = 37.6 G) at 298 K. The coincident g values of EPR among complex 1, protein-bound DNICs and low-molecular-weight DNICs implicate that the five-coordinate DNICs may exist in biological system. The interconversion between complex 1 and [(TMEDA)Fe(NO)2] (2) reveals that the {Fe(NO)2}9 DNICs containing [amine, amine] ligation mode could be stabilized by the five-coordinated geometry while the {Fe(NO)2}10 DNICs containing [amine, amine] ligation mode favors the four coordination sphere. In addition, the transformation from complex 1 to [Fe(NO)2(C3H3N2)]4 (3), [Fe(μ-SPh)(NO)2]2 (4), [PPh4][(PhS)2Fe(NO)2] (5) and [Na-18-crown-6-ether][(C3H3N2)2Fe(NO)2] (6), respectively, in the presence of thiolates or imidazolates indicates that complex 1 could be employed as the precursor for the syntheses of the DNICs containing the [N,N]/[N,S]/[S,S] different ligations. 相似文献
4.
Jian Liu Jia-Ning Xu Ya-Bing Liu Yu-Kun Lu Jiang-Feng Song Xiao Zhang Xiao-Bing Cui Ji-Qing Xu Tie-Gang Wang 《Journal of solid state chemistry》2007,180(12):3456-3462
A novel polyoxometalate [Cu(phen)2]3{PW4VIW5VV3IVO40(VIVO)3[Cu(en)2]}4H2O 1 (en=ethylenediamine, phen=1,10-phenanthroline) has been synthesized hydrothermally and characterized by elemental analysis, IR, XPS, TG, EPR and single-crystal X-ray diffraction analysis. The crystal structure analysis shows that compound 1 contains a novel highly reduced tri-capped and mono-supported pseudo-Keggin-type heteropolyanion, {PW4VIW5VV3IVO40(VIVO)3[Cu(en)2]}6−, three [Cu(phen)2]2+ cations and four lattice water molecules. They are further linked to form three-dimensional supramolecular networks through extensive hydrogen bonding and π–π stacking interactions. Interestingly, the water dimer and terminal oxygen of the cluster polyanion constitute a beautiful supramolecular helix chain. The heteropolyanion is the first example of tri-capped and mono-supported pseudo-Keggin-type tungstovanadophosphate and the pH value is crucial for obtaining compound 1 in synthetic procedure. 相似文献
5.
Bahri Ülküseven Tülay Bal-Demirci Mehmet Akkurt erife Pnar Yaln Orhan Büyükgüngr 《Polyhedron》2008,27(18):3646-3652
The reactions of 5-R-2-hydroxybenzaldehyde-4-allyl-thiosemicarbazone {R: H (L1); Br (L2)} with [MII(PPh3)nCl2] (M = Ni, n = 2 and M = Ru, n = 3) in a 1:1 molar ratio have given stable solid complexes corresponding to the general formula [Ni(L)(PPh3)] and [Ru(HL)2(PPh3)2]. While the 1:1 nickel complexes are formed from an ONS donor set of the thiosemicarbazone and the P atom of triphenylphosphine in a square planar structure, the 1:2 ruthenium complexes consist of a couple from each of N, S and P donor atoms in a distorted octahedral geometry. These mixed-ligand complexes have been characterized by elemental analysis, IR, UV–Vis, APCI-MS, 1H and 31P NMR spectroscopies. The structures of [Ni(L2)(PPh3)] (II) and [Ru(L1H)2(PPh3)2] (III) were determined by single crystal X-ray diffraction. 相似文献
6.
M. Padmanabhan James C. Joseph Xiaoying Huang Jing Li 《Journal of Molecular Structure》2008,885(1-3):36-44
Lewis-base mediated fragmentation of polymeric nickel(II) fumarate and oxalate are attempted using chelating σ-donor diamines like ethylenediamine (en) and 1,3-diaminopropane (dap) in various conditions which yielded [Ni(en)3](fum)·3H2O (1), [Ni(en)3](ox) (2), [Ni(dap)2(fum)] (3) and [Ni(dap)(ox)]·2H2O (4). While 1 and 2 are molecular products each containing octahedral [Ni(en)3]2+ moieties and the anionic dicarboxylate species, 3 and 4 are dap-incorporated polymeric products. The fumarate derivative 1 containing [Ni(en)3]2+ moieties crystallizes in the monoclinic space group C2/c with a = 17.899(4) Å, b = 11.747(2) Å, c = 10.748(2) Å, β = 125.59(3)°, V = 1837.7(6) Å3, Z = 4, while the oxalate analogue 2 is seen to be in the trigonal space group P−31c with a = 8.8770(13) Å, b = 8.8770(13) Å, c = 10.482(2) Å, γ = 120°, V = 715.3(2) Å3, Z = 2. The octahedral [Ni(en)3] units in both 1 and 2 are seen to be strongly H-bonded to the dicarboxylate moieties through the coordinated en units leading to a three-dimensional network. However, in 1 the water molecules also take part in the H-bonding and contribute to the overall 3D structure. In both 1 and 2 the crystal packing is done with the [Ni(en)3]2+ units with absolute configuration Λ(δδδ) and its mirror conformer with Δ configuration in exactly equal numbers. Spectral (IR and UV–Visible) and magnetic measurements were carried out and some of the ligand-field parameters like Dq, B and β were evaluated for all the four compounds. These values suggest the presence of octahedrally coordinated nickel(II) in all the four complexes. Spectral data suggest that 3 has the two chelating dap moieties and the fumarate coordinated in η1 form through both its carboxylate moieties while 4 has one chelating dap and the oxalate moiety coordinated in η4-bis-chelating form. Though both 1 and 2 are made of the same type of [Ni(en)3]2+ units their thermograms give entirely different thermal features; 1 showing three clearly successive and step-wise dissociation of each en unit while 2 having a combined loss of two en units in the first thermal step. The relevant thermodynamic and kinetic parameters like Ea and ΔS also could be evaluated for various thermal steps for the compounds 1–4 using Coats–Redfern equation. 相似文献
7.
Franco Cecconi Carlo A. Ghilardi Stefano Midollini Annabella Orlandini Piero Zanello 《Polyhedron》1986,5(12):2021-2031
The reaction of hydrogen sulphide with [Co(H2O)6](BF4)2 and triethylphosphine in the presence of sodium tetraphenylborate or tetrabutylammonium hexafluorophosphate gave the paramagnetic clusters [Co6(μ3-S)8(PEt3)6](Y) (Y = BPh4, (1), PF6, (2)). These compounds can be easily reduced by sodium napthalenide to the diamagnetic species [Co6(μ3-S)8(PEt3)6] · 2C4H8O (3). The molecular structures of 1 and 3 have been established by single-crystal X-ray diffraction methods. Crystal data: (1) space group P
, a = 19.481(9), b = 15.562(7), c = 12.390(b) Å, α = 92.70(8), β = 94.50(7), γ = 94.10(9)°, Z = 2, (3) space group R
, a = 11.780(6) Å, α = 92.50(7)°, Z = 1. Both structures were solved by the heavy atom method and refined by full-matrix least-squares techniques to the conventional R factors values of 0.050 for 1 and 0.044 for 3 on the basis of 4251 and 1918 observed reflections, respectively. The two clusters [Co6(μ3-S)8)(PEt3)6]1+,0 are isostructural, the inner core consisting of an octahedron of cobalt atoms with all the faces symmetrically capped by triply bridging sulphur atoms. Each metal centre is additionally linked to a triethylphosphine group so that each cobalt atom is co-ordinated by four sulphur atoms and one phosphorus in a distorted square pyramidal environment. The addition of one electron whilst leaving unchanged the geometry of the inner framework, induces small changes in the structural parameters, the average Co---Co and Co---P distances being 2.794 (3) and 2.162 (2) Å for 1 and 2.817 (3) and 2.138 (2) Å for 3 respectively. Electrochemistry in non-aqueous solvents shows the electron-transfer sequence
The tricationic species is stable only in the short time of cyclic voltammetric tests. 相似文献
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8.
Investigation into the synthesis of reduced vanadium phosphate has led to the formation of a new form of the barium vanadium (III) pyrophosphate compound β-BaV2(P2O7)2. It is a polymorph of the previously known BaV2(P2O7)2, which is now labeled as the α-phase. The title compound crystallizes in the P-1 (No. 2) space group with a = 6.269(1) Å, b = 7.864(3) Å, c = 6.1592(9) Å, α = 101.34(2)°, β = 105.84(1)°, and γ = 96.51(2)°. The structure consists of corner-shared VO6 octahedra and PO4 tetrahedra that are connected in V-O-P-O-V and V-O-P-O-P-O-V bonding arrangements. This interesting three-dimensional framework is characterized by seven types of intersecting tunnels, three of which are occupied by the barium cation, while the others are empty. It is important to know that one of the empty tunnels has a relatively large window with a minimum diagonal distance of 4.41 Å, which facilitates a possible framework for a lithium ion insertion reaction. The barium atom has a 10-coordination sphere, BaO10, in which the oxygen atoms can be viewed as forming two intersecting pseudohexagonal planes. β-BaV2(P2O7)2 appears to form at a relatively higher temperature than its polymorph, α-BaV2(P2O7)2. A detailed structural analysis and structural comparison with the α-phase, as well as a brief comparison with SrV2(P2O7)2, are presented. 相似文献
9.
Lifeng Tan Yue Xiao Xiaohua Liu Sheng Zhang 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,73(5):858-864
Based on the ligand dppz (dppz = dipyrido-[3,2-a:2′,3′-c]phenazine), a new ligand pbtp (pbtp = 4,5,9,11,14-pentaaza-benzo[b]triphenylene) and its polypyridyl ruthenium(II) complexes [Ru(phen)2(pbtp)]2+ (1) (phen = 1,10-phenanthroline and [Ru(bpy)2(pbtp)]2+ (2) (bpy = 2,2′-bipyridine) have been synthesized and characterized by elemental analysis, ES-MS and 1H NMR spectroscopy. The DNA-binding of these complexes were investigated by spectroscopic methods and viscosity measurements. The experimental results indicate that both complexes 1 and 2 bind to CT-DNA in classical intercalation mode, and can enantioselectively interact with CT-DNA. It is interesting to note that the pbtp ruthenium(II) complexes, in contrast to the analogous dppz complexes, do not show fluorescent behavior when intercalated into DNA. When irradiated at 365 nm, both complexes promote the photocleavage of pBR 322 DNA. 相似文献
10.
Roy L. Beddoes Jonathan R. Hinchliffe David Moorcroft Mark W. Whiteley 《Journal of organometallic chemistry》1998,560(1-2)
Reaction of [MX(CO)2(η7-C7H7)] (M=Mo, X=Br; M=W, X=I) with two equivalents of CNBut in toluene affords the trihapto-bonded cycloheptatrienyl complexes [MX(CO)2(CNBut)2(η3-C7H7)] (1, M=Mo, X=Br; 2, M=W, X=I). The X-ray crystal structure of 2 reveals a pseudo-octahedral molecular geometry with an asymmetric ligand arrangement at tungsten in which one CNBut is located trans to the η3-C7H7 ring. Treatment of 2 with tetracyanoethene results in 1,4-cycloaddition at the η3-C7H7 ring to give [WI(CO)2(CNBut)2{η3-C9H7(CN)4}], 3. The principal reaction type of the molybdenum complex 1 is loss of carbonyl and bromide ligands to afford substituted products [MoBr(CNBut)2(η7-C7H7)] 4 or [Mo(CO)(CNBut)2(η7-C7H7)]Br. Reaction of [MoBr(CO)2(η7-C7H7)] with one equivalent of CNBut in toluene at 60°C affords [MoBr(CO)(CNBut)(η7-C7H7)], 5, which is a precursor to [Mo(CO)(CNBut)(NCMe)(η7-C7H7)][BF4], 6, by reaction with Ag[BF4] in acetonitrile. In contrast with the parent dicarbonyl systems [MoX(CO)2(η7-C7H7)], complexes of the Mo(CO)(CNBut)(η7-C7H7) auxiliary, 5 and 6, do not afford observable η3-C7H7 products by ligand addition at the molybdenum centre. 相似文献
11.
Three rare earth compounds, KEu[AsS4] (1), K3Dy[AsS4]2 (2), and Rb4Nd0.67[AsS4]2 (3) have been synthesized employing the molten flux method. The reactions of A2S3 (A = K, Rb), Ln (Ln = Eu, Dy, Nd), As2S3, S were accomplished at 600 °C for 96 h in evacuated fused silica ampoules. Crystal data for these compounds are: 1, monoclinic, space group P21/m (no. 11), a = 6.7276(7) Å, b = 6.7190(5) Å, c = 8.6947(9) Å, β = 107.287(12)°, Z = 2; 2, monoclinic, space group C2/c (no. 15), a = 10.3381(7) Å, b = 18.7439(12) Å, c = 8.8185(6) Å, β = 117.060(7)°, Z = 4; 3, orthorhombic, space group Ibam (no. 72), a = 18.7333(15) Å, b = 9.1461(5) Å, c = 10.2060(6) Å, Z = 4. 1 is a two-dimensional structure with 2∞[Eu(AsS4)]− layers separated by potassium cations. Within each layer, distorted bicapped trigonal [EuS8] prisms are linked through distorted [AsS4]3− tetrahedra. Each Eu2+ cation is coordinated by two [AsS4]3− units by edge-sharing and bonded to further two [AsS4]3− units by corner-sharing. Compound 2 contains a one-dimensional structure with 1∞[Dy(AsS4)2]3− chains separated by potassium cations. Within each chain, distorted bicapped trigonal prisms of [DyS8] are linked by slightly distorted [AsS4]3− tetrahedra. Each Dy3+ ion is surrounded by four [AsS4]3− moieties in an edge-sharing fashion. For compound 3 also a one-dimensional structure with 1∞[Nd0.67(AsS4)2]4− chains is observed. But the Nd position is only partially occupied and overall every third Nd atom is missing along the chain. This cuts the infinite chains into short dimers containing two bridging [As4]3− units and four terminal [AsS4]3− groups. 1 is characterized with UV/vis diffuse reflectance spectroscopy, IR, and Raman spectra. 相似文献
12.
Zhi-Hui Yi Xiao-Bing Cui Xiao Zhang Ji-Qing Xu Guang-Di Yang Yan Chen Tie-Gang Wang Xiao-Yang Yu 《Journal of Molecular Structure》2008,885(1-3):149-153
A novel polyoxometalate {[Ni(enMe)2]2[Ni(enMe)2(H2O)]2[As2W18Ni4(enMe)2O68]}·2H3O·2H2O (1) (enMe = 1,2-propylenediamine) has been synthesized and characterized, which is the first high-dimensional structure constructed from sandwich-type transition metal substituted tungstates and transition metal coordination groups. 相似文献
13.
Chelladurai Ganesamoorthy Maravanji S. Balakrishna Joel T. Mague 《Journal of organometallic chemistry》2009,694(21):3390-3394
The stoichiometric reaction of phenylene-1,4-diaminotetra(phosphonite), p-C6H4[N{P(OC6H4OMe-o)2}2]2 (P2NФNP2) (1) with [RuCl2(p-cymene)]2 in acetonitrile produces cis,cis-[{RuCl2(CH3CN)2}2(P2NФNP2)] (2), whereas the similar reaction of 1 with [RuCl2(p-cymene)]2 in THF medium affords a tri-chloro-bridged tetrametallic complex, [{(η6-p-cymene)Ru2(μ2-Cl)3Cl}2(P2NФNP2)] (3) irrespective of the stoichiometry and reaction conditions. The formation and structure of complexes 2 and 3 are assigned through various spectroscopic and micro analysis data. The molecular structure of 2 is confirmed by single crystal X-ray diffraction study. The catalytic activities of complexes 2 and 3 have been investigated in transfer hydrogenation reactions. 相似文献
14.
A.A. Pasynskii I.V. Skabitsky Yu.V. Torubaev S.G. Sakharov S.S. Shapovalov 《Journal of organometallic chemistry》2009,694(21):3997
The reaction of [Cp′Cr(CO)2(μ-SBu)]2 (1) (Cp′ = MeC5H4) with (PPh3)2Pt(PhCCPh) gives Cp′Cr(CO)2(μ-SBu)Pt(PPh3)2 (2) which could be regarded as a product of the substitution of acetylene ligand at platinum by a monomeric chromium–thiolate fragment. According to the X-ray diffraction analysis 2 contains single Cr–Pt (2.7538(15)) and Pt–S (2.294(2) Å) bonds while Cr–S bond (2.274(3) Å) is shortened in comparison with ordinary Cr–S bonds (2.4107(4)–2.4311(4) Å) in 1. The bonding between Cr–S fragment and platinum atom is similar to the olefine coordination in their platinum complexes. 相似文献
15.
The compound [(μ-H)3Re3(CO)8{(EtO)2POP(OEt)2}2] crystallises in the monoclinic space group P21/c with a 18.053(6), b 16.211(5), c 14.800(3) Å, β = 102.41(2)°, and Z = 4. Simultaneous refinement of a single parameter set to fit 3212 X-Ray (sin θ/λ) > 0.352 Å−1 and 1480 neutron data has led to final weighted residuals Rw(F) of 0.096 (X-Ray) and 0.095 (neutron). The molecule exhibits noncrystallographic C2 symmetry, with two edges of the Re3 triangle bridged by (OEt)2POP(OEt)2 ligands. The hydride ligands lie close to the trimetal plane with each hydride bridging an Re---Re vector. Average molecular parameters involving the hydride ligands are Re---H 1.812(17), Re---Re 3.282(17) Å, Re---H---Re 130(3) and H---Re---H 107.6(27)/dg. All eight carbonyl ligands are terminal, the ligand polyhedron being derived from that in H3Re3(CO)12 by substitution of four axial carbonyls by two bidentate phosphite ligands. 相似文献
16.
Two novel heterometallic trinuclear incomplete cubane-like clusters [(CH3CH2)4N][{M2CuS4}(edt)2(PPh3)] (M = Mo, W) have been synthesized by reaction of [(CH3CH2)4N]2[M2S4(edt)2] (M = Mo, W) with Cu(PPh3)2(dtp) [where edt is 1,2-ethane-dithiolato ligand, dtp is S2P(OCH2CH3)2−]. The two crystals are isomorphous in space group P1 (No. 1). The unit cell contains two independent molecules, but the two discrete anions have the same orientation for the PPh3 ligands along one axis so the space group is undoubtedly non-centrosymmetric. The discrete anion contains two edt ligands and one PPh3 ligand attached to one incomplete cubane-like cluster core {M2CuS4}3+ (M = Mo, W). The bond lengths of Mo---Mo[W---W] and the two Mo---Cu[W-Cu] are 2.852(2)[2.844(1)], 2.802(2)[2.765(3)], 2.760(2)[2.762(3)] Å, respectively. The M 2S4(edt)2 (M = Mo, W) moiety remains almost unchanged, except that for the compound 1 the Mo=S double bond length elongates from av. 2.10 to av. 2.165 Å. The title clusters provide a new type of unsymmetric μ2-bridging sulphido ligand. The incomplete cubane-like cluster core {Mo2CuS4}3+ of compound 1 is distorted because the two Cu---μ2---S bond lengths are significantly different (2.313 Å and 2.409 Å), but the core {W2CuS4}3+ of compound 2 has approximately Cs symmetry. The IR spectra of the two title clusters and two starting materials are assigned. 相似文献
17.
The nature of the protonation reaction of (
o(CO)3 (M = Mo, W; R = Me, Ph, p-MeC6H4) (2) (obtained from (CO)3CpMCH2CCR (1) and Co2(CO)8) to give (CO)3
Cp(CO)2 (3) was further investigated by a crossover experiment. Thus, reaction of an equimolar mixture of 2b (M = W, Cp = η5-C5H5, R = Ph) and 2e (M = W, Cp = η5-C5H4Me; R = p-MeC6H4) with CF3COOH affords only 3b (same M, Cp, and R as 2b) and 3e (same M, Cp, and R as 2e) to show an intramolecular nature of this transformation. Reaction of (CO)3CpWCH2CCPh (1b) with Co4(CO)12 was also examined and found to yield 2b exclusively. Treatment of 1 with Cp2Mo2(CO)4 at 0–5°C provides thermally sensitive compounds, possibly (CO)2Cp
oCp(CO)2 (5), which decompose at room temperature to give Cp2Mo2(CO)6 as the only isolated product. 相似文献
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18.
Nabila El-Azzouzi Francisco Hueso-UreñaNuria A. Illán-Cabeza Miguel N. Moreno-Carretero 《Polyhedron》2010
The XRD structure of two seven-coordinated Mn(II) complexes with the formula [Mn(phen)(nicot)(NO3)(H2O)]·EtOH·H2O (1) and [Mn(phen)(NO3)2(H2O)] (2) are reported. The 2,9-dimethyl-1,10-phenanthroline, nitrato and nicotinato anions act as bidentate ligands, with Mn–N distances of 2.21–2.29 Å and Mn–O distances of 2.17–2.40 Å. In both compounds, the water molecule seems to be the strongest coordinated ligand, with bond distances of 2.139(2) Å in 1 and 2.195(2) Å in 2. The average ratio between coordinated unidentate and bidentate bond lengths less than the unity justifies, from an energetical point of view, the shape of the coordination polyhedra. In the structure of 1, the coordination polyhedron may be best-described as a distorted pentagonal bipyramid with a nitrogen from phenanthroline and the water molecule occupying the apical sites. The polyhedron shape for 2 is close to a square-capped trigonal prism, the capping site being occupied by the water molecule. The crystal structures are built by H-bonded bidimensional sheets piled up by π–π stacking of the partially interpenetrated aromatic moieties of adjacent layers. 相似文献
19.
Herbert Schumann Juliane A. Meese-Marktscheffel Andreas Dietrich Frank H. Grlitz 《Journal of organometallic chemistry》1992,430(3)
Metathesis of LuCl3, NaCp and Li(CH2)3NMe2 in the molar ratio 1:2:1 affords the lutetium alkyl species Cp2
Me2 (1); analogous reaction of LuCl3, NaMeC5H4 and LiCH2CH(Me)-CH2NMe2 generates the corresponding complex (MeC5H4)2
Me2] (2). Treatment of YCl3 with two equivalents of NaCp and one equivalent of Li(CH)3NMe2 yields, in the presence of CO2, the yttrium carboxylate Cp2Y[η2-O2C(CH2)3NMe2 (3). Mass spectrometrical studies of the solvent-free rare earth triflates [Cp2Ln(OSO2CF3)]2 (Ln = Sc (4), Lu (5)) have shown them to be dimeric. The crystal structures of 1 and 3 were determined by X-ray diffraction methods. 1 crystallizes in the monoclinic space group P21 (No. 4) with the unit-cell parameters a 657.0(4), b 1386.7(8), c 803.5(3) pm, β 106.64(5)°, V 704(1) × 10−30 m3 and Z = 2. The structure was solved on the basis of 1094 observed reflections with F0 ≥ 3σ(F0) and refined to a final R value of 0.0483. With the short Lu---N bond length of 237(1) pm the molecular structure of 1 exhibits an intramolecular N → Lu coordination. The crystals of 3 are triclinic, space group P
(No. 2), with a 1078.2(6), b 1533.0(9), c 1020.3(8) pm, α 109.47(6), β 82.75(6), γ 88.99(5)°, V 1574(2)×10−30 m3 and Z = 4. Least-squares refinement of the model based on 1659 observed reflections converged to R = 0.093 (F0 ≥ 5σ(F0)). The structural data of 3 feature a monomer with a chelating carboxylate group. The long Y---N distance (499 pm) excludes any intramolecular N---Y interactions. 相似文献
20.
Junes Ipaktschi Katja Reimann Michael Serafin Ansgar Dülmer 《Journal of organometallic chemistry》2003,670(1-2):66
Treatment of the η1-acetylide complex [(η5-C5H5)(CO)(NO)W---CC---C(CH3)3]Li (4) with 1,2-diiodoethane in THF at −78 °C, followed by the addition of Li---CC---R [R=C(CH3)3, C6H5, Si(CH3)3, 6a–6c] or n-C4H9Li and protonation with H2O, afforded the corresponding oxametallacyclopentadienyl complexes (η5-C5H5)W(I)(NO)[η2-O=C(CC---R)CH=CC(CH3)3] (7a–7c), 8c and (η5-C5H5)W(I)(NO)[η2-O=C(n-C4H9)CH=CC(CH3)3] (9). The formation of these metallafuran derivatives is rationalized by the electrophilic attack of 1,2-diiodoethane onto the metal center of 4 to form first the neutral complex [(η5-C5H5)(I)(CO)(NO)W---CC---C(CH3)3] (5). Subsequent nucleophilic addition of Li---CC---R 6a–6c or n-C4H9Li and a reductive elimination step followed by protonation leads to the products 7a–7c and 9. One reaction intermediate could be trapped with CF3SO3CH3 and characterized by a crystal structure analysis. The identity of another intermediate was established by infrared spectroscopic data. The oxametallacyclopentadienyl complex 10 forms in the presence of excess 1,2-diiodoethane through an alternative pathway and crystallizes as a clathrate containing iodine. 相似文献