共查询到20条相似文献,搜索用时 15 毫秒
1.
Valerie F. Allen Ronald Mason Peter B. Hitchcock 《Journal of organometallic chemistry》1977,140(3):297-307
X-ray crystallographic analyses of H2Os3(CO)10, H(SC2H5)Os3(CO)10 and (OCH3)2Os3(CO)10 are reported. Although hydrogen atom positions have not been located, the essential isostructural nature of the three commplexes establishes the hydride ligands as bridging two metal atoms, separated by 2.670 Å, with a formal bond order of two; the bridging hydrido- and thiolato-ligands span an osmium---osmium bond of length 2.863 Å and formal bond order one; the two μ-methoxy ligands bridge two metal atoms separated by 3.078 Å which, by simple 18 electron rule counting, has a metal---metal bond order of zero. Some general comments are made on the structures of polynuclear transition metal carbonyls. 相似文献
2.
Fujico Iwasaki Martin J. Mays Paul R. Raithby Philip L. Taylor Peter J. Wheatley 《Journal of organometallic chemistry》1981,213(1):185-206
Twelve new trinuclear complexes containing terminal PH2Ph, edge-bridging PHPh and/or capping PPh ligands have been isolated from the reaction of M3(CO)12 (M = Ru or Os) with PH2Ph in refluxing solvents. HRu3(CO)10(PHPh) (IIIa) crystallises in the monoclinic space group P21/c with a = 8.761(3), b = 11.402(4), c = 22.041(7) Å,β = 98.89(2)°, and Z = 4. The structure was solved by a combination of direct methods and Fourier difference techniques, and refined by blocked-cascade least squares to R = 0.027 for 3676 unique observed intensities. The X-ray analysis shows that one edge of the Ru3 triangle is bridged by a hydride and the PHPh ligand, and that the phosphorus-bound hydrogen atom lies over the metal triangle and the phenyl group away from it. This provides an explanation for the ready formation of the capped species H2Ru3(CO)9(PPh) (Va) on pyrolysis of the edge-bridged complex as opposed to the previously reported conversion of HOs3(CO)10(NHPh) to an orthometallated derivative under similar conditions. An X-ray analysis of H2Ru3(CO)9-(PPh) (Va) confirms the capped geometry. the complex crystallises in the monoclinic space group P21/n with a = 9.323(4), b = 15.110(6), c = 45.267(15) Å,β = 91.84(3)°, and Z = 12. the structure was solved and refined using the same techniques as described previously. The final residual R is 0.061 for 4839 reflections. Some reactions of Va show that the phosphorous cap is difficult to displace and stabilises the molecule with respect to decomposition to non-cluster species. 相似文献
3.
Jouni Pursiainen Tapani A. Pakkanen Juhani Jääskeläinen 《Journal of organometallic chemistry》1985,290(1):85-98
A new ruthenium-rhodium mixed-metal cluster HRuRh3(CO)12 and its derivatives HRuRh3(CO)10(PPh3)2 and HRuCo3(CO)10(PPh3)2 have been synthesized and characterized. The following crystal and molecular structures are reported: HRuRh3(CO)12: monoclinic, space group P21/c, a 9.230(4), b 11.790(5), c 17.124(9) Å, β 91.29(4)°, Z = 4; HRuRh3(CO)10(PPh3)2·C6H14: triclinic, space group P, a 11.777(2), b 14.079(2), c 17.010(2) Å, α 86.99(1), β 76.91(1), γ 72.49(1)°, Z = 2; HRuCo3(CO)10(PPh3)2·CH2Cl2: triclinic, space group P, a 11.577(7), b 13.729(7), c 16.777(10) Å, α 81.39(4), β 77.84(5), γ 65.56°, Z = 2. The reaction between Rh(CO)4? and (Ru(CO)3Cl2)2 tetrahydrofuran followed by acid treatment yields HRuRh3(CO)12 in high yield. Its structural analysis was complicated by a 80–20% packing disorder. More detailed structural data were obtained from the fully ordered structure of HRuRh3(CO)10(PPh3)2, which is closely related to HRuCo3(CO)10(PPh3)2 and HFeCo3(CO)10(PPh3)2. The phosphines are axially coordinated. 相似文献
4.
R. Psaro R. Ugo G.M. Zanderighi B. Besson A.K. Smith J.M. Basset 《Journal of organometallic chemistry》1981,213(1):215-247
5.
采用密度泛函理论(DFT)中的广义梯度近似(GGA)方法对C56X10(X=F, Cl, Br, I)的结构稳定性和电子性质进行了计算研究. 结构稳定性计算表明: 对于C56X10(X=F, Cl, Br, I), 能隙、反应热、最大振动频率和最小振动频率都随着X原子序数的增加而减小, 表明C56X10(X=F, Cl, Br, I)的稳定性随着X原子序数的增加而逐渐降低, 其中C56F10最为稳定. 前人在实验上已成功合成出C56Cl10, 因此, 我们推测C56F10有望在实验上成功合成. 前线轨道计算发现, C56相邻的五边形公共顶点以及两个六边形-五边形-六边形公共顶点是笼子中化学活性最强的部位, 有利于卤族元素的外部吸附. 此外, 计算结果还显示, C56X10(X=F, Cl, Br, I)的电负性随着X原子序数的增大而逐渐减弱, C—X基团的电负性因位置的不同而不同. 相似文献
6.
B. Slootmaekers A.C. Fabretti H.O. Desseyn R. Vochten S.P. Perlepes 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》1996,52(14):1883-1896
In this article, the preparation, X-ray powder results and vibrational properties of a new type of complex with planar dithiooxamides are discussed. In acetonitrile, Cu(I) can form complexes with the formula Cu(LH2)2X1 (X = Cl, Br) where LH2 is an N,N'-disubstituted dithiooxamide. Complexes with N,N'-dimethyldithiooxamide and N,N'-diethyldithiooxamide have been prepared. A thorough vibrational analysis with infrared and Raman techniques was performed, assisted by H/D and 63Cu/65Cu isotope substitution. The vibrational study indicates the presence of an inversion centre in the structure. This leads to the proposal of a very unusual six-coordinate structure for these compounds, with the two dithiooxamide ligands, having S-cis conformation, coordinated to the same copper and with the halogens bridged between two different copper atoms. Confirmation of this result was attempted by X-ray analysis, but although several methods were tried to obtain crystals, only powder X-ray data could be obtained, which could not give a definitive answer. Since such six-coordinate Cu(I) has never been described before, a less rigourous interpretation of the vibrational data was followed, leading to a square-pyramidal five-coordinate structure, with a rather weak bond between Cu(I) and a terminal halogen. The latter structure, with the data available up to now, seems a bit more likely, since five-coordination for Cu(I) has already been described. 相似文献
7.
Polarized single-crystal absorption spectra of CsVCl3, CsVBr3 and CsVI3 have been measured between 5000 and 30000 cm?1 at temperatures ranging from 6 to 273 K. Spin-allowed transitions arise through a vibronic single-ion mechanism. Spin-forbidden transitions are strongly enhanced through an exchange intensity mechanism. 相似文献
8.
The IR spectra of cis- and trans-[Pt(pyridine)2X2] (X = Cl, Br, I, SCN) are discussed. Distinction between the vPt—N and vPt—X bands is based on their relative sensitivities to 15N-labelling and deuteration of the pyridine ring, to halogen substitution and to 15NCS-labelling. Two vPt—N and two vPt—X bands are observed in the cis-complexes as required for C2v symmetry. The D2h symmetry of the trans-complexes requires one vPt-N and one vPt—X band but additional bands are observed and are ascribed to coupling between vPt—N and vPt—X. 相似文献
9.
Alireza Ariafard 《Journal of organometallic chemistry》2004,689(14):2275-2283
A set of phosphine complexes of the type W(CO)3(PX3)2(CH2CH2) (X=H, CH3, F, Cl, Br, and I) were investigated by density functional theory method (BP86) to examine the effect of the substituent X on the orientation of C-C vector of the ethylene ligand with respect to one of the metal-ligand bonds as well as the donation and the backdonation in the bonding ligands of phosphine and ethylene. When X=CH3, H, F, and Cl, the ethylene C-C vector prefers to be coplanar with metal-phosphine bonds, while for the ethylene complexes containing PBr3 and PI3 ligands, the structural preference is coplanarity of the ethylene and the metal-carbonyl bonds. The molecular orbital calculations and natural bond orbital analysis were used to examine the structural consequences derived from these complexes. It can be concluded that the structural preferences in the complexes have a clear relation to electronic effects of phosphine ligands. Our calculations for halide phosphine complexes, particularly for PBr3 and PI3, allow us to conclude that in addition to electronic effects, steric factors can also affect the orientation of the ethylene ligand in complexes. 相似文献
10.
The reactions of FeX2 (X = Cl, Br or I) with pyrazine (pyz) yield the Fe(pyz)2X2 compounds. Examination of IR and Raman spectra in the medium- and far-IR region as well as studies of electronic and Mössbauer spectra suggests that the complexes contain six-coordinate high-spin Fe(II) in the FeN4X2 chromophore. The complexes have a polymeric pseudo-octahedral pyz-bridged structure. The magnetic moments are independent of temperature and low-temperature magnetic measurements do not indicate any magnetic ordering above 4.2 K in these compounds. The π-acceptor properties of pyz are reflected both in the electronic spectra evaluated in terms of the angular overlap model and the Mössbauer parameters. 相似文献
11.
After exposure to γ rays at 77 K. (CH3)2AlX (X = Cl, Br,or I) in solid solutions of tetramethylsilane gave six-line ESR spectra with a large hyperfine coupling characteristic of 27Al and an additional halogen splitting. The results indicate the formation of (CH3)2A1X? with pyramidal structure. The unpaired electron occupies a π* orbital composed largely of 3s and 3p Al orbiials and slightly of halogen orbitals. 相似文献
12.
Richard D. Adams Burjor Captain Wei Fu Mark D. Smith Lei Zhu 《Journal of Cluster Science》2006,17(1):87-95
Two new compounds Pd2Os3(CO)12
, 13 and Pd3Os3(CO)12
, 14 have been obtained from the reaction of
with Os3(CO)12 at room temperature. The products were formed by the addition of two and three
groups to the Os–Os bonds of Os3(CO)12. Compounds 13 and 14 interconvert between themselves by intermolecular exchange of the
groups in solution. Compounds 13 and 14 have been characterized by single crystal X-ray diffraction analyses.Dedicated to Professor Brian F. G. Johnson on the occasion of his retirement – 2005. 相似文献
13.
The reactions of the substituted Group VI metal carbonyls of the type M(CO)4(2-Mepy)2 (M = Mo, w) and M(CO)3(L)3 (L = py, M = Mo, W; L = NH3, M = Mo) with mercuric derivatives HgX2 (X = Cl, CN, SCN) have given rise to three series of tricarbonyl complexes: M(CO)3(py)HgCl2 · 1/2HgCl2 (M = Mo, W); 2[M(CO)3(L)]Hg(CN)·nHg(CN)x (L = py, M = Mo, W, n = , × = 2; L = 2- Mepy, × = 1; M = Mo, n = 3; M = W, n = 1); and [M(CO)3(L)Hg(SCN)2 · nHg(SCN)2] (L = py, M = Mo,W, n = 0; L = 2-Mepy, M = Mo, W, n = ; L = NH3, M = Mo, n = 0) depending on which mercuric compound is employed. All the reactions with Hg(SCN)2 give isolable products whereas those with Hg(CN)2 and HgCl2 did so far only the reactions with [M(CO)4(2-Mepy)2] and M(CO)3(py)3. The greater reactivity of Hg(SCN)2 than of Hg(CN)2 and HgCl2 is consistent with the various acceptor capacities of the groups bonded to the mercury atom.The reactions studied always involve displacement of the N-donor ligand of the original complex and partial or total displacement of the halide or pseudohalide groups of the mercury compound to give in all cases compounds containing MHg bonds. In addition, elimination of a CO group in the tetracarbonyl complexes M(CO)4(2-Mepy)2occurs. 相似文献
14.
Taku Katayama Kiyotaka Onitsuka Shigetoshi Takahashi 《Journal of organometallic chemistry》2000,610(1-2):31-37
Treatment of ruthenium complexes [CpRu(AN)3][PF6] (1a) (AN=acetonitrile) with iron complexes CpFe(CO)2X (2a–2c) (X=Cl, Br, I) and CpFe(CO)L′X (6a–6g) (L′=PMe3, PMe2Ph, PMePh2, PPh3, P(OPh)3; X=Cl, Br, I) in refluxing CH2Cl2 for 3 h results in a triple ligand transfer reaction from iron to ruthenium to give stable ruthenium complexes CpRu(CO)2X (3a–3c) (X=Cl, Br, I) and CpRu(CO)L′X (7a–7g) (L′=PMe3, PMe2Ph, PMePh2, PPh3, P(OPh)3; X=Br, I), respectively. Similar reaction of [CpRu(L)(AN)2][PF6] (1b: L=CO, 1c: P(OMe)3) causes double ligand transfer to yield complexes 3a–3c and 7a–7h. Halide on iron, CO on iron or ruthenium, and two acetonitrile ligands on ruthenium are essential for the present ligand transfer reaction. The dinuclear ruthenium complex 11a [CpRu(CO)(μ-I)]2 was isolated from the reaction of 1a with 6a at 0°C. Complex 11a slowly decomposes in CH2Cl2 at room temperature to give 3a, and transforms into 7a by the reaction with PMe3. 相似文献
15.
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
16.
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
Full-size image (1K)
Full-size image (1K)
17.
Reaction of 1,3,5-trimethyl-1,3,5-triazacyclohexane [(MeNCH2)3] with Os3(CO)12 in refluxing toluene results in C-H and C-N bond activation of the (MeNCH2)3 ligand to afford three amidino cluster complexes (μ-H)Os3(CO)10[μ,η2-CH(NMe)2] (1), (μ-H)Os3(CO)9[μ3,η2-CH(NMe)2] (2), and Os2(CO)6[μ,η2-CH(NMe)2]2 (3). The controlled experiments show that thermolysis of 1 yields 2, and heating 2 in the presence of (MeNCH2)3 ligand produces 3. The molecular structures of 1 and 3 have been determined by an X-ray diffraction study. 相似文献
18.
M.K. Chaudhuri A. Haas M. Rosenberg M. Velicescu N. Welcman 《Journal of organometallic chemistry》1977,124(1):37-47
Mass spectra of Fe3(CO)9X2 (X S, Se, Te) and Fe2(CO)6X′2 (X′ S, Se) are recorded and their fragmentation pattern given. The thermal decarbonylation has been studied using DTA/TG methods in the temperature range 25–600°C. The results are compared with those obtained from mass-spectroscopic studies. X-ray and magnetic measurements have been carried out on the residues obtained in the decarbonylation process. 相似文献
19.
Tsutomu Okuda Haruhito Kando Hideta Ishihara Koji Yamada Hisao Negita 《Journal of Molecular Structure》1985,130(3-4):309-316
NQR spectra were observed for α-(CH3)2 TeX2 (X=Cl, Br, I) and (CH3)2 TeI4 at various temperatures. The two 81Br NQR lines were observed above 110 K in α-(CH3)2TeBr2. The characteristic temperature dependence of the 127I NQR line in α-(CH3)2 TeI. can be explained by the 3c—4e bond of the linear I---Te---I group. The positive temperatures dependence of the lowest 127I NQR line in (CH3)2TeI4 is discussed on the basis of the electron population calculated from Townes—Dailey treatment. 相似文献
20.
Taisuke Nakanaga Hidekazu Nagai Atsushi Suzuki Yukio Fujiwara Hidehiko Nonaka 《Journal of photochemistry and photobiology. A, Chemistry》2008,197(2-3):266-272
Multiphoton ionization and the subsequent dissociation process of metal cluster complexes Os3(CO)12 and Ir4(CO)12, prepared in a supersonic jet, were studied by means of multiphoton ionization with time-of-flight (TOF) mass detection. The ionization energies of Os3(CO)12 and Ir4(CO)12 were determined to be 7.95 and 8.3 eV, respectively, from the laser wavelength at the ionization threshold. The coordination energies of Os3(CO)12+ and Ir4(CO)12+ ions were also determined to be 1.6 and 1.2 eV, respectively, from the excitation energy needed to cause the appearance of fragment ions. The observed values agreed reasonably well with the ones calculated by using the density functional theory method. 相似文献