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1.
The compound [Pb3Zr7(4-O)4 (3-O)4(O2CCH3)8 (OPri)10] has been isolated from a reaction mixture containing known Pb-Zr and Pb-Ti complexes and characterised by 207Pb and 1 H NMR and IR spectroscopy. The compound crystallises in the space group P with a = 13.778(4) Å, b = 21.916(5) Å, c = 27.768(10) Å; = 86.52(3)°, = 87.68(3)°, = 72.72(2)° V 7989(4) Å3, Z = 4, R = 0.0973. A Pb-Zr alkoxide complex containing acetylacetone has also been synthesised using PbO as a reagent having the composition [Pb2Zr4(O)2 (OiPr)6(OnPr)8 (acac)2] allocated on the basis of MW, mass spectral and 1H NMR data.  相似文献   

2.
Two new oxo-centered trinuclear iron complexes [Fe3(μ3-O)(μ-O2CEt)6(H2O)3]Cl.3H2O 1 and [Fe3(μ3-O)(μ-O2CEt)6Py3]Cl 2 were prepared in non-aqueous solvent and their crystal structures have been determined. Crystal 1 is monoclinic, space group P21/n, a=9.909(3), b=24.467(8), c=14.542(7)(), β=107.85(4)° V=3356(4)()3, Z=4, Mr=765.52, Dc=1.52 g/cm3, μ=14.28 cm-1, F(000)=1588 and R=0.059, Rw=0.071 for 3745 unique reflections with I>3σ(I). Crystal 2 belongs to the monoclinic system with space group C2/c, a=13.750(3), b=18.439(4), c=16.696(3)(), β=93.42(3)°, V=4226(3)()3, Z=4, Mr=894.73, Dc=1.41 g/cm3, μ=11.4 cm-1, F(000)=2322 and R=0.058, Rw=0.062 for 2272 unique reflections with I>3σ(I). The two structures contain the same trimetal framework in which three iron(Ⅲ) atoms form a nearly equilateral triangle with a μ3-oxygen atom in the centre.  相似文献   

3.
<正> The title compound was obtained by the reaction of Mo3(μ3-O) (μ-S)3(dtp)4(H2O) with CH3COONa and pyridine. Mo3C19H38N1O9P3S9,Mr= 1093. 79, triclinic, space group P1, a = 12. 921(3) , b = 14. 260(3) , c= 12. 800(3)(?),α = 97. 54(2), β=116. 66(1), γ=100. 10(2) °, V = 2015, 2(8)(?)3, Z=2, Dc = 1. 80gcm-3, F(000) = 1092, final R = 0. 066 for 3444 observations, room temp. In the structure the three Mo atoms form an isosceles triangle capped by a μ3-O atom with three sides of 2. 589(2) , 2. 642(2), and 2. 627(2) (?) respectively, and the car-boxyl bridged Mo-Mo bond is the shortest one.  相似文献   

4.
标题簇合物系通过液相氧化低价钼(MoCl3)制得,晶体属正交晶系,空间群为D2h[16]-Pmnb,晶胞参数:α=11.403(1),b=12.345(2),c=14.292(2)A,V=2011.8(8)A[3].Z=4,Dc=2.396g.cm[-3].使用四圆衍射仪收集衍射数据,晶体结构用重原子法解出,经全矩阵最小二乘修正,R=0.050,Rw=0.056.簇阴离子结构属M1型三核钼簇构型,Mo-Mo键2.577A;Mo-O-μ3键1.982A.还讨论了桥原子、键级以及配体对Mo-Mo键的影响。  相似文献   

5.
Abstract

[Cu(O2CCH3)2]2, 1, reacts with pyridine to form violet-blue Cu(O2CCH3)2(pyridine)3, 2, in > 90% yield. 2 crystallizes from pyridine with a distorted square-pyramidal geometry around copper with the monodentate acetate ligands located diagonally in the basal positions. 1 reacts with Bi(OCMe3)3 in THF to form blue Cu6(μ-O2CCH3)44-O2CCH3)2(μ-OCMe3)6, 3. 3 crystallizes from THF/hexanes with a hexagon of copper atoms linked by six doubly-bridging tert-butoxide ligands, four doubly-bridging bidentate acetates, and two quadruply-bridging bidentate acetate ligands.  相似文献   

6.
<正> (Et4N)[Mo3(μ3-O)(μ-Cl)3(μ-OAc)3Cl3], C14H29Cl6Mo3NO7, Mr = 823.92, triclinic, P1, a = 17. 508(4), b = 19. 602(3), c=8. 091(2)A, α=91. 25(2)°, β= 96. 56(2)°,γ= 83. 61(2)°, V = 2741(1)A3, Z = 4, Dc = 2.00g/cm3, MoKa (λ=0. 71069A), μ= 19. 44cm-1, F(000) = 1616, T = 23℃, final R = 0. 055, Rw = 0. 068 for 5728 unique intensity data (I≥3σ(I)).The molecule consists of cluster aniorn [Mo3(μ3-O) (μ-Cl)3(μ-OAc)3Cl3]- and cation (Et4N) + . There are two independent molecules in an asymmetric unit whose cluster anions A and B have the same configuration except for some bonding parameters. The cluster core may be described as an equilateral {Mo3} triangle with a capping O atom and three bridging Cl atoms below and above it respectively. In addition, each pair of Mo atoms is bridged by an acetate group and each Mo atom is further coordinated to a terminal chlorine atom. The three Mo - Mo bonds are 2. 587 (2), 2.587(2), 2. 582(2) A for cluster anion A and 2. 587(2), 2.595(2), 2.577 (2) A for cluster a  相似文献   

7.
<正> Mr=963.9, monoclinic, P21/c, a=11.379(3), b=20.766(2), c=14.487(3) A,β=91.49(2)°, V=3518.9A3, Z=4, Dm=1.81, Dx=1.819 g·cm-3, MoKα radiation, λ=0.71073A, μ=18.167, F(000)=1916, T=293 K, R=0.040 for 3261 reflections. The structure consists of two sets of tetraethylammonium cations and trinuclear Mo cluster anions. The cluster skeleton is formed by three Mo atoms arranged in an isosceles triangle with a Cl and an O atoms as capping ligands.  相似文献   

8.
<正> The title complex C CrMo3 (μ3-O )3 (μ-O) (μ-O2CCH3 )5 (O2CCH3)3]2Na2 · H2O (Mr=1814. 32) crystallizes in monoclinic, space group P21/ n with a=11.209(5), b=18. 05(1), c=14. 44(1) A , β= 98. 30(5)°. V=2890 (3) A3, Z=2, A = 2. 08 g/cm3, F(000) -1780, Final R = 0. 049, Rw = 0. 058 for 2622 independent reflectons with I>3σ(I). The complex anion contains two Mo3O4 cores which connect two chromium atoms through four μ3-O atoms and eight bridging CH3COO- groups. Each of the Cr atoms and the Mo atoms is coordinated by six oxygen atoms. The anions are linked by Na cations to form one-dimensional infinite chain structure.  相似文献   

9.
A comparison of the electrochemical properties of a series of dinuclear complexes [M(2)(L)(RCO(2))(2)](+) with M = Mn or Co, L = 2,6-bis(N,N-bis-(2-pyridylmethyl)-sulfonamido)-4-methylphenolato (bpsmp(-)) or 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato (bpbp(-)) and R = H, CH(3), CF(3) or 3,4-dimethoxybenzoate demonstrates: (i) The electron-withdrawing sulfonyl groups in the backbone of bpsmp(-) stabilize the [M(2)(bpsmp)(RCO(2))(2)](+) complexes in their M(II)(2) oxidation state compared to their [M(2)(bpbp)(RCO(2))(2)](+) analogues. Manganese complexes are stabilised by approximately 550 mV and cobalt complexes by 650 mV. (ii) The auxiliary bridging carboxylato ligands further attenuate the metal-based redox chemistry. Substitution of two acetato for two trifluoroacetato ligands shifts redox couples by 300-400 mV. Within the working potential window, reversible or quasi-reversible M(II)M(III)? M(II)(2) processes range from 0.31 to 1.41 V for the [Co(2)(L)(RCO(2))(2)](+/2+) complexes and from 0.54 to 1.41 V for the [Mn(2)(L)(RCO(2))(2)](+/2+) complexes versus Ag/AgCl for E(M(II)M(III)/M(II)(2)). The extreme limits are defined by the complexes [M(2)(bpbp)(CH(3)CO(2))(2)](+) and [M(2)(bpsmp)(CF(3)CO(2))(2)](+) for both metal ions. Thus, tuning the ligand field in these dinuclear complexes makes possible a range of around 0.9 V and 1.49 V for the one-electron E(M(II)M(III)/M(II)(2)) couple of the Mn and Co complexes, respectively. The second one-electron process, M(II)M(III)? M(III)(2) was also observed in some cases. The lowest potential recorded for the E°(M(III)(2)/M(II)M(III)) couple was 0.63 V for [Co(2)(bpbp)(CH(3)CO(2))(2)](2+) and the highest measurable potential was 2.23 V versus Ag/AgCl for [Co(2)(bpsmp)(CF(3)CO(2))(2)](2+).  相似文献   

10.
The syntheses, single crystal X-ray structures, and magnetic properties of the homometallic μ?-oxo trinuclear clusters [Fe?(μ?-O)(μ-O?CCH?)?(4-Phpy)?](ClO?) (1) and [Fe?(μ?-O)(μ-O?CAd)?(4-Mepy)?](NO?) (2) are reported (Ad = adamantane). The persistence of the trinuclear structure within 1 and 2 in CD?Cl? and C?D?Cl? solutions in the temperature range 190-390 K is demonstrated by 1H NMR. An equilibrium between the mixed pyridine clusters [Fe?(μ?-O)(μ-O?CAd)?(4-Mepy)(3-x)(4-Phpy)(x)](NO?) (x = 0, 1, 2, 3) with a close to statistical distribution of these species is observed in CD?Cl? solutions. Variable-temperature NMR line-broadening made it possible to quantify the coordinated/free 4-Rpy exchanges at the iron centers of 1 and 2: k(ex)2?? = 6.5 ± 1.3 × 10?1 s?1, ΔH(?) = 89.47 ± 2 kJ mol?1, and ΔS(?) = +51.8 ± 6 J K?1 mol?1 for 1 and k(ex)2?? = 3.4 ± 0.5 × 10?1 s?1, ΔH(?) = 91.13 ± 2 kJ mol?1, and ΔS(?) = +51.9 ± 5 J K?1 mol?1 for 2. A limiting D mechanism is assigned for these ligand exchange reactions on the basis of first-order rate laws and positive and large entropies of activation. The exchange rates are 4 orders of magnitude slower than those observed for the ligand exchange on the reduced heterovalent cluster [Fe(III)?Fe(II)(μ?-O)(μ-O?CCH?)?(4-Phpy)?] (3). In 3, the intramolecular Fe(III)/Fe(II) electron exchange is too fast to be observed. At low temperatures, the 1/3 intermolecular second-order electron self-exchange reaction is faster than the 4-Phpy ligand exchange reactions on these two clusters, suggesting an outer-sphere mechanism: k?2?? = 72.4 ± 1.0 × 103 M?1 s?1, ΔH(?) = 18.18 ± 0.3 kJ mol?1, and ΔS(?) = -90.88 ± 1.0 J K?1 mol?1. The [Fe?(μ?-O)(μ-O?CCH?)?(4-Phpy)?](+/0) electron self-exchange reaction is compared with the more than 3 orders of magnitude faster [Ru?(μ?-O)(μ-O?CCH?)?(py)?](+/0) self-exchange reaction (ΔΔG(exptl)(?298) = 18.2 kJ mol?1). The theoretical estimated self-exchange rate constants for both processes compare reasonably well with the experimental values. The equilibrium constant for the formation of the precursor to the electron-transfer and the free energy of activation contribution for the solvent reorganization to reach the electron transfer step are taken to be the same for both redox couples. The larger ΔG(exptl)(?298) for the 1/3 iron self-exchange is attributed to the larger (11.1 kJ mol?1) inner-sphere reorganization energy of the 1 and 3 iron clusters in addition to a supplementary energy (6.1 kJ mol?1) which arises as a result of the fact that each encounter is not electron-transfer spin-allowed for the iron redox couple.  相似文献   

11.
<正> The title compound was prepared by reaction of Mo3(μ3-O) (μ-S)3-(dtp)4 (H2O) with C6H5COONa and pyridine. C27 H35 Mo3NO9P2S7, Mr = 1091.76, monoclinic, space group P21/c, a = 15. 057(5), b = 13. 052(5), c = 21. 662(6)(?), β=105.97(2)°, V = 4093(2) (?)3, Z = 4, Dc= 1. 77gcm-3, F(000) = 2176, μ(MoKα)=13.50cm-1, final R =0. 068 for 2835 observations. The molecular configuration is new and of approximate C, symmetry, and there are two C6H5COO bridging groups in the structure. The three Mo atoms form an isosceles triangle with three sides of 2. 567(3), 2. 576(3), and 2. 649(3)(?), where the two Mo-Mo bonds bridged by C6H5COO group are much shorter than that without. Something about the reactivity of Mo clusters is discussed.  相似文献   

12.
<正> Mr=1178.9, monoclinic, P21/n, a=16.570(2), b=12.370(1), c=20.007(2) A,β=99.97(1)°, V=4039.0A3, Z=4, Dx=1.938 Mgm-3, λ(MoKα)=0.7107A, μ(MoKα)=23.96 F(000)=2296, room temperature. Final R value=0.047 for 4387 unique observed reflections. It consists of neutral mono-oxo-capped trinuclear molybdenum cluster molecules with an average Mo-Mo bond length of 2.626(4)A and an average Mo-0 bond length of 2.036(2)8.  相似文献   

13.
Oxidizing the trimer V(3)(μ(3)-O)(O(2))(μ(2)-O(2)P(Bn)(2))(6)(H(2)O) in the presence of excess (t)BuOOH results in V(4)(μ(3)-O)(4)(μ(2)-O(2)P(Bn)(2))(4)(O(4)) and heating W(CO)(6) and bis(benzyl)phosphinic acid in 1:1 EtOH/THF at 120 °C produces W(4)(μ(3)-O)(4)(μ(2)-O(2)P(Bn)(2))(4)(O(4)).  相似文献   

14.
Reacting VO(acac)2 with six equivalents of dibenzylphosphinic acid in the presence of 4,4′-bipyridine or μ2-N1,N2-di(pyridin-4-yl)oxalamide leads to trimeric (V3(μ3-O)O2)(μ2-O2P(CH2C6H5)2)6(4,4′-bipyridine) or the hexamer [(V3(μ3-O)O2)(μ2-O2P(CH2C6H5)2)6]2(μ2-N1,N2-di(pyridin-4-yl)oxalamide). The complexes were characterized by spectroscopic (FTIR and 1H NMR spectroscopies), TGA, and by single crystal X-ray diffraction measurements. The structures consist of a planar central core where three vanadium ions are arranged in the form of a quasi-isosceles triangle and contain an interstitial O which is multiply bonded to one V and weakly interacting at different bond distances to the remaining two V ions.  相似文献   

15.
[Fe(3)(μ(3)-O)(μ-OAc)(6)(py)(3)][FeBr(4)](2)[py·H], complex (1), (OAc is acetate) was prepared from the reaction of FeBr(3) with pyridine in 1.2 molar aqueous HBr and 2.4 molar aqueous CH(3)COOH. Recrystallization of 1 in acetonitrile produced the [Fe(3)(μ(3)-O)(μ-OAc)(6)(py)(3)][FeBr(4)] complex (2). Both complexes were characterized by IR and (1)H NMR spectroscopies and their structures were studied using the single-crystal diffraction method. There is a lack of thorough characterization of the titled compounds in solution. Paramagnetic (1)H NMR is introduced as a good probe for the characterization of a family of titled compounds in solution when the L ligand coordinated to iron varies as: CH(3)OH, CH(3)CN, DMSO, H(2)O, py and acetone.  相似文献   

16.
The reactions of the heterometallic complexes (-H)Os3(-O2CC5H4FeCp)(CO)10 (1) and Fe{(-O2CC5H4)(-H)Os3(CO)10}2 (2) with CF3COOH, CF3SO3H, and AcCl were studied. The reaction of 1 with CF3COOH involves interaction with the Cp ligands, protonation of the O atom of the bridging carboxylate group, and oxidative degradation of the complex. At low concentrations, CF3SO3H protonates the O atom of the bridging carboxylate group, while at high concentrations, degradation of the complex takes place. The reaction of complex 2with either CF3COOH or low concentrations of CF3SO3H results in successive elimination of two [(-H)Os3(CO)10] cluster fragments due to protonation of the O atoms of the carboxylate groups. In the case of high CF3SO3H concentrations, the Os—Os bonds of both cluster fragments of 2 are also protonated to give the [Fe{(-O2CC5H4)(-H)2Os3(CO)10}2]2+ dication. The Friedel—Crafts acylation of 1 takes place only when a large excess of AcCl and AlCl3 is used to give two new complexes, (-H)Os3(-O2CC5H4FeC5H4C(O)CH3)(CO)10 and (-H)Os3(-O2CC5H3C(O)CH3FeCp)(CO)10 in a 2 : 1 ratio.  相似文献   

17.
The reaction of (μ-H)Os3μ-O2CC5H4Mn(CO)3(CO)10 with PPh3 in the presence of Me3NO gave mono- and disubstituted heterometallic complexes (μ-H)Os3μ-O2CC5H4Mn(CO)3(PPh3)(CO)9 and (μ-H)Os3μ-O2CC5H4Mn(CO)3 (PPh3)2(CO)8. Crystal structure determination was performed for three isomeric cluster complexes (μ-H)Os3μ-O2CC5H4Mn(CO)3(PPh3)2(CO)8, which are both geometrical and conformational isomers differing in color. The geometrical isomerism is due to the attachment of the PPh3 group at different vertices of the Os3 triangle relative to the O2CC5H4Mn(CO)3 bridging ligand. The conform ational isomerism implies that the molecules have the same arrangement of ligands and differ only in the values of bond angles between the planar fragments of the clusters.  相似文献   

18.
19.
The synthesis and crystal structure of the first example for hybrid Sn-Mo tetranuclear cubane-like cluster compound containing S/O mixed triple capping atom [Mo3(SnBr3)(μ 3-O)(μ 3-S)3(dtp)3(py)3]·(CH2Cl2) (A) (dtp=S2P(OC2H5)2) are reported. The compound is prepared by the reaction of [Mo3(μ 3-O)(μ-S)3(dtp)4·(H2O)] with SnBr 3 ? . The molecular structure of the cluster can be described as a [Mo3OS3] core with the SnBr 3 ? fragment linked to {Mo3} triangle by three (μ 3-S). Three Mo-Mo bond lengths are 2.616(2), 2.620(2), 2.628(2) Å, respectively, and the molecule has approximately C3v symmetry. There is no bonding between Sn and Mo atoms, however, the addition of SnBr 3 ? may cause electron transfer from Sn2+ to [Mo3OS3] core to result in the shortening of Mo-Mo bond distances. The compound crystallizes in the monoclinic space group P21/n with refined lattice parameters ofa=13.012(4),b=22.877(6),c=18.585(6) Å,β=96.34(3)°,V=5498(3)Å3, andZ=4. Full matrix refinement converged with final agreement factor ofR=0.054,R w=0.064.  相似文献   

20.
The new cubane cluster complex K6[Ta4(4-O)(3-Te)4(CN)12]·KOH·4H2O was prepared from a mixture of TaTe4 and KCN by the high-temperature synthesis followed by crystallization from aqueous solutions. The compound was characterized by cyclic voltammetry, X-ray diffraction analysis, and IR, Raman, and electronic spectroscopy. A comparative study of the clusters [M4(4-O)(3-Te)(CN)12]6– (M = Nb or Ta) containing the 4-O ligands was carried out. These clusters are the first molecular chalcogenide cubane complexes of Group V metals.  相似文献   

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