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1.
The complexes Pt(nb)3-n(P-iPr3)n (n=1, 2, nb=bicyclo[2.2.1]hept-2-ene), prepared in situ from Pt(nb)3, are useful reagents for addition of Pt(P-iPr3)n fragments to saturated triruthenium clusters. The complexes Ru3Pt(CO)11(P-iPr3)2 (1), Ru3Pt(-H)(3-3-MeCCHCMe)(CO)9(P-iPr3) (2), Ru3Pt(3-2-PhCCPh)(CO)10(P-iPr3) (3), Ru3Pt(-H)(4-N)(CO)10(P-iPr3) (4) and Ru3Pt(-H)(4-2-NO)(CO)10(P-iPr3) (5) have been prepared in this fashion. All complexes have been characterized spectroscopically and by single crystal X-ray determinations. Clusters 1–3 all have 60 cluster valence electrons (CVE) but exhibit differing metal skeletal geometries. Cluster 1 exhibits a planar-rhomboidal metal skeleton with 5 metal–metal bonds and with minor disorder in the metal atoms. Cluster 2 has a distorted tetrahedral metal arrangement, while cluster 3 has a butterfly framework (butterfly angle=118.93(2)°). Clusters 4 and 5 posseses 62 CVE and spiked triangular metal frameworks. Cluster 4 contains a 4-nitrido ligand, while cluster 5 has a highly unusual 4-2-nitrosyl ligand with a very long nitrosyl N–O distance of 1.366(5) Å.  相似文献   

2.
A highly efficient method for the synthesis of α-hydroxy phosphonates via lanthanide amides [(Me(3)Si)(2)N](3)Ln(μ-Cl)Li(THF)(3) catalyzed hydrophosphonylation of aromatic aldehydes was developed. The reactions produced the products in excellent yields in the presence of 0.1 mol % [(Me(3)Si)(2)N](3)La(μ-Cl)Li(THF)(3) at room temperature within 5 min. The existence of LiCl in the catalyst was a key factor affecting the catalytic activity. The mechanism for the process of high efficiency was proposed.  相似文献   

3.
<正> A new mixed-metal sulfido incomplete cubane cluster [(MoCuS3) (O) (μ-dtp) (PPh3)3] Cdtp = S2P (OC2H5)2] has been prepared by reaction of (NH4)2MoOS3 with Cu(dtp) (PPh3)2 in dimethylformamide solution. It crystallizes in the triclinic space group P1, a = 13.810(5), b = 19. 753(5), c=11. 719(4) A. α=99. 42(2), β=107. 24(3),γ=88. 05(3)°, V = 3012(2)A3, Dc = l. 51g/cm3and Z = 2. Final R=0. 046, Rw = 0. 056 for 7700 unique intensity data(I≥3σ(I)). The central unit [MoCu3S3]3+ can be described as a distorted incomplete cube with one missing corner. The Mo atom is tetrahedrally coordinated by three μ3-S atoms and one terminal O atom. Two Cu atoms are tetrahedrally coordinated whereas the third Cu atom has a highly distorted trigonal environment. The mean Mo - Cu bond length is 2. 752A. The Cu...Cu distances are in the range of 3. 200(1) -3. 740(1) A which are too long to form bonds.  相似文献   

4.
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   

5.
《Polyhedron》1999,18(6):811-815
Oxidative addition of H–R (H--Ph and H2) to trans-Ir(--Ph)(CO)(PPh3)2 (2) gives the initial products, cis, cis-Ir(H)(--Ph)2(CO)(PPh3)2 (3a) and cis, cis-Ir(H)2(--Ph)(CO)(PPh3)2 (3b), respectively. Both cis-bis(PPh3) complexes, 3a and 3b undergo isomerization to give the trans-bis(PPh3) complexes, trans, trans-Ir(H)(--Ph)2(CO)(PPh3)2 (4a) and cis, trans-Ir(H)2(--Ph)(CO)(PPh3)2 (4b). The isomerization, 3b4b is first order with respect to 3b with k1=6.37×10−4 s−1 at 25°C under N2 in CDCl3. The reaction rate (k1) seems independent of the concentration of H2. A large negative entropy of activation (ΔS=−24.9±5.7 cal deg−1 mol−1) and a relatively small enthalpy of activation (ΔH=14.5±3.3 kcal mol−1) were obtained in the temperature range 15∼35°C for the isomerization, 3b4b under 1 atm of H2.  相似文献   

6.
The reaction of CuX(2) (X(-) ≠ F(-)) salts with 1 equiv of 3-pyridyl-5-tert-butylpyrazole (HL) in basic methanol yields blue solids, from which disk complexes of the type [Cu(7)(μ(3)-OH)(4)(μ-OR)(2)(μ-L)(6)](2+) and/or the cubane [Cu(4)(μ(3)-OH)(4)(HL)(4)](4+) can be isolated by recrystallization under the appropriate conditions. Two of the disk complexes have been prepared in crystalline form: [Cu(7)(μ(3)-OH)(4)(μ-OCH(2)CF(3))(2)(μ-L)(6)][BF(4)](2) (2) and [Cu(7)(μ(3)-OH)(4)(μ-OCH(3))(2)(μ-L)(6)]Cl(2)·xCH(2)Cl(2) (3·xCH(2)Cl(2)). The molecular structures of both compounds as solvated crystals can be described as [Cu?Cu(6)(μ-OH)(4)(μ-OR)(2)(μ-L)(6)](2+) (R = CH(2)CF(3) or CH(3)) adducts. The [Cu(6)(μ-OH)(4)(μ-OR)(2)(μ-L)(6)] ring is constructed of six square-pyramidal Cu ions, linked by 1,2-pyrazolido bridges from the L(-) ligands and by basal, apical-bridging hydroxy or alkoxy groups, while the central Cu ion is bound to the four metallamacrocyclic hydroxy donors in a near-regular square-planar geometry. The L(-) ligands project above and below the metal ion core, forming two bowl-shaped cavities that are fully (R = CH(2)CF(3)) or partially (R = CH(3)) occupied by the alkoxy R substituents. Variable-temperature magnetic susceptibility measurements on 2 demonstrated antiferromagnetic interactions between the Cu ions, yielding a spin-frustrated S = (1)/(2) magnetic ground state that is fully populated below around 15 K. Electrospray ionization mass spectrometry, UV/vis/near-IR, and electron paramagnetic resonance measurements imply that the heptacopper(II) disk motif is robust in organic solvents.  相似文献   

7.
<正> C20H40Mo3NO8P3S10, Mr=1123.93, triclinic, P1,a=12.972(3), b=13.763(2), c= 14.515(7)A,α=66.22(3),β=101.72(3),γ=118.90(1)° , V= 2076(2) A3, Z=2,Dc=1.798 g.cm-3, MoKa radiation, final R= 0.040 and Rw=0.056 for 5645 observed reflections. The molecule contains three Mo atoms arranged in a triangle with one capping-S atom, three (μ-S) atoms, one (μ-EtCOO) ligand, one chelate ligand dtp on each Mo atom, and one terminal Py on atom Mo(1). The coordination of Mo atoms is of distorted octahedron.  相似文献   

8.
C60Ru(OCOCF3)(CO)(PPh3)配合物的合成及性能   总被引:1,自引:0,他引:1  
富勒烯;钌配合物;循环伏安法;C60Ru(OCOCF3)(CO)(PPh3)配合物的合成及性能  相似文献   

9.
娄太平  张乐  郭军兴 《化学学报》2010,68(6):466-470
研究了在不同温度下的NaNO3和AgNO3水溶液中Li1.3Ti1.7Al0.3(PO4)3和Na1.3Ti1.7Al0.3(PO4)3离子交换行为.实验表明Li1.3Ti1.7Al0.3(PO4)3和Na1.3Ti1.7Al0.3(PO4)3均显示出了高选择性与Na+和Ag+进行离子交换的特征,且对Ag+的选择性高于Na+.升高温度可显著提高Ag/Li和Ag/Na的交换反应速度.  相似文献   

10.
Quantum mechanical analysis reveals that carbonyl reduction of aldehydes and ketones by the imine-based reductant cis-[Os(III)(tpy)(Cl)(NH═CHCH(3))(NSAr)] (2), which is accessible by reduction of the analogous nitrile, occurs by hydride-proton transfer (HPT) involving both the imine and sulfilimido ligands. In carbonyl reduction, water or alcohol is necessary to significantly lower the barrier for proton shuttling between ligands. The -N(H)SAr group activates the carbonyl group through hydrogen bonding while the -NC(H)CH(3) ligand delivers the hydride.  相似文献   

11.
Abstract

The kinetics for isomerization of HRu333-EtSCCMeCMe)(CO)9 TO Ru3(μ-SEt) (μ33-CCMeCHMe)(CO)9, were determined. The overall process involves C[sbnd]H elimination, C[sbnd]S and Ru[sbnd]Ru bond cleavage and Ru2(μ-S) bond formation. Activation parameters were determined from the temperature dependence (ΔH? = 127(3) kJ/mol, ΔS?= 56(11) J/mol-K) and from the pressure dependence (0[sbnd]207 MPa, ΔV? 0 +12.7(1.1) cm3/mol, Δβ? = +0.037(0.012) cm3/(mol-MPa)) of the rate constant. The data are consistent with an intramolecular reaction involving significant metal-metal or carbon-sulfur bond cleavage in the transition state. The activation volume is too large to be accommodated by C[sbnd]H elimination alone and CO dissociation is not involved.  相似文献   

12.
β-二酮络合物已获得广泛而深入的研究,Ce(Ⅳ)的β-二酮类络合物的研究也有报导[1-3].但是,关于Ce(Ⅳ)的β-二酮与其它混合配体络合物的研究至今未见报导.我们以(NH4)2Ce(NO3)6为起始物质,经由双-(三苯基氧化膦)硝酸铈(Ⅳ)中间络合物在混合溶剂中与DBM反应制得该化合物.通过紫外、红外光谱以及1HNMR谱等研究,对该络合物的性质进行了讨论.  相似文献   

13.
A novel strawberry-like organic-inorganic hybrid, {Na(H(2)O)(3)[Lu(pydc)(H(2)O)(3)](3)}[SiW(12)O(40)]·26.5H(2)O (H(2)pydc = pyridine-2,6-dicarboxylate) containing an intriguing trinuclear lutetium cluster {Na(H(2)O)(3)[Lu(pydc)(H(2)O)(3)](3)}(4+) has been synthesized and its luminescent properties, IR, UV, TG, PXRD analyses and single crystal X-ray diffraction were investigated.  相似文献   

14.
In recent years the chemistry of mono- or hetero-binuclear complexes containing metal-S(C) bonding modes is a very active field of research. Many useful applications of this kind of complexes have been exploited, such as industrial catalytic hydrodesulfurization (HDS)1,2 and transition metals mediated organic synthesis3-5. In this paper we report that the reduction and subsequent protonation of hetero-binuclear complex [MnRe(CO)6(-S2CPPri3)] occur with cleavage of metal-metal bond and o…  相似文献   

15.
The mononuclear manganese complex Mn(phen)(CF3COO)(H2O)3(NO3 (C14H14O8N3F3Mn) has been synthesized, where phen = 1,10-phenanthroline. The molecular and crystal structures were determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 8.8550(3), b = 10.6529(3), c = 19.8763(2) A, β = 97.762(2)o, V = 1857.78(8) A3, Z = 4, Mr = 464.22, Dc = 1.660 g/cm3, μ = 0.789 mm-1, F(000) = 940, T = 293(2) K, R = 0.0764 and wR = 0.2441 for 1995 observed reflections with I > 2σ(I). In the crystal the manganese atom is six-coordinated by two chelated nitrogen atoms from phenanthroline, three oxygen atoms from water molecules and one oxygen atom from trifluoroacetate, completing an octahedral geometry.  相似文献   

16.
1 INTRODUCTION Schiff bases and their metal complexes are useful reagents in organic synthesis[1], and they have exhi- bited some biological activities as anticancer and antitumor drugs[2]. The crystal structures and physi- cal and chemical properties of many Schiff bases and their transition metals complexes have been re- ported[3~5]. Further interest in the coordination che- mistry of nickel(II) arises from the role of these complexes in several catalytic reactions, such as electrocat…  相似文献   

17.
<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   

18.
Dinuclear non-heme iron clusters containing oxo, hydroxo, or carboxylato bridges are found in a number of enzymes involved in O(2) metabolism such as methane monooxygenase, ribonucleotide reductase, and fatty acid desaturases. Efforts to model structural and/or functional features of the protein-bound clusters have prompted the preparation and study of complexes that contain Fe(micro-O(H))(2)Fe cores. Here we report the structures and spectroscopic properties of a family of diiron complexes with the same tetradentate N4 ligand in one ligand topology, namely [(alpha-BPMCN)(2)Fe(II)(2)(micro-OH)(2)](CF(3)SO(3))(2) (1), [(alpha-BPMCN)(2)Fe(II)Fe(III)(micro-OH)(2)](CF(3)SO(3))(3) (2), and [(alpha-BPMCN)(2)Fe(III)(2)(micro-O)(micro-OH)](CF(3)SO(3))(3) (3) (BPMCN = N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)-trans-1,2-diaminocyclohexane). Stepwise one-electron oxidations of 1 to 2 and then to 3 demonstrate the versatility of the Fe(micro-O(H))(2)Fe diamond core to support a number of oxidation states with little structural rearrangement. Insight into the electronic structure of 1, 2', and 3 has been obtained from a detailed M?ssbauer investigation (2' differs from 2 in having a different complement of counterions). Mixed-valence complex 2' is ferromagnetically coupled, with J = -15 +/- 5 cm(-)(1) (H = JS(1).S(2)). For the S = (9)/(2) ground multiplet we have determined the zero-field splitting parameter, D(9/2) = -1.5 +/- 0.1 cm(-)(1), and the hyperfine parameters of the ferric and ferrous sites. For T < 12 K, the S = (9)/(2) multiplet has uncommon relaxation behavior. Thus, M(S) = -(9)/(2) <--> M(S) = +(9)/(2) ground state transition is slow while deltaM(S) = +/-1 transitions between equally signed M(S) levels are fast on the time scale of M?ssbauer spectroscopy. Below 100 K, complex 2' is trapped in the Fe(1)(III)Fe(2)(II) ground state; above this temperature, it exhibits thermally assisted electron hopping into the state Fe(1)(II)Fe(2)(III). The temperature dependence of the isomer shifts was corrected for second-order Doppler shift, obtained from the study of diferrous 1. The resultant true shifts were analyzed in a two-state hopping model. The diferric complex 3 is antiferromagnetically coupled with J = 90 +/- 15 cm(-)(1), estimated from a variable-temperature M?ssbauer analysis.  相似文献   

19.
The trinuclear osmium carbonyl cluster, [Os3(CO)10(MeCN)2], is allowed to react with 1 equiv. of [IrCp1Cl2]2 (Cp1 = pentamethylcyclopentadiene) in refluxing dichloromethane to give two new osmium–iridium mixed-metal clusters, [Os3Ir2(Cp1)2(μ-OH)(μ-CO)2(CO)8Cl] (1) and [Os3IrCp1(μ-OH)(CO)10Cl] (2), in moderate yields. In the presence of a pyridyl ligand, [C5H3N(NH2)Br], however, the products isolated are different. Two osmium–iridium clusters with different coordination modes of the pyridyl ligand are afforded, [Os3IrCp1(μ-H)(μ-Cl)(η33-C5H2N(NH2)Br)(CO)9] (3) and [Os3IrCp1(μ-Cl)223-C5H3N(NH)Br)(CO)7] (4). All of the new compounds are characterized by conventional spectroscopic methods, and their structures are determined by single-crystal X-ray diffraction analysis.  相似文献   

20.
1 INTRODUCTION The manganese(II) ion is a biologically essential element. Knowledge of its importance is increasing as more and more enzymes are found to contain manganese ions at the active center[1, 2]. The X-ray crystallographic structures of a consi…  相似文献   

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