SYNTHESIS AND STRUCTURE OF AN ASYMMETRIC TRICOBALT COMPOUND Co_3(o-HOC_6H_4S)_2(o-OC_6H_4S)_2(PEt_3)_3

Compound Co_3(o-HOC_6H_4S)_2(o-OC_6H_4S)_2(PEt_3)_3 was obtained by reaction of CoCl_2,o-HOC_6H_4SH(H_2mD)and PEt_3 in ethanol in the presence of NaOCH_3.The three Co atoms aretriangularly arranged and asymmetrically bridged by four S and one O atoms from the fourH_2mp ligands and terminally ligated by one O and three P atoms.Two free hydroxyl groupsform two internal hydrogen bonds with adjacent oxo donor atoms.     

Hydrothermal Synthesis,Crystal Structure and Electrochemical Properties of the Copper(II) Complex [Cu_4O_4(phen)_4(ClC_6H_4COO)_2(H_2O)_2]·(H_2O)_3

1 INTRODUCTION As we all know, copper is a necessary trace element for human body. For example, a large number of bi- nuclear or multi-nuclear transition metallic complex- es exist in active centers of some metalloprotein[1]. In the 1960’s, Bertand and Bock et al[2] reported the first tetra-nuclear copper complex with Cu4O3 unit. In 1996, a cyclo-tetranucleate complex bridged by pyridine was synthesized by Zhang Hua etc[3]. In 1999, Tan Xiangshi and coworkers[4] presented a cubic tet…     

[Co_3(1,2-S2C6H4)_3(PPh_3)_3]+, A basic triangle unit of some polynuclear molecules

[Co3(1,2-S2C6H4)3(PPh3)3][CoBr3(DMF)].sol (1, sol=CHCl3,O(C2H5)2,H2O) was obtained from the reaction of CoBr(PPh3)3 with Na2(S2C6H4) in chloroform. The Co3 core in the cation of 1 exhibits a metal-metal bonded isosceles triangle, in which the two longer Co-Co bonds are both bridged by S2C6H4 ligands on two sides of the triangle plane respectively, while the bottom short Co-Co bond is bridged by the third bidentate S2C6H4 ligand. A series of polynu-clear cobalt cluster compounds with phosphine, thiolate and/or sulphur ligands were prepared by low oxidation state Co+ with thiolates in organic solvents. These tri-, tetra-, hexa-, heptanuclear cluster compounds 1-8 with various types of crystal structures can be viewed as the condensed polynuclear cobalt complexes that the cobalt atom frameworks with sulphur bridged were built through the small triangular units of [Co3S3nL3] (n=1,2) with or without [CoL] (L=PR3, Br, Cl, 5-C5H5) fragments.     

Synthesis, Structure and Properties of (n-Bu_4N)_3[Mo_6O_18NNAr(NO_2)_2]

The title compound was synthesized and characterized by means of elemental analysis, IR, DTA-TG and UV. Its single crystal structure was solved by using direct methods. The compound crystallizes in the orthorhombic space group Pmc(?) with lattice parameters: a = 1. 7261(2), b=l. 7537(3), c=2. 4258(3) nm. V=7. 34220 nm3, F(000) = 3648, Z = 4. The structure was refined to conventional discrepancy factors of R=0. 060 for 3176 observed reflections [Ⅰ>3σ/(Ⅰ)]. The anion represents a modification of the well-known [Mo6O19]2- anion, in which a single terminal oxo group is replaced by a 2,4-dinitrophenyl hydrazine ligand while the structure integrity of the hexanuclear framework is maintained.     

HYDROFORMYLATION OF 1-HEXENE WITH Rh_4(CO)_(12) AND [Rh(CO)_2Cl]_2

The hydroformylation of hexene-1 catalyzed by Rh_4 (CO)_12 and 〔Rh(CO)_2Cl〕_2 andthe effects of solvents (benzene, n-heptane and THF) and PPh_3 on the activity andselectivity of the catalysts were studied.The results indicated that the activity of Rh_4(CO)_(12) decreased with increasing solventpolarity and it did not change appreciably with addition of PPh_3 when the molar ratioPPh_3/Rh_4(CO)_(12)≤4. Thc activity of Rh_4(CO)_(12) was over twice as large as that of〔Rh(CO)_2Cl〕_2 when calculated according to the number of moles of rhodium clusters inbenzene without PPh_3, but the activities of both Rh_4(CO)_(12) and 〔Rh(CO)_2Cl〕_2 wereabout the same when calculated according to the number of rhodium atoms. It is suggestedthat the clusters probably dissociated into the similar active rhodium mononuclear speciesunder the reaction conditions and the species formed a cluster similar to Rh_4(CO)_(12) againwhen the conditions were reduced to the ambient temperature and pressure.     

HETERONUCLEAR COMPLEX CONTAINING COPPER-LANTHANIDE ARRAYS: THE SYNTHESIS AND CRYSTAL STRUCTURE OF Ln_2Cu_4L_8 (HL)_4(OH)_2(CIO_4)_4(H_2O)_(10)·2CH_3COCH_3 (Ln = Tb (1), Y (2); HL = 2-Pyridone C_5H_5NO)

Reaction of 2-pyridone, copper acetate and terbium(or yttrium) perchlorate in acetone with the moleratio 6: 2: 1 results in the formation of heteronuclear complex Ln_2Cu_4L_8 (HL)_4 (OH)_2 (ClO_4)_4 (H_20)_(10)2CH_3COCH_3(Ln = Tb (1), Y (2)). By recrystallizing (1) in CHCl_3 single crystals were obtained and thestructure was determined by four-circle diffractometer. Data showed that the crystal is in space groupC2/m with a=27. 454(9)A, b=13, 608A, c=30. 556(11)A, β=99. 89(3)°, v=11245. 7(7. 5)A~3. Thestructure was solved by a combination of Patterson method and Fourier technique. The final R value is0. 103. In the structure, four copper and two terbium ions are bridged by 2-pyridone anions to form anessentially octahedral Cu_4Tb_2 core. The terbium atoms are each eight-coordinate and the copper atomsare five-coordinate.     

RESEARCH ON TRINUCLEAR MOLYBDENUM CLUSTER COMPOUNDS——CRYSTAL AND MOLECULAR STRUCTURE OF (C_5H_7S_2)_3[Mo_3(μ_3-S)(μ_2-S_2)_3Cl_7]

The space group of the title crystal is Pnam. The unit cell parameters are: a=17.226(4), b=14.306(7), c=15.074(4); z=4, Dobs=2.03g·cm~(-3), D_(calc)=2.063g·cm~(-3). The crystal structure was solved by the heavy atom method and refined by the full-matrix least-squares until the final conventional discrepancy factor was reduced to 0.068. The results of the investigation show that the crystal consists of trinuclear Mo cluster anions [Mo_3(μ_3-S)(μ_2-S_2)_3Cl_7]~(3-) together with planar (C_5H_7S_2)~ monocations, surrounding the cluster anions. In the cluster anion three Mo atoms, forming a nearly equilateral triangle (2.755(1), 2.755(1), 2.743(1)), are bound by a μ_3-S bridging atom, while each pair of Mo atoms is bridged further by a μ_2-S_2 ligand. Besides, each Mo atom is coordinated to two terminal Cl atoms, so that the coordination sphere of each Mo atom approaches closely a pentagonal bipyramid. In addition, a single Gl atom, not at all involved in the coordination spheres of the three Mo atom     

RESEARCH ON TRINUCLEAR MOLYBDENUM CLUSTER COMPOUNDS——CRYSTAL AND MOLECULAR STRUCTURES OF (Et_4N)_2[Mo_3(μ_3-O)(μ_2-Cl)_3(Oac)_2Cl_5]

The title compound forms black crystals shaped like pseudo-octahedrons, which belong to the orthorhombic system The space group is Pna 2_1 with unit cell parametrs of a=17.815(1), b=16.629(2), c=12.003(1), and with Z=4, D_(obs)=1.80g·cm~(-3), and D_(calc)=1.804g·cm~(-3). The crystal structure was solved by the heavy atom method and refiened by fullmatrix least-squares to a final conventional R factor of 0.048 for 2584 unique reflections with I≥σ(Ⅰ). The investigation confirms that the crystal structure consists of tetraethylammonium cations and trinuclear Mo cluster anions. The anion is a μ_3-O monocapped trinuclear cluster with an average Mo-Mo bond length of 2.60 (2). On the side of the Mo_3 triangular plane opposite to the μ_3-O atom, each two Mo atoms are bridged by a Cl atom with the result that these seven atoms (3 Me, 1 O and 3 Cl atoms)form an apex-deficient quasicubane configuration. In addition, each Mo atom is coordinated to three additional atoms resulting in a pseudo-octahedral geome     

Synthesis and Structural Characterization of Bis(2,2''''-bpy)bis(azide)cobalt(III) nitrate dihydrate

1 INTRODUCTION The research on azide-bridged transition metal complexes has attracted great interest in the past decade due to their magnetic properties and potential applications[1~2]. A number of azide- bridged complexes with the end-to-end coordination mode affording antiferromagnetic exchange interactions and the end-on coordination mode showing ferromagnetic exchange interactions have been reported in recent years[3]. In the synthesis of azide bridged cobalt complexes, it was found …     

Molecular structure of [(trien)Zn(im)Zn(trien)](ClO_4)_3 complex and ESR spectra of its single-crystal doped with [(trien)Cu(im)Zn(trien)l(ClO_4)_3 complex

The crystal structure of the title complex was measured, in which the two zinc atoms with coordination polyhedron of distorted tetragonal pyramid (TP) are bridged by an imidazolate in the apical position of the TP forming a dimer. The isomorphous [(trien)Cu(im)Zn(trien)](ClO4)3·H2O complex was doped in the title complex and the recorded single-crystal ESR spectra by fitting gave two sets of the principal values of g and A tensors, which were assigned to the physically distinct sites of the two magnetically equivalent molecules in the unit cell. Lattice distortion at the Cu(II) ion sites and the bonding parameters of Cu(II) ions are further calculated, and the bonding nature of Cu(II) ions is discussed.     

Synthesis and Crystal Structure of Ni_3(admt)_6(NCS)_6·C_2H_5OH·2H_2O

1　INTRODUCTIONCoordination compounds with 1 ,2 ,4 triazole as a ligand have interesting fea tures,notonly because ofthe very interesting magnetic propertiesofthese complex es,but also because ofrich modes ofcoordination〔1〕.Particularly,the coordinationbehavioroftriazoletowardsa numberoftransition metalthiocyanatesshowsremark abledifferences〔2 - 6〕.On unsubstitution at N4 ,thetriazole ring hasmonodentate,1 ,2 and 2 ,4 bridging forms.These three modes were all observed in the Ni( II)…     

CRYSTAL STRUCTURE OF A LINEAR TETRANUCLEAR Mo-Fe-S CLUSTER, (Et_4N)_4C(MoS_4)_2Fe_2S_2D·(CH_3OH)_2

<正> C_34H_88O_2N_4Mo_2Fe_2S_10, Mt= 1209. 25,monoclinic, P2_1/a,a= 17. 722 (7) ,b= 11. 857(5),c= 13. 743(5) A .β= 112. 29 (3)°, V= 2672. 0A3,Z = 2,Dc = 1. 503 g·cm-33,μ(Moka) = 14. 0 cm-1,T=193 K. Final R=0. 045 for 1943 observed reflections (I≥3σ(I)). In the anion [(MoS4)_2Fe2S2]4- ,the two Fe atoms, each attached with a chelating MoS42- unit, are bridged by two sulfur atoms. The metal atoms are arranged in a linear fashion with Mo-Fe-Fe angle of 179. 1(1)°, and Fe-Fe and Fe-Mo distances of 2. 746(2) and 2. 801(2) A, respectively. The long Fe-S distances (average 2. 246A) in Fe2S2 ring could be a result of the hydrogen-bonding interaction between the sulfur atom and the methanolic hydrogen atom.     

配合物(ArO)2Yb(NPh2)2K(THF)4(Ar=C6H2-t-Bu3-2,4,6)的合成、分子结构和催化行为

Reaction of anhydrous YbC13 with 2 equiv, of sodium 2,4,6-tri-tert-butylphenoxide (ArONa, Ar=C6H2-t-Bu3-2,4,6) and 2 equiv, of potassium diphenyl amide in THF afforded the first bis(aryloxo) amido-lanthanide complex of (ArO)2Yb(NPh2)2K(THF)4 (1). In 1, the ytterbium and potassium were bridged via diphenyl amido ligands.The ytterbium metal center was coordinated to two oxygen atoms of aryloxide ligands and two nitrogen atoms of diphenyl amido ligands in a conventional distorted tetrahedral fashion, while the potassium interacted in η^2-fashion with two phenyl rings of the diphenyl amido ligands besides four THF molecules. 1 displayed moderate catalytic activities for the polymerization of methyl methacrylate and acrylonitrile.     

CRYSTAL AND MOLECULAR STRUCTURE OF MOLYBDENUM COM-PLEX MoO_2Cl_2(C_4H_3OCOOH)_2

<正> The crystal and molecular structure of the title compound was determined by single crystal X-ray diffraction method. The complex crystallizes in the mono-clinic space group P21/n with a = 10. 306 ( 3) , b = 10. 161 (2), c = 14. 798 ( 4) A . β= 108. 52(2)°, V= 1469. 4(6)A3,Z= 4. The structure was solved by direct methods. Least-squares refinement converged to a final value of R = 0. 043 and Rw= 0. 040 for 1237 reflections. The molybdenum (Ⅵ) ion is bonded to two chlorine atoms, two oxo atoms and two oxygen atoms from two monodentately and weakly coordinated carboxyl groups of molecules C4H3OCOOH, forming a octahedron. The Mo-O distances are in the range 1. 66 - 2. 39A ,the Mo-Cl distances fall in the range 2. 33-2. 34A.     

THE CRYSTAL AND MOLECULAR STRUCTURE OF (QH)_3[Mo_2O_4(■-COO)(NCS)_4]·H_20 AND (QH)_3[Mo_2O_4(CH_30H)(NCS)_5]

<正> INTRODUCTION. In the reported crystal structures of di(μ-X)(X=O,S)-bridged oxodimolybdates (Ⅴ), the local, symmetric array of donor atoms linked to the Mo atoms is well known. The title compounds (QH)_3[Mo_2O_4(COO)-(NCS)_4]-H_2O(Ⅰ) and (QH)_3[Mo_2O_4(CH_3OH)(NCS)_5](Ⅱ), in which the environments     

STUDY ON THE STRUCTURE AND SPECTRA OF BINUCLEAR BRIDGED COMPLEX μ-4,4-bipy [VO(acac)_2]_2

The synthesis and ~1H NMR, ESR, IR, UV spectra of binuclear bridged complex μ-4,4-bipy[VO-(acac)_2]_2 are reported in this paper. The structure of the complex is discussed using measured spectral parameters.It is deemed that 4,4-bipy as a bridge passing through its two N atoms combined respectively with two V atoms at its sixth position, forming a binuclear bridged complex.The spectra are explained satisfactorily and coefficients of molecular orbitals,β_1,β_2 and 8_m,are calculated from the results of ESR and UV etc.     

RESEARCH ON TRINUCLEAR MOLYBDENUM CLUSTER COMPOUNDS——CRYSTAL AND MOLECULAR STRUCTURE OF (Et_4N)_2[Mo_3(μ_3-O)(μ_3-Cl)(μ_2-Cl)_3Cl_6]·EtOH

The title crystal belongs to the monoclinic system. The space group is P2_1/c with unit cell parameters: a=11.379(3), b=20.766(2), c=14.487(3), β=91.49(2)°, V=3519(2)~3Z=4, D_c=1.819g.cm~(-3), D_0=1.81g.cm~(-3). The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the full-matrix least-squares to a final R factor of 0.040 based on 3261 unique reflections with intensities I≥3σ(I). The structure consists of two sots of tetraethylammonium cations and trinuclear Me cluster anions. In the cluster anion the three Mo atoms form an isosceles triangle with Mo-Mo distances of 2.601(1), 2.608(1), 2.642(1), respectively, showing a strong bonding interaction between the metal atoms. One μ_3-O atom and one μ_3-Cl atom are situated above and below the triangle respectively, binding the three Me atoms to form a triangular bipyramidal cluster core. Each pair of Mo atoms is bridged further by a μ_2-Cl atom situated on the Mo_3 triangular plane. In addition, each     

EPR AND ELECTRONIC STRUCTURE OF Mo(V) COMPLEX Mo_2O_3(S_2CNEt_2)_4

<正> INTRODUCTION. Particular interest of some chemists has directed to the chemistry of molybdenum, as the oxidation states of molybdenum (-2～+6) are interesting and Mo atom in various forms usually is contained in the active site of enzymes or catalysts.     

Hydrothermal Synthesis and Crystal Structure of a Bivanadyl Capped Keggin Polyoxomet alate[Zn(2,2''''-bpy)_2(H_2O)]_2[HPMo_(12)O_(40)(VO)_2]

1 INTRODUCTION The design and synthesis of organic-inorganic hy-brid compounds are of great interest owing to theirextensive theoretical and practical applications in ca-talysis, medicine, analytical chemistry, nanotechno-logy, electrochromism, magnetism and photochemis-try[1～5]. In heteropolyoxometalate chemistry, a newadvance is the decoration of polyoxoanions with va-rious organic and transition metal complex moieties.In contrast to a large number of known organic andtransition-metal-s…     

SYNTHESES AND CRYSTAL STRUCTURES OF (Et_4N)_2(Fe_2Se_2(SPh)_4) AND (Et_4N)_2(Fe_4Se_4Cl_4)

<正> Since the discovery of iron-sulfur proteins , a number of analogous compounds of the active sites of iron-sulfur proteins has been synthesized and characterized . Due to the similarity between sulfur and selenium, some selenoproteins with similar active site as iron-sulfur proteins were found . We have synthesized a series of iron-selenium compounds in correlative study with the iron-sulfur compounds. In this paper, we will discuss the syntheses and crystal stuctures of the title compounds. The spectroscopic properties of these compounds have been under investigation.