Synthesis and Structure of a La(Ⅲ) Complex of 1,10-Phenanthroline-2,9-dicarboxylate:a Three-dimensional Network via Hydrogen Bonding Interactions

A new La(Ⅲ) complex, {[La(L)(NO3)(H2O)3]·H2O}n (L = 1,10-phenanthroline- 2,9-dicarboxylate), has been synthesized and structurally determined by X-ray diffraction analysis. The complex crystallizes in the monoclinic system, space group P21/c with a = 7.7358(17), b = 8.1664(18), c = 28.271(6) , β = 95.184(4)°, V = 1778.6(7)3, Z = 4, C14H14LaN3O11, Mr = 539.19, Dc = 2.014 g/cm3, μ = 2.471 mm–1, F(000) = 1056, the final R = 0.0350 and wR = 0.0659. In this complex, each metal center adopts a ten-coordination geometry formed by two N atoms from a ligand L and eight O atoms from three H2O molecules, a nitrate ion and carboxylates of two ligands. Each ligand adopts a N2,O3-pentdentate coordination mode using two N and two O atoms chelating a La(III), and using another O atom of carboxylate to bridge another La(III) center resulting in a 1D helical chain molecule. Intermolecular strong O–H···O and weak C–H···O hydrogen bonds extend the 1D chain structure into a 3D supramolecular architecture.     

Thermodynamic Stability Research of Metal Complexes with a Tripodal Amide Ligand and Crystal Structure of its Cobalt（Ⅲ） Complex

A new Co（Ⅲ） complex with a tripodal amide ligand [CoL（N3）3] （L = N-acetyl- N＇,N＇-bis-[（2-pyridyl）methyl]-ethylenediamine） has been synthesized and characterized structurally by X-ray diffraction. It crystallizes in orthorhombic, space group Pnma with a = 9.2515（19）, b = 12.729（3）, c = 17.273（4） A, V = 2034.0（7） A3, C16H20CoN13O, Mr = 469.38, Dc = 1.533 g/cm3, μ（MoKα） = 0.884 mm^-1, F（000） = 968, Z = 4, the final R = 0.0392 and wR = 0.0818 for 2430 observed reflections. In the complex, the amide ligand L acts as a tridentate fashion and coordinates to the Co（Ⅲ） ion through three nitrogen atoms, while the other three positions of the Co（Ⅲ） center are occupied by three terminal azide anions. The complex is connected as a 1D chain structure by intermolecular hydrogen bonds between the uncoordinated amide groups. In order to investigate the coordination ability, thermodynamic stability of the ligand L with the first-series transition metal ions （Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ） and Zn（Ⅱ）） has been studied by potentiometric titration, and the results show that the order of their stability constants conforms to the Irving-Williams sequence.     

Synthesis,Crystal Structure and Antitumor Activity of a Na(Ⅰ) Coordination Polymer Based on 2-Propyl-4,5-imidazoledicarboxylic Acid and 1,10-Phenanthroline Ligands

A new Na(I) coordination polymer, [Na2(Hpimdc)(H2 pimdc)(phen)2]n(1), has been synthesized by the reaction of NaOH with 2-propyl-4,5-imidazoledicarboxylic acid(H3 pimdc)and 1,10-phenanthroline(phen). The Na(I) coordination polymer 1 was characterized by single-crystal X-ray diffraction analysis and elemental analysis. In 1, the bridged ligand H3 pimdc adopts two modes(singly deprotonated and doubly deprotonated) to coordinate with the Na(I) ion.The Na(1) ion is six-coordinated with three N atoms from a phen ligand and a H2 pimdc ligand,three O atoms from a Hpimdc ligand and two other different H2 pimdc ligands. The Na(2) ion is also six-coordinated with three N atoms from a phen ligand and a Hpimdc ligand, three O atoms from a H2 pimdc ligand and other two different Hpimdc ligands. Complex 1 exhibits a 1 D chain structure built up by μ-H2 pimdc-and μ-Hpimdc2-ligands. The antitumor activities of complex 1 against human SGC7901, A549 and H08910 cells have been tested.     

Synthesis and Crystal Structure of a Coordination Polymer [Zn（p-pdoa）（bbp）]n with a One-dimensional Helical Chain

The coordination polymer [Zn（p-pdoa）4（bbp）]n 1 （p-pdoa = p-phenylenedioxydiacetate dianion and bbp = 2,6-bis（benzimidazol-2-yl）pyridine） has been synthesized by hydrothermal method and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The title complex crystallizes in the triclinic system, space group P1^- with a = 7.8383（2）, b = 12.6610（4）, c = 13.1792（5）A, a = 84.433（2）,β = 74.2980（1）, γ = 87.4290（1）°, V = 1252.93（7）A^3, Z = 2, Dc = 1.593 g/cm^3,/z = 1.038 mm^-1, F（000） = 616, the final R = 0.0361 and wR = 0.1139. The Zn（Ⅱ） atom assumes a distorted trigonal bipyramidal geometry, involving two carboxyl O atoms from two different p-pdoa ligands and three N atoms from the bbp ligand. The Zn（Ⅱ） atom is alternately interlinked by p-pdoa ligands in a bismonodentate mode into a helical chain with a long pitch of 12.661 A and the adjacent Zn…Zn distance of 11.056 and 12.245 A. There exists a 2D supramolecular framework linked by π-π stacking （3.312 A） between adjacent benzimidazoles of bbp ligands and intermolecular hydrogen-bonding interactions between the uncoordinated carboxylate oxygen atoms （O（2）, 0（5）） and the uncoordinated imidazolyl N atoms （N…O distances 2.706 and 2.786 A）. There also exist two interlayer π-π stacking interactions of 3.299 A between adjacent central pyridines of bbp ligand and 3.176 A between the phenyl groups of p-pdoa ligand. Such π-π stacking interactions extend the two-dimensional layers into a 3D supramolecular network.     

Synthesis and Crystal Structure of a Novel 3D Inorganic-organic Hybrid Metallic Coordination Polymer, [Na2Cd（2,6-pyda）（N3）2（H2O）6]n

A novel coordination polymer [Na2Cd（2,6-pyda）（N3）2（H2O）6]n （2,6-H2pyda = 2,6- pyridinedicarboxylic acid） has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c, with a = 24.416（4）, b = 10.7638（17）, c = 6.9224（11） A^°, β= 106.124（2）A^°, V = 1747.7（5） A^°3, Mr = 515.64, De= 1.960 g/cm^3,μ = 1.365 mm^-1, F（000） = 1024, Z = 4, the final R = 0.0426 and wR = 0.1320. In the title complex, there exist two kinds of metal centers in the structure, cadmium ions and sodium ions. The Cd（Ⅱ） atom shows a distorted pentagonal-dipyramidal geometry defined by two O and one N atoms from one deprotonated pyda ligand and four N atoms from four μ-1,1,3 azido groups. The adjacent cadmium atoms are bridged via two μ-1,1,3 azido groups, along the c axis to afford an extended chain. There is also a 2D network which is comprised of binuclear subunits [NaE（H2O）6] connected by O atoms from coordinated water between the adjacent Cdn（pyda）n（Na）2n infinite chains. Furthermore, each cadmium atom is connected with four adjacent sodium atoms through the bridging N3- ligand in μ-1,3 patterns. Thus, the title complex exhibits a novel three-dimensional network structure.     

Synthesis,Crystal Structure,Fluorescent Property and DFT Study of a Novel 1D Polymer [Zn(HMICD)(bpy)]_n·2nH_2O

A new one-dimensional(1D) polymer, [Zn(HMIDC)(bpy)]_n·2n H_2O(1, H_3MIDC = 2-methyl-imidazole-4,5-dicarboxylic acid, bpy = 2,2?-bipyridine), has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, UV-vis spectrum and fluorescence measurements. Complex 1 crystallizes in orthorhombic system, space group Pbca with a = 14.404(3), b = 8.6900(17), c = 26.570(5) ?, V = 3325.8(11) ?~3, Dc = 1.700 g/cm~3, M_r = 425.70, Z = 8, F(000) = 1744, μ = 1.522 mm~(-1), the final R = 0.0421 and w R = 0.1018. The Zn(Ⅱ) ion is six-coordinated by O and N atoms from one HMIDC ligand, two O atoms from another HMIDC ligand and two N atoms from the bpy ligand. The HMIDC anion, which acts as a tetradentate ligand, chelates two Zn ions to form a one-dimensional(1D) zigzag chain structure. We analyzed the electronic structure and orbital energies of complex 1 by DFT methods, and the results are consistent with the UV-vis spectrum. And we also discussed the luminescent mechanism of complex 1 in detail.     

Synthesis and Crystal Structure of a New Oxovanadium（V） Multicomponent Complex with Acylhydrazone and Benzoylhydrazine

A new oxovanadium（V） complex with the mixed ligand of 2-oxopropionic acid benzoylhydrazone （C10H10N2O3） and benzoylhydrazine （C7H8N2O）, VO（C7H7N2O）（C10H9N2O3）, has been synthesized. Its structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to monoclinic system with space group P21/n and cell parameters： a=1.1136（4） nm, b=0.6217（2） nm, c=2.6038（9） nm, β=97.182（6）°, V= 1.7887（11） nm^3, Z=4, F（000）=836, Mr=407.28, Dc= 1.512 g/cm^3,μ （Mo Kα） =0.592 mm^-1, R1 =0.0445, wR2= 0.1203. Vanadium atom is 6-coordinated by carboxyl and carbonyl O atoms and N atom of one tridentate C10H10N2O3 to form two stable five-membered rings with the same edge, and the other coordinated atoms of N and O come from one bidentate benzoylhydrazine C7H8N2O. The title complex has a six-coordinated V center [VO（N2O3）] with a distorted octahedral arrangement. In the crystal lattice, there are hydrogen bonding interactions between two molecules.     

Synthesis,Crystal Structure and Fluorescent Property of a Lanthanum(Ⅲ) Complex Coordinated with Quinolinyloxy Acetamide Ligand

A novel lanthanum(Ⅲ) complex, [LaL2(NO3)3]·H2O(1) based on L(L = N-(naphthalene-1-yl)-2-(quinolin-8-yloxy)acetamide), was synthesized and characterized by X-ray diffraction. The crystal of 1 belongs to the monoclinic system, space group C2 c with Mr = 1017.69, a = 25.1438(17), b = 13.5950(9), c = 18.2349(12) A, β = 132.4980(10)°, V = 4595.8(5) A3, Z = 4, Dc = 1.471 Mg/m3, F(000) = 2056, μ = 1.004 mm-1, R = 0.0588 and wR = 0.1402. The central La(Ⅲ) ion is coordinated to four oxygen atoms, two nitrogen atoms from two independent acetamide ligands and six oxygen atoms from three nitrate anions, possessing a distorted icosahedron coordination geometry. In the crystal of 1, intermolecular N–H···O hydrogen bonds linked the molecules into chains along the c axis. In solid state and CH3 CN solution, complex 1 exhibits stronger fluorescent emission than the ligand L.     

Synthesis, Characterization and Crystal Structure of [Ni（S2P{O}OC6H4CH3-p）（dppv）]

O-（p-tolyl）dithiophosphato nickel complex [Ni（S2P{O}OC6HaCH3-p）（dppv）] has been synthesized by the treatment of （dppv）NiCl2 （dppv = Ph2PCH=CHPPh2） with （p-CH3C6HaO）2P{S}SH＇Et2NH in THF. The new complex was fully characterized by elemental analysis, IR, 1H NMR, 31p NMR spectroscopies and thermo-gravimetric analysis. The molecular structure of the complex was established by X-ray crystallography. The crystal crystallizes in monoclinic, space group P21/c with a = 9.2739（5）, b = 17.8803（8）, c = 20.1879（12） A, fl = 93.269（5）, V = 3342.1（3） A3, Z = 4, C33H29NiO2P3S2, Mr = 673.30, Dc = 1.338 g/cm3, F（000） = 1392 and #（MoKa） = 0.877 rnm-l. The final R = 0.0578 and wR = 0.1045 for 4138 observed reflections with 1 〉 20（/） and R = 0.1050 and wR = 0.1204 for all data. The Ni centre atom adopts a NiP2S2 square-planar geometry with two phosphorus atoms from the dppv ligand and two sulfur atoms from the O-（p-tolyl）dithiophosphate ligand. The most interesting structural feature of the title complex resides in its 1D helical chain structure constructing via intermolecular C-H＇＂O secondary interactions along the b-axis. The adjacent helical chains running in opposite directions are connected into a 1D double-stranded helical chain and further linked into a 2D supramolecular network by weak C-H.--C interaction.     

Antitumor Metallothiosemicarbazonate： Synthesis,Crystal Structure,Spectra and Antitumor Studies of Co（Ⅲ） Complex with Thiosemicarbazone Derivative of 2-Benzoylpyridine

The title complex [Co（L）2]Cl·4H2O I has been achieved via self-assembly by incorporating cobalt into 2-benzoylpyridine thiosemicarbazonate ligand, and characterized by elemental analysis, infrared spectra, mass spectra and single-crystal X-ray diffraction study. The crystal crystallizes in monoclinic, space group P2 1/n, with a = 10.227（3）, b = 17.363（4）, c = 17.459（4） A, β= 100.408（4）°, V= 3049.2（13） A^3, Z = 4, Mr = 677.08, Dc = 1.475 g/cm^3, μ（MoKα） = 0.834 mm^-1, F（000） = 1400, the final R = 0.0747 and wR = 0.0896 for 1663 observed reflections with I 〉 2σ（I）. The complex contains one six-coordinated cobalt ion connected by two thiosemicarbazone ligands which act as a tridentate ligand to coordinate with the center metal atoms via two pyridyl nitrogen atoms, two imine nitrogen atoms and two sulfur atoms giving rise to a mononuclear structure. Hydrogen bonds existing in the complex link the different components to stabilize the crystal structure. The antiturnor activity of the title complex was tested against A549 lung cancer cell line. Complex ! exhibits antitumor activity.     

Syntheses and Properties of Two Complexes Based on Keggin-type Polyoxometalate

Two unusual complexes [Cda（Do）4（H2O）2CI]（PW12O4O）＇2H2O （1） and [Aga（Do）6（PW12O40）][Ag（Do）2]2（PW12O4O）＇2H2O （2） were hydrothermally synthesized by the combination of two different metallic salts, Keggin-type polyoxometalate and 1,10-phen-5,6-dione （Do）, and characterized by elemental analyses, inductively coupled plasma analyses, infrared spectra, X-ray photoelectron spectroscopy, thermal gravimetry, photoluminescent spectra and single-crystal X-ray diffraction analyses. Crystal 1 is of monoclinic, space group P21/n with a = 12.383（3）, b = 18.326（4）, c = 16.437（3） A, β = 90.29（3）°, V = 3730.1（13） A3, Z = 2, CdzCasH32NsC1052PW12, Mr. = 4050.24, Dc = 3.604 g＇cm-3,μ（MoKa） = 19.145 mm1, F（000） = 3608, GOOF = 1.168, the final R = 0.0569 and wR = 0.0745 for 5715 observed reflections （1 〉 2σ（I））. Crystal 2 is of triclinic, space group Pi with a = 13.959（5）, b = 16.972（5）, c = 17.647（5）A, α = 85.970（5）, β = 81.353（5）, γ = 86.316（5）°, V = 4117（2） A3 Z = 1, Ag6C120H64N200102P2W24, Mr. = 8539.47, Dc = 3.444 g-cm-3,μ（MoKa） = 17.511 mm-1, F（000） = 3828, GOOF = 1.033, the final R = 0.0981 and wR = 0.1658 for 9906 observed reflections （I 〉 2σ（I））. Structural analyses show that complex 1 has a zero dimensional structure, which is further assembled into a one-dimensional ladder-like structure through hydrogen bonds. Complex 2 possesses a one-dimensional chain structure. Furthermore, solid-state luminescent spectra of complexes 1 and 2 indicate red and green fluorescent emission, respectively.     

Ion pairing, H-bonding, and π–π interactions in copper(II) complex-organo-networks derived from a proton-transfer compound of the 1,10-phenanthroline-2,9-dicarboxylic acid

The one-pot reaction between the novel proton transfer compound (pydaH₂)²⁺(phendc)²⁻, LH₂, and Cu(II) afforded the compounds (pydaH)₂[Cu(phendc)₂]·10H₂O, 1, and (pydaH)₂[Cu(phendc)(phendcH)]₂·5H₂O, 2, where pyda=2,6-diaminopyridine, and phendcH₂=1,10-phenanthroline-2,9-dicarboxylic acid. The single crystal X-ray diffraction analysis of 1 and 2 revealed that these are two novel self-assembled 3D Cu(II) complex-organo-networks, in which (pydaH)⁺ ions and [Cu(phendc)₂]²⁻ or complex units are held together by ion pairing, H-bonding, and π–π interactions. Magnetic measurements over the temperature range 1.8–310 K revealed no significant magnetic coupling between Cu(II) centers in 1 or 2.     

Solvothermal Synthesis of a 3D Luminescent Cadmium-organic Framework with msw Topological Net

A new cadmium-organic framework, [Cd2（TBDC）2（DMF）2（H2O）]n （1）, was synthesized by solvothermal reaction of rigid carboxylate ligand 2,3,5,6-tetramethyl-l,4-ben- zenedicarboxylate （H2TBDC） and cadmium nitrate and characterized by elemental analysis, infrared spectrum, thermal analysis, PXRD, single-crystal X-ray diffraction and photoluminescence in the solid state. Compound 1 crystallizes in orthorhombic, space group Pca21 with a = 21.487（6）, b = 7.790（2）, c = 20.666（6） A, C30H40Cd2N2O11, Mr = 829.44, V= 3459.3（16） A3, Z = 4, Dc = 1.593 g.cm-3,μ = 1.29 mm-1, F（000） = 1672, 2.7〈θ〈27.2°, λ（MoKa） = 0.71073 A, T= 293（2） K, the final R = 0.026, wR = 0.0548 and S = 1.027. X-ray diffraction analysis reveals that complex 1 possesses a 3D framework and exhibits rnsw net. Thus, the solid-state luminescent spectrum of 1 displays that the emission of cadmium（lI） complex shows a peak at 317 nm upon 250 nm excitation at room temperature.     

Synthesis,Crystal Structure and Biological Activity of a New 4,5-Diaryl-lH-imidazole Derivative

A new 4,5-diaryl-lH-imidazole was synthesized and characterized by 1H NMR, ESI-MS, elemental analysis and FT-IR. The crystal structure of the title compound （C19H16C12N202, Mr = 375.24） has been determined by single-crystal X-ray diffraction. Crystal parameters： mono- clinic system, space group P2/n, a = 14.349（3）, b = 8.7918（18）, c = 15.352（3） A, β = 108.56（3）°, V = 1836.1（6） A3, Z = 4, F（000） = 776, Dc = 1.357 g/cm3, p = 0.368 mm-1, the final R = 0.0502 and wR = 0.1066 for 2324 observed reflections with 1 〉 2 σ（/）. A total of 16117 reflections were collected, of which 3615 were independent （Rint = 0.0595）. The preliminary bioassay suggested that the title compound exhibits distinct effective inhibition on the proliferation of cancer cell lines.     

Synthesis of TiO2/ZnSn（OH）6 Hollow Nano-composite via a Simultaneous Crystallization-etching Route as Photocatalyst

We report the synthesis of TiO2/ZnSn（OH）6 as a novel nano-composite material via a simultaneous crystallization-etching route with cubic nano-ZnSn（OH）6 and TiF4 as the precursors. The structure, composition and morphology of the composite were characterized by XRD, EDS, FETEM and FESEM, which showed the prepared TiO2/ZnSn（OH）6 had a unique morphology of hollow cubic nano-ZnSn（OH）6 attached with rutile TiO2 nanoparticles. The results of photocatalytic activity measurement indicated the photocatalytic activity of the prepared composite was better than that of nano-ZnSn（OH）6. This study may be helpful for the design and fabrication of functional comoosite materials.     

Synthesis and Crystal Structure of a 1D Alternate Chain Polymer [Zn2（NBA）2（4,4′-bipy）]n

A one-dimensional zinc-containing coordination polymer, [Zn2（NBA）2（4,4′-bipy）]n （NBA = 3-nitrobenzoic acid, 4,4′-bipy = 4,4′-bipyrindine）, has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, IR and elemental analysis. The crystal structure is of monoclinic, space group C2/c with a = 24.6478（2）, b = 14.0964（3）, c = 11.4275（2）A, β=108.7870（10）°, V = 3758.89（11） ,A^3, C38H20N6O16Zn2, Mr = 947.34, Z = 4, De = 1.674 g/cm^3 μ= 1.363 mml, F（000） = 1912, R = 0.0720 and wR = 0.2277 for 2841 observed reflections （I 〉 2σ（I）. In this compound, NBA in syn-syn coordination mode bridges zinc centers into dimericzinctetracarboxylate [Zn2（COO）4] secondary building units （SBUs） which are linked through μ-4,4′-bpy affording 1D alternating chains. These adjacent chains are further stacked through intermolecular π...π interactions to form a 3D framework.     

Indexing Non-merohedrally Twinned Crystals by Bruker＇sAPEX2 and Agilent＇s CrysAlis~（PRO）, an Example of a Crystal Structure That Can Be Refined through Either the PLATONRoute or the ＇HKLF 5＇ Route,and, Simultaneous Data Collection of Two Crystals in a Two-in-one Run

The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis（diethyldicarbamato）nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [（3-formyl-4- hydroxyphenyl）methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5＇（based on a combined set of diffraction indices） and PLATON（based on one set of diffraction indices） routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{（E）-（4-aminophenyl）diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly.     

C2H2 Overtones Near 12300 cm^-1 Revisited with a Very Sensitive Cavity Ring-down Spectrometer

A cavity ring-down spectrometer （CRDS） is constructed with a single-mode continuous-wave Ti：Sapphire laser. It allows attaining a minimum detectable absorption of 1.8× 10^-10cm^-1. The spectrometer is applied to record the overtone spectrum of ^12C2H2 in the 12240- 12350 cm-1. Compared with the previous CRDS and intra-cavity laser absorption spectroscopy studies in the same region, the present measurement achieved better sensitivity and better precision as well. As a result, the ro-vibrational parameters of the high overtone bands of acetylene at 12290.12, 12311.82, and 12350.61 cm^-1 have been refined. The advantages of the present CRD spectrometer is also demonstrated by the newly observed and well characterized perturbation on the f component of the very weak band near 12289 cm^-1. The quantitative measurement capability of the spectrometer is verified with the measurement of the water lines and employed to give the absolute band intensities of those three acetylene bands.     

Acid-base equilibria of various oxidation states of aqua-ruthenium complexes with 1,10-phenanthroline-5,6-dione in aqueous media

Syntheses and pH dependent electrochemical properties of aqua-ruthenium(II) complexes, [Ru(trpy)(PDA-N,N')(OH2)](ClO4)2 ([1](ClO4)2) and [Ru(trpy)(PD-N,N')(OH2)](ClO4)2 ([2](ClO4)2) (trpy = 2,2':6',2'-terpyridine, PDA = 6-acetonyl-6-hydroxy-1,10-phenanthroline-5-one, PD = 1,10-phenanthroline-5,6-dione) are presented. Treatment of [Ru(trpy)(PD-N,N')Cl](PF6) with AgClO4 in a mixed solvent of acetone and H2O selectively produced the acetonyl-PD complex [1](ClO4)2, and the similar treatment in a mixed solvent of 2-methoxyethanol and H2O gave the PD complex [2](ClO4)2. The molecular structures of both complexes were determined by X-ray structural analysis. The proton dissociation constants of various oxidations state of [1]2+ and [2]2+ were evaluated by simulation of E(1/2) values of those redox potentials depending on pH. The simulation revealed that the acetonyl-PD complex [1]2+ underwent successive Ru(II)/Ru(III) and Ru(III)/Ru(IV) redox couples though the two redox reactions were not separated in the cyclic voltammograms. The redox behavior of [2]2+ in H2O is reasonably explained by not only the similar successive metal-centered redox reactions but also simultaneous two-electron quinone/catechol redox couple of the PD ligand including the contribution of hydration on a carbonyl carbon.     

Synthesis, Crystal Structure and Magnetic Properties of a Cobalt（II） Coordination Polymer with 4,4＇-（Propane-2,2-diyl）dibenzoate and 4,4 ＇-Bis（1-imidazolyl）biphenyl

A novel coordination polymer, {[Co（CBA）（BIMB）0.5]＇H20}n （1, H2CBA = 4,4＇- （propane-2,2-diyl）dibenzoic acid, and BIMB = 4,4＇-bis（1-imidazolyl）biphenyl）, has been hydro- thermally prepared and characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P2/c with a = 14.909（3）, b = 7.1963（15）, c = 24.592（5） A, β = 104.312（2）, V = 2556.5（9） A3, C26H23N2OsCo, Mr = 502.39, Dc = 1.305 g/cm3, F（000） = 1040,μ = 0.708 mm-1 and Z = 4. The final R= 0.0580 and wR = 0.1605 for 3228 observed reflections （1 〉 2a（I））. Single-crystal structure analysis shows that complex 1 exhibits a three-dimensional 2-fold interpenetrating pillared helical-layer open framework of a-Po topology based upon binuclear paddlewheel units. Moreover, its magnetic properties have also been investigated.