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1.
以Fe( ClO4)2·6H2O和N,N′,N″,N′″-四(2-吡啶甲基)-1,4,8,11-四氮杂环十四烷(tpmc)为原料,采用溶液界面扩散法,在二氯甲烷与乙醇两相溶剂的界面上制得Fe(Ⅱ)的双核配合物[Fe2 (μ2-OH)(C34H44N8)](ClO4)3·EtOH(1),其结构经X-射线单晶衍射表征.1属正交晶系,Pbcm空间群,晶胞参数a=11.652(2)(A),b=17.505(4)(A),c=22.256(5)(A),α=β=γ=90°,V=453 9.7(16)(A)3,Z=4,Dc =1.519 g·cm-3,μ=0.887 mm-1,F(000) =2 152,R1 =0.058 3,ωR2 =0.175 8.1中的Fe(Ⅱ)分别与外向型配体tpmc的十四元环上的两个氮原子,两个吡啶环上的氮原子和μ2-OH上的氧原子配位,形成一个畸变的三角双锥几何构型.连接两个Fe(Ⅱ)核中心的μ2-OH氧桥以及分子内和分子间的氢键缔合作用,增强了晶体结构的稳定性.  相似文献   

2.
3.
Two new MnII and FeII complexes with 4′-(4-pyridyl)-2,2′ : 6′,2″-terpyridine (pyterpy), [Mn(pyterpy)(MeOH)2(OAc)](ClO4) (1) and [Fe(pyterpy)2](SCN)2 · MeOH (2) have been synthesized and characterized by CHN elemental analysis, IR spectroscopy, and structurally analyzed by single-crystal X-ray diffraction. The thermal stabilities of these compounds were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The potentially tetradentate pyterpy ligand is a tridentate donor to both Mn(II) and Fe(II). The non-coordinated pyridyl interacts via O–H ··· N and C–H ··· N hydrogen bonds with adjacent molecules in 1 and 2, respectively, to form inversion symmetric dimers. Compound 1 is further extended into infinite hydrogen bonded chains via pairs of O–H ··· Oacetate hydrogen bonds.  相似文献   

4.
A new family of tetranuclear nickel cube complexes [Ni(4)L(4)(solv)(4)] (1, solv = MeOH; 2, solv = H(2)O; H(2)L = pyrazole-based tridentate {ONO} ligand) has been studied in detail, in particular by X-ray diffraction and superconducting quantum interference device (SQUID) magnetometry. Different solvates 1·H(2)O, 2·4C(3)H(6)O, 2·CH(2)Cl(2), and 2·H(2)O were obtained in crystalline form. Only small structural variations were found for the Ni-O-Ni angles of the [Ni(4)O(4)] cores of those compounds, but these slight variations have dramatic consequences for the magnetic properties. [Ni(4)L(4)(MeOH)(4)]·H(2)O (1·H(2)O) and [Ni(4)L(4)(H(2)O)(4)]·H(2)O (2·H(2)O) can be reversibly interconverted in the solid state by exposure to the respective solvent, MeOH or H(2)O, and this goes along with a switching of the spin ground state from magnetic (S(T) = 4) to diamagnetic (S(T) = 0). Likewise the (irreversible) loss of lattice solvent in [Ni(4)L(4)(H(2)O)(4)]·4C(3)H(6)O (2·4C(3)H(6)O) to give 2·2C(3)H(6)O changes the ground state from S(T) = 4 to S(T) = 0. In view of these dramatic solvatomagnetic effects for the present [Ni(4)L(4)(solv)(4)] complexes, which occur upon extrusion of lattice solvent or facile exchange of coordinated solvent molecules while keeping the robust [Ni(4)O(4)] core intact, a note of care is issued: whenever magnetic data are obtained for powdered material or for crystals that easily loose lattice solvent molecules, the magnetic properties may not necessarily reflect the situation observed in the corresponding single crystal diffraction study. Finally, a thorough analysis of the present series of complexes as well as other {Ni(4)(μ(3)-OR)(4)} cubes reported in the literature confirms that a correlation between the (Ni-O-Ni)(av) bond angle and J in [Ni(4)O(4)] cubane complexes does indeed exist.  相似文献   

5.
6.
The [Cu(Bcegly)(Im)](ClO4) · H2O aminocarboxylate, where HBcegly is N,N-bis(2-carbamoyl-ethyl)aminoacetic acid and Im is imidazole, is studied by X-ray diffraction. The polyhedron of the Cu atom is an asymmetrically elongated tetragonal bipyramid (4 + 1 + 1), whose equatorial plane is composed of two oxygen atoms (average Cu-O, 1.952 ?) and a nitrogen atom (Cu-N, 2.031 ?) of the Bcegly? ligand and the nitrogen atom of the Im ligand (Cu-N, 1.970 ?) and the axial positions are occupied by oxygen atoms of the Bceglyligand (Cu-O, 2.357 ?) and the perchlorate ion (Cu-O, 2.830 ?). The Bcegly? ligand fulfils the tetradentate chelate function closing three metallocycles, namely, two six-membered CuNC3O cycles and one five-membered CuNC2O cycle. Complex cations, ClO 4 ? anions, and crystallization water molecules are connected by an extended system of hydrogen bonds.  相似文献   

7.
Zinc(II) complexes with 1,10-phenanthroline (phen) and 2,2′-bipyridine (bpy) containing two different anions have been synthesized and characterized by elemental analysis, IR-, 1H?NMR-, 13C?NMR spectroscopy. The single crystal X-ray data of [Zn(phen)2(CCl3COO)(H2O)](NO3) show the complex to be monomeric and the Zn atom with an unsymmetrical six-coordinate geometry, coordinated by four nitrogen atoms of “phen”, one trichloroacetate and one water. The crystal structure of [Zn(bpy)2(CH3COO)](ClO4)?·?H2O shows each zinc atom chelated by the nitrogen atoms of “bpy” and also two oxygen atoms of acetate. From the infrared spectra and X-ray crystallography, it is established that coordination of the carboxylate group to zinc is different for trichloroacetate and acetate.  相似文献   

8.
1 INTRODUCTION Nickel is vital for organism as a trace element and it often acts as component or secondary factor of enzyme. In the latest two decades, biological inor- ganic chemistry of nickel has become one of the hottest fields and the coordination chemistry of nic- kel has made a great progress[1]. Complexes built upon organic aromatic carboxylic acid and metallic ion have attracted chemists’ interest for years due to their potential applications in material, medicine, molecular ele…  相似文献   

9.
《Polyhedron》1987,6(7):1533-1539
Perchlorate and hexafluorophosphate salts of monomeric [Cu(terpy)(OOCH)(OH2)]+ and dimeric [Cu(terpy)(OOCR)]22+ cations (terpy = 2,2′:6′,2″-terpyridine, R = CH3 or C2H5) have been synthesized and characterized by IR, electronic and ESR spectra, and analytical data. Spectroscopic results indicate a five-coordinate, close-to-square pyramidal geometry around the copper(II) ion. The half-field absorption in the ΔMs = 2 region of powdered X-band ESR spectra has been observed for the dimeric species. The crystal structure of [Cu(terpy)(OOCH)(OH2)](ClO4) has been determined by X-ray diffraction methods. The compound crystallizes in the space group P21/c with unit-cell dimensions: a = 7.341(3), b = 13.919(2), c = 18.081(3) Å, β = 101.68(3)°, V = 1809(1) Å3, Z = 4. The structure was refined to R = 0.044, Rw = 0.051.  相似文献   

10.
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   

11.
Two new Pb(II) complexes, [Pb(TPT)(NO3)2] n (1) and [Pb(TPT)2(ClO4)(H2O)] · ClO4 · H2O (2) (TPT is the abbreviation of 3,5,6-tris(2-pyridyl)-1,2,4-triazine), have been synthesized and characterized by single-crystal X-ray diffraction. Lead(II) in the compounds of 1 and 2 is nine coordinate (rare mode), PbN3O6 and PbN6O3, respectively. Both have hemidirected coordination geometries. The supramolecular features in these complexes are guided/controlled by hydrogen bonding and weak directional intermolecular C–H ··· O and π ··· π interactions. The thermal stabilities of 1 and 2 were investigated by thermogravimetric measurements.  相似文献   

12.
In a 1D network of (1)(∞){[Fe(CH(3)CN)(4)(pyrazine)](ClO(4))(2)}, the presence of four neutral nitrile molecules besides the pyrazine donors in the first coordination sphere of iron(II) allows one to achieve a ligand field strength appropriate for the "spin-crossover" occurrence.  相似文献   

13.
Crystals of [Cu(DAF)(H2O)]BF4(I) and [Cu(DAF)(ClO4)] (II) (DAF is diallyl formamide) were synthesized by an alternate-current electrochemical method, and their structures were determined (MoK radiation, 1247 and 859 independent reflections with I 2(I), R= 0.043 and 0.032 for Iand II, respectively). The complexes crystallize in space group P21/n, Z= 4. For I, a= 10.782(3) Å, b= 12.096(5) Å, c= 9.185(3) Å, = 103.62(3)°, and V= 1164.2(7) Å3; for II, a= 10.064(3) Å, b= 10.753(6) Å, c= 10.002(3) Å, = 87.52(4)°, and V= 1081.4(8) Å3. The copper atom in structures Iand IIcoordinates both C=C bonds in one DAF molecule and oxygen atom of the amide group of another DAF molecule, as well as an oxygen atom of H2O (in I) or ClO4(in II) in the axial position. The uncommon behavior of the anions in structures Iand IIis explained by their different values of Pierson hardness.  相似文献   

14.
The title complex, C37H34N6NiO5, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21/c with a = 1.15244(8), b = 1.69679(12), c = 1.78341(13) nm, β = 102.2320(10)°, V = 3.4082(4) nm3, Z = 4, Mr = 701.41, F(000) = 1464, Dc = 1.367 g/cm3 and μ(MoKα) = 0.622 mm-1. The structure was refined to R = 0.0459 and wR = 0.1199 for 5718 observed reflections. The intramolecular hydrogen bonds in the crystal structure play important roles in the title complex's thermostability.  相似文献   

15.
1 INTRODUCTION The studies of organotin compounds are of current interest owing to their wide range of applications such as biocides and thermal stabilizers for PVC plastic etc. Besides, the pharmaceutical properties such as the antitumor activities of organotin carboxylates have been investigated[1, 2]. In recent years, reports of synthesis and structural elucidation of various organotin carboxylic esters have appeared, revealing various new structural possibilities[3]. Since Kealy an…  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.
以三(2-吡啶甲基)胺(tpa)为螯合配体合成了2种新型的钌配合物[Ru(tpa)(H_2biim)]·(ClO_4)_2(1)和[Ru(tpa)(H_2bbim)]·(ClO_4)_2(2)(H_2biim=2,2′-联咪唑;H2bbim=2,2′-苯并联咪唑),并研究了它们的晶体结构和紫外光谱.通过理论计算对紫外光谱峰值进行了指认,光谱模拟和实验吻合.计算发现2种配合物分子的最低空轨道落在H_2biim或H_2bbim配体上,和其他Ru-H_2biim(H_2bbim)配合物有所不同.  相似文献   

18.
Two new transition metal complexes, [Ni(bipy)2Cl]·ClO4 (bipy = 2,2'-bipyridine) 1 and [Zn(bipy)2Cl]·BF4 2, have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 crystallize in monoclinic space group P21/n with Z = 4. For 1, a = 10.776(1), b = 12.067(1), c = 16.146(2)(A), β= 93.021(2)o, V = 2031.9(4)(A)3, Mr = 505.98, Dc = 1.654 g/cm3, μ = 1.255 mm-1, F(000) = 1032, the final R = 0.0406 and wR = 0.1002 for 3983 observed reflections with Ⅰ > 2σ(I). For 2, a = 10.758(4), b = 12.058(4), c = 16.135(5) (A), β = 104.57(1)o, V = 2025.7(12) (A)3, Mr = 500.00, Dc = 1.639 g/cm3, μ = 1.396 mm-1, F(000) = 1008, the final R = 0.0470 and wR = 0.1237 for 3759 observed reflections with Ⅰ > 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. A one-dimen- sional zigzag double hydrogen-bonding-chain is generated by the intermolecular M-bipy …anion…bipy--M hydrogen bonding interactions between the chelating ligands of bipy and anion.  相似文献   

19.
Thin films of the adduct formed from the electrostatic association of the metallopolymer, [Ru(bpy)(2)(PVP)(10)](2+), and the Dawson polyoxomolybdate α-[Mo(18)O(54)(SO(4))(2)](4-), POMo, have been formed on ITO electrodes using an alternate immersion approach. The Ru/POMo ratio is 4.5:1, which exceeds the 2:1 ratio expected on the basis of the charges of the Ru(2+) and POMo(4-) building blocks. This behavior arises because of the polymeric character of the cation. In the presence of a substrate that has an abstractable proton such as benzyl alcohol, these ruthenium-sensitized polyoxomolybdate films generate significant photocurrents under visible irradiation. Significantly, increasing the surface coverage of the adduct from 1.4 × 10(-10) to 8.1 × 10(-10) mol cm(-2) does not measurably increase the photocurrent observed. Scan-rate-dependent cyclic voltammetry reveals that the rate of homogeneous charge transport through the film is slow, which most likely results in only a fraction of the film thickness being active for photoelectrocatalysis. The photocurrent increases markedly when the driving force for the oxidation of POMo(5-), created by the photoelectrocatalytic oxidation of benzyl alcohol, is increased. This result is consistent with the dynamics of heterogeneous electron transfer being centrally important to the regeneration of the photoelectrocatalyst. A system in which the surface coverage and applied overpotential are optimized produces a photocurrent density of 190 ± 18 nA cm(-2) under 480 ± 5 nm irradiation.  相似文献   

20.
In this article, two chiral ruthenium(II) complexes, Λ/Δ-[Ru(bpy)2(H2iip)](ClO4)2 (Λ-1 and Δ-1, bpy = 2,2-bipyridine; H2iip = 2-(indol-3-yl)-imidazo[4,5f][1, 10 G.L. Duveneck, C.V. Kumar, N.J. Turro, J.K. Barton. J. Phys. Chem., 92, 2028 (1988).10.1021/j100318a064 S.K. Singh, S. Joshi, A.R. Singh, J.K. Saxena, D.S. Pandey. Inorg. Chem., 46, 10869 (2007).10.1021/ic700885m ]phenanthroline), were synthesized and investigated as c-myc G4 DNA stabilizers. The interaction of both complexes with c-myc G4 DNA has been studied using UV–vis spectra, CD spectra, and ITC experiments, and the results show that both isomers strongly bind with c-myc G4 DNA. Furthermore, the FRET melting point experiments give a ΔTm for Λ-1 and Δ-1, which is about 9.5 and 8.3 °C, respectively, indicating that both isomers can stabilize the G-quadruplex conformation of c-myc oncogene in vitro. As a result, the replication ability of c-myc DNA, as evaluated by using PCR-stop assay, by both isomers. Besides, the inhibitory activity evaluated by MTT assay showed that Λ-1 and Δ-1 can inhibit the growth of MDA-MB-231 cells, suggesting their potential utility as inhibitors targeting to c-myc G-quadruplexe in chemotherapy.  相似文献   

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