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Theoretical studies on the complexes Ru(bpy)2L2+, Ru(phen)2L2+ (L=pytp,pztp) were carried out by using the density functional theory (DFT) method at B3LYP/LanL2DZ level. The relation between electronic structures and anti-cancer activities of complexes was investigated. The increasing of N in the main ligand can strengthen the interaction of complexes with DNA and anti cancer activities of complexes. The calculation results show that for complexes I-IV, their energies of LUMO orbital are in the order of εI>εII, εIII>εIV, the electron cloud components of LUMO come mainly from main ligands and the content distributing is in the order of I相似文献   

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1 INTRODUCTION The synthesis of new organic-inorganic hybrid compounds is a relatively new research area that has developed rapidly in the last several years[1]. Bische- late ligand[2, 3], such as azobis(2-pyridine), is a novel tetradentate ligand expect…  相似文献   

5.
The electronic structures of chromium and vanadium centers coordinated by three reduced 1,2-diketones have been elucidated by using density functional theory (DFT) calculations and a host of physical methods: X-ray crystallography; cyclic voltammetry; ultraviolet-visible (UV-vis), nuclear magnetic resonance (NMR), and electron paramagnetic resonance (EPR) spectroscopy; and magnetic susceptibility measurements. The metal center in octahedral [CrIII(L*)3]0 (1), a CrIII (d3) ion is coupled antiferromagnetically to three monoanionic ligand pi-radicals affording an S ) 0 ground state. In contrast, Na2(Et2O)2[VIV(LRed)3] (2) (S ) 1/2), possesses a central VIV (d1) ion O,OE-coordinated to three closed-shell, doubly reduced ligands which in turn are coordinated by two Na cations enforcing a trigonal prismatic geometry at the vanadium center. 2 can be oxidized electrochemically by one and two electrons generating a monoanion, [V(L)3]1-, and a neutral species, [V(L)3]0, respectively. DFT calculations atthe B3LYP level show that the one-electron oxidized product contains an octahedral VIV ion coupled antiferromagnetically to one monoanionic ligand pi-radical [VIV(L*)(LRed)2]1- (S ) 0). In contrast, the two-electron oxidized product contains a VIII ion coupled antiferromagnetically to three ligand pi-radicals in an octahedral field[VIII(L*)3]0 (S ) 1/2).  相似文献   

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Based on the complex ligand CuL (H2L = 2,3-dioxo-5,6:14,15-dibenzo-7,13-diphenyl-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene), two novel oxamido-bridged trinuclear complexes have been prepared. They are of the formula Cu(CuL)2(ClO4)2 · 4C2H5OH (1) and [(CuL)2Zn(C2H5OH)2](ClO4)2 · 2C2H5OH (2). The crystal structures of the two complexes have been determined by X-ray crystallography. In complex (1), the central Cu is in a complete square-planar environment, bonding to four oxygen atoms of the oxamido macrocyclic ligand, while in complex (2), the Zn center is six-coordinate in an octahedral geometry, the four oxygen donors from macrocyclic ligand form the basal plane and the axial positions are occupied by other oxygen atoms from C2H5OH molecules. The spectroscopic properties have been investigated and the EPR spectra have been simulated by WINEPR and SimFonia programs.  相似文献   

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The novel complex [Cu(men)2][Cu2Cd2Cl2(CN)6] (I) was isolated from the aqueous-ethanol system containing CuCl2, men (men = N-methylethane-1,2-diamine) and K2[Cd(CN)4] in the presence of dilute hydrochloric acid and chemically and spectroscopically characterised. The crystal structure of I consists of [Cu 2 I (CN)6] and [Cd2Cl2(CN)6] building units bridged by cyanide ligands and forms a three-dimensional skeleton with cavities. [Cu(men)2]2+ cations in which two men ligands are chelated (mean Cu-N is 2.033(6) Å) are located in the cavities. The coordination polyhedron around the Cu(II) atoms is formed as a tetragonal bipyramidal by two weaker axial Cu-Cl bonds (2.8642(12) Å) with chlorido ligands from the skeleton. The Cu(I) and Cd(II) atoms in the skeleton exhibit tetra-(CuC4 chromophore) and penta-coordination (CdN3Cl2), respectively. The temperature-dependent susceptibility measurements indicate a Curie-Weiss-like behaviour and the presence of weak anti-ferromagnetic interaction.  相似文献   

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The hydrothermal reaction of K(3)[Fe(CN)(6)], CuCl(2), and 2,2'-bipyridine (bipy) resulted in the formation of a 2D cyanide-bridged heterobimetallic Fe(II)-Cu(I) complex, [Fe(bipy)(2)(CN)(4)Cu(2)], 1. Working in the same conditions, but using 2,2'-bipyrimidine (bpym) instead of bipy and methanol as solvent, we obtained the homometallic Cu(I) complex [Cu(2)(CN)(2)(bpym)](2), 2. The structure of 1 consists of cyanide-bridged Fe(II)-Cu(I) layers, constructed from alternately fused 6 (Fe(2)Cu(4)) and 10 (Fe(2)Cu(8)) metal-membered centrosymmetric rings, in which copper(I) and iron(II) ions exhibit distorted trigonal planar and octahedral cooordination environments, respectively. The formation of 1 can be explained by assuming that, under high pressure and temperature, iron(III) and copper(II) ions are reduced with the simultaneous and/or subsequent substitution of four cyanide ligands by two bipy molecules in the ferricyanide anions. It is interesting to note that 1 is the first cyanide-bridged heterobimetallic complex prepared by solvothermal methods. The structure of 2 consists of neutral 2D honeycomb layers constructed from fused Cu(6)(CN)(4)(bpym)(2) rings, in which copper(I) atoms exhibit distorted tetrahedral geometry. The isolation of 1 and 2, by using K(3)[Fe(CN)(6)] as starting material, demonstrates that hydrothermal chemistry can be used not only to prepare homometallic materials but also to prepare cyanide-bridged bimetallic materials. The temperature dependence of chi(M)T and M?ssbauer measurements for 1 reveal the existence of a high spin <--> low spin equilibrium involving the Fe(II) ions.  相似文献   

10.
[Cu(L)(n)](2+) complexes of 1,2-dihexanoyl-sn-glycero-3-phosphocholine (L = D6PC) are formed upon electrospray ionization mass spectrometry (ESI-MS) of an 8 mM solution of D6PC with 4 mM CuCl(2) in 10 mM ammonium acetate buffer, pH 6.1. The collision-induced dissociation (CID) reactions of the [Cu(L)(n)](2+) complexes were examined in a linear ion trap mass spectrometer. A rich fragmentation chemistry was observed, including: loss of a neutral ligand; intermolecular ligand-ligand S(N)2 methylation; metal ion induced ligand fragmentation via carboxylate abstraction; and phosphate abstraction. The dominant reaction channel depends on the size (n) of the complex. Thus loss of neutral ligand(s) is the sole reaction channel for n = 5-7. At n = 4, S(N)2 methylation and carboxylate abstraction start to compete with neutral ligand loss. At n = 2 the carboxylate abstraction and phosphate abstraction reactions dominate the CID spectrum. The carboxylate abstraction and phosphate abstraction reactions are likely to be driven via neighboring group pathways. PM3 calculations, carried out to compare competing neighboring pathways based on the relative stabilities of the product ions, suggest a preference for five-membered ring formation for ligand fragmentation involving both carboxylate and phosphate abstraction.  相似文献   

11.
New nickel, cobalt and copper complexes with benzene-1,2-dithiole (bdt), of general formula R[M(bdt)2]: M = Ni, Co and Cu; R = Me4N, Et4N, Pr4N, Me3PhN, MePh3P, Ph4P have been synthesized and characterized by standard physico-chemical methods (elemental analyses, magnetochemical and conductivity measurements, i.r. and u.v.–;vis. spectroscopy). X-ray structural analysis of (MePh3P)[M(bdt)2], M = Ni, Co and Cu, confirms that the MS4 chromophore lies in a slightly distorted square coordination arrangement around the central atom. The three complexes have also been studied by cyclic voltammetry.  相似文献   

12.
Both [Cu(DAT)2(PA)2] (1) and [Cu(DAT)2(HTNR)2] (2) were prepared from 1,5-diaminotetrazole (DAT) and copper trinitrophenol, 1 for picrate (PA) and 2 for styphnate acid (2,4,6-trinitro resorcinol, TNR), and were characterized by elemental analysis, FT-IR spectroscopy, and single crystal X-ray diffraction. The space group of these compounds is P21/c (monoclinic). The lattice parameters are similar [a = 11.405(3) Å, b = 14.867(3) Å, c = 8.099(2) Å for 1 and a = 12.262(3) Å, b = 14.900(3) Å, c = 7.243(2) Å for 2], except the β = 106.257(3)° in 1 and β = 92.989(4)° in 2. Both have extended structures due to hydrogen bonds, but there are some differences because of the ligands induced effect. Differential scanning calorimetry analysis shows that two exothermic processes take place in both complexes, the first peak temperatures are 488.2 K for 1 and 519.2 K for 2. The kinetic parameters of the first exothermic process were studied by using Kissinger’s method and Ozawa’s method, in which the enthalpy of formation (?7346 and ?5706 kJ M?1), critical temperature of thermal explosion (475.0 and 515.8 K), entropy of activation (ΔS), enthalpy of activation (ΔH), and free energy of activation (ΔG) were calculated and obtained as ?117.25 J K?1 M?1, 140.64 kJ M?1, 196.44 kJ M?1 and ?219.1 J K?1 M?1, 383.56 kJ M?1, 495.34 kJ M?1 for 1 and 2, respectively. The sensitivity test results showed that both compounds were sensitive to impact (<5 J) and flame (>20 cm) rather than friction.  相似文献   

13.
A new Cu(I)-dicyanamide with formula [Cu2(L)(dca)2]n (dca = dicyanamide anion, L = 1,4-bis(3-furanyl)-2,3-diaza-1,3-butadiene) has been synthesized and structurally characterized.The complex crystallizes in the monoclinic system, space group P21/n with a = 9.271(2), b = 7.7355(16), c = 11.967(3) -, β = 102.693(3)°, V = 837.3(3) -3, Z = 4, Mr = 223.68, Dc = 1.775 g/cm3, μ(MoKα) = 2.567 mm-1, F(000) = 444, R = 0.0782 and wR = 0.2582 for 951 observed reflections (I > 2σ(I)).Single-crystal X-ray analysis reveals that the copper atom is three-coordinated by two nitrogen atoms from two dicyanamide anions and another one from the ligand, and each copper atom is connected by two [N(CN)2]- anions to form an infinite double-stranded bridge fashion leading to 1D ladder-like motifs.  相似文献   

14.
The crystal structures and thermal behaviour of [Cu(py)2(NCS)2] (at 293) and [Cu(4-Mepy)2(NCS)2] and 180 K) complexes have been compared with their different temperature behaviour. It was found that the thermal stability of coordinated thiocyanate ligands in the course of thermal decomposition depends not only on the properties of the ligand L, but it is related to the arrangement of the thiocyanatocopper chains in the crystal structures.  相似文献   

15.
A complete structural, calorimetric, and magnetic characterisation of the 2D coordination spin crossover polymer [Fe(pmd)(2)[Cu(CN)(2)](2)] is reported. The crystal structure has been investigated below room temperature at 180 K and 90 K, and at 30 K after irradiating the sample at low temperature with green light (lambda = 532 nm). The volume cell contraction through the thermal spin transition is only 18 A(3) which is lower than the usually observed value of around 25-30 A(3) while the average Fe-N bond distances decrease by the typical value of about 0.19 A. The structural data of the irradiated state indicate that the high spin state is well induced since the cell parameters are consistent with the data at 180 K. Calorimetric and photo-calorimetric experiments have also been performed. The entropy content for the thermal spin transition, DeltaS = 35-37 J mol(-1) K(-1) lies in the lowest range of the typical values and correlates with the low volume cell contraction. The combination of the crystallographic and calorimetric data predicts, in accordance with a mean-field approach, a linear pressure dependence of the critical temperature with a slope of 302 K GPa(-1). Magnetic measurements under pressure reveal an anomalous behaviour since the critical temperature and hysteresis do not change up to 0.22 GPa but an apparent linear dependence is obtained for higher pressures (up to 0.8 GPa) with a slope two times higher than the mean-field estimation.  相似文献   

16.
Summary The complexes [MI2(CO)3(NCMe)2] (M=Mo or W) react with one molar equivalent of L in CH2Cl2 at room temperature initially to afford the mononuclear sevencoordinate complexes [MI2(CO)3(NCMe)L] which have been isolated for L-PPh3, AsPh3, SbPh3, PPh2Cy or P(OPh3)3. Many of these complexes dimerise to give the iodide bridged compounds [{M(–I)I(CO)3L}2]via displacement of acetonitrile. When L=PPhCy2, PCy3, PEt3 or P(OMe)3 only the dimeric complexes have been isolated. The ease of dimerisation of the mononuclear complexes [MI2(CO)3(NCMe)L] is discussed in terms of the electronic and steric effects of the ligands, L. Low temperature13C n.m.r. spectroscopy of the mononuclear [Wl2(CO)3(NCMe)(EPh3)](E=P or As) complexes are interpreted as suggesting the likely stereochemistry of these seven-coordinate complexes.  相似文献   

17.
The structures of two cyanoaurate-based coordination polymers, M(mu-OH(2))(2)[Au(CN)(2)](2) (M=Cu, Ni), were determined by using a combination of powder and single-crystal X-ray diffraction techniques. The basic structural motif for both polymers contains rarely observed M(mu-OH(2))(2)M double aqua-bridges, which generate an infinite chain; two trans [Au(CN)(2)](-) units also dangle from each metal center. The chains form ribbons that interact three dimensionally through CNH hydrogen bonding. The magnetic properties of both compounds and of the dehydrated analogue Cu[Au(CN)(2)](2) were investigated by direct current (dc) and alternating current (ac) magnetometry; muon spin-relaxation data was also obtained to probe their magnetic properties in zero-field. In M(mu-OH(2))(2)[Au(CN)(2)](2), ferromagnetic chains of M(mu-OH(2))(2)M are present below 20 K. Interchain magnetic interactions mediated through hydrogen bonding, involving water and cyanoaurate units, yield a long-range magnetically ordered system in Cu(mu-OH(2))(2)[Au(CN)(2)](2) below 0.20 K, as indicated by precession in the muon spin polarization decay. Ni(mu-OH(2))(2)[Au(CN)(2)](2) undergoes a transition to a spin-glass state in zero-field at 3.6 K, as indicated by a combination of muon spin-relaxation and ac-susceptibility data. This transition is probably due to competing interactions that lead to spin frustration. A phase transition to a paramagnetic state is possible for Ni(mu-OH(2))(2)[Au(CN)(2)](2) upon application of an external field; the critical field was determined to be 700 Oe at 1.8 K. The dehydrated compound Cu[Au(CN)(2)](2) shows weak antiferromagnetic interactions at low temperatures.  相似文献   

18.
Reaction of the potassium salts of N-thiophosphorylated thioureas of common formula RC(S)NHP(S)(OiPr)(2) [R = morpholin-N-yl (HL(a)), piperidin-N-yl (HL(b)), NH(2) (HL(c)), PhCH(2)NH (HL(d))] with Cu(PPh(3))(3)I in aqueous EtOH/CH(2)Cl(2) leads to mononuclear [Cu(PPh(3))(2)L-S,S'] complexes. Using copper(i) iodide instead of Cu(PPh(3))(3)I, polynuclear complexes [Cu(n)(L-S,S')(n)] were obtained. The structures of these compounds were investigated by ES-MS, elemental analyses, 1H and 31P NMR in solution, IR and 31P solid-state MAS NMR spectroscopy. The crystal structures of [Cu(3)L(3)(a)] and [Cu(PPh(3))(2)L(b)] were determined by single-crystal X-ray diffraction.  相似文献   

19.
By single crystal X-ray diffraction the structures of [CuEn2][Pt(NO2)4] and [PdEn2][Pt(NO2)4] are determined. In the structures, the main structural moieties are identified. It is shown that the structure of [PdEn2][Pt(NO2)4] can be considered as quasi-one-dimensional: in the Y axis direction, the stacks of alternating complex cations and anions locate.  相似文献   

20.
Qi Y  Wang Y  Hu C  Cao M  Mao L  Wang E 《Inorganic chemistry》2003,42(25):8519-8523
A new family of single-stranded helices coordination polymers with mixed ligands, [M2(phen)2(e,a-cis-1,4-chdc)2(H2O)2]n (1, M=Co; 2, M=Ni; chdc=cyclohexanedicarboxylic acid; phen=1,10-phenanthroline), were prepared under hydrothermal conditions and characterized by elemental analyses, IR spectra, TG analysis, and single-crystal X-ray diffraction analysis. X-ray crystal structural analyses reveal that 1 and 2 are isomorphic and belong to the monoclinic system. C40H36Co2N4O10, P2(1)/c, a=10.0566(5) A, b=8.8843(5) A, c=20.2912(14) A, beta=100.052(3) degrees, Z=2 for 1; and C40H36Ni2N4O10, P2(1)/c, a=9.8921(6) A, b=9.0151(4) A, c=20.1628(17) A, beta=100.31(2) degrees, Z=2 for 2. In the structures of 1 and 2, the 1,4-chdc ligand possesses only one kind of e,a-cis-conformation although there are both cis- and trans-conformations in the raw material. Two oxygen atoms of one carboxyl in 1,4-chdc ligand and another oxygen atom of contraposition carboxyl link adjacent Co or Ni atoms into an infinite 1-D zigzag chain. The most attractive structural feature of 1 and 2 is that they both exhibit an infinite chiral chainlike structure with 2(1) helices along the b axis. In addition, the right-handed and the left-handed chains are alternate. Meanwhile, the adjacent chains of 1 and 2 are linked via hydrogen bonds into 2-D network structures, which further form 3-D frameworks via pi-pi interactions of 1,10-phen.  相似文献   

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