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1.
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   

2.
《Polyhedron》2002,21(12-13):1279-1288
The crystal structures of two mono(dpyam)copper(II) complexes, [Cu(dpyam)(NO2)2] (1) and [Cu(dpyam)(H2O)2(SO4)] (2) and two dithiocyanate compounds containing bis(dpyam)copper(II) units, [Cu(dpyam)2(NCS)](SCN)·0.5DMSO (3) and [Cu(dpyam)2(SCN)2] (4) have been determined by X-ray crystallography. The second orthorhombic form of the monomeric Cu(II) complex 1 was obtained by the reaction of di-2-pyridylamine (dpyam) with CuCl and NaNO2 in water–methanol solution. Each copper(II) ion in 1 exhibits a tetrahedrally-distorted square base of the CuN2O2 chromophore, with off-the-z-axis coordinated nitrito groups weakly bound in approximately axial positions. Complex 2 is an example of a polymeric copper(II) derivative containing the bidentate bridging sulfate ligand in the long-bonded axial positions. Each copper(II) ion in 2 shows an elongated tetragonal octahedral stereochemistry. The CuN4N′ chromophore of 3 involves a square-based pyramidal structure, slightly distorted towards a trigonal bipyramidal stereochemistry, τ=0.13. One of the SCN anions is bonded to the copper(II) ion via the N atom in the axial position of the square pyramid. Complex 4 is centrosymmetric and octahedrally elongated, with the SCN anions coordinating in axial positions via the S atom. The structures of complexes 14 and their ESR and electronic reflectance spectra are compared with those of related complexes.  相似文献   

3.
4.
5.
The synthesis of the [Cu(H2L)](NO3)2 complex (I) and of a mixed-valent complex [Cu(H2L)Cl]2[CuCl2]Cl·0.5H2O (II), where L is chiral bis(menthane) propylenediaminodioxime. According to the data of single-crystal X-ray diffraction analysis, compounds I and II have ionic structures. In complex cations, the Cu2+ ion coordinates four N atoms of tetradentate chelate ligand, namely, the H2L molecule. The coordination surrounding of the Cu atom in I is a distorted square CuN4, while in II, it is a distorted square pyramid CuN4Cl. The complex anion [CuCl2]? in II has linear structure. The mutual arrangement of oxime groups in H2L corresponds to amphi-configuration of a ligand and therefore, intramolecular hydrogen bond O...H-O are formed in H2L. The complex cations in compound II are joined in dimers through hydrogen bonds Cl...H-O. The values μeff for I and II are equal to 1.82 and 2.82 μB, respectively.  相似文献   

6.
[[UO2(L)(OH)] (I), (CN3H6)2[(UO2)2CrO4(L)4] · 2H2O (II), and [UO2(H2O)5][(UO2)2Cr2O7(L)4] (III) crystals, where L is picolinate ion C5H4NCOO?, have been synthesized and studied by X-ray diffraction and IR spectroscopy. Complex I crystallizes in triclinic system with the unit cell parameters a = 6.2858(5) Å, b = 7.9522(5) Å, c = 8.3598(6) Å, α = 79.527(6)°, β = 87.760(6)°, γ = 79.126(6)°, space group P $\bar 1$ , Z = 2, R = 0.0306, and complexes II and III crystalize in monoclinic system with a = 8.8630(9) Å, b = 13.4540(13) Å, c = 31.266(3) Å, β = 93.118(3)°, space group C2/c, Z = 4, R = 0.0187 (II), and a = 7.3172(4) Å, b = 15.4719(8) Å, c = 16.6534(10) Å, β = 98.943(4)°, space group P21/m, Z = 2, R = 0.0588 (III). The structure of complex I is built of electronegative [UO2(L)(OH)] chains, which belong to the AT11M2 crystallochemical group (A = UO 2 2+ , T11 = L, M2 = OH?) of uranyl complexes. The structure of complexes II and III contains [(UO2)2(L′)(L)4]2? dimers (L′ = CrO 4 2? or Cr2O 7 2? ), which belong to the A2B2B 4 01 group (A = UO 2 2+ ,B2 = L′, B01 = L). The specifics of intermolecular interactions in the structures of complexes I–III and some their analogues have been considered using molecular Voronoi-Dirichlet polyhedra.  相似文献   

7.
The complexes [MI2(CO)3(NCMe)2] (M = Mo or W) react with one equivalent of L in CH2Cl2 at room temperature to give initially the mononuclear seven-coordinate complexes [MI2(CO)3(NCMe)L] which have been isolated for M = W; L = 3Cl-py, 3Br-py, 4Cl-py and 4Br-py. These compounds dimerise to give the iodidebridged dimers [M(μ-I)I(CO)3L]2 by displacement of acetonitrile. When M = Mo; L = 3Cl-py, 3Br-py, 4Cl-py and 4Br-py, and when M = Mo and W; L = py, 2Me-py (for M = W only), 4Me-py, 3,5-Me2-py, 2Cl-py and 2Br-py, only the dimeric complexes have been isolated. The ease of dimerisation of [MI2(CO)3(NCMe)L] is discussed in terms of the steric and electronic effects of the substituted pyridines.  相似文献   

8.
《Polyhedron》1999,18(5):729-733
Equimolar quantities of [Mo (CO) (η2-RC2R′)2Cp] [BF4] (R=R′=Me Ph R=Me R′=Ph) and L L′ or L″ {L L′ or L″= [WI2 (CO){PhP(CH2CH2PPh2)2-PP′} (η2-RC2R′)]} (L R=R′=Me L′ R=R′=Ph L″ R=Me R′=Ph) react in CH2Cl2 at room temperature to give the new bimetallic complexes[Mo (CO) (L L′ or L″–P) (η2-RC2R′)Cp] [BF4] (1–9) via displacement of the alkyne ligand on the molybdenum centre The complexes have been characterised by elemental analysis IR and 1 H NMR spectroscopy and in selected cases by 31 P NMR spectroscopy.  相似文献   

9.
应用密度泛函理论BP86方法结合自然键轨道分析方法对具有分子导线潜在应用前景的金属串配合物[Ni3(L)4(NCS)2](L = dpa- (1), mpta- (2), mdpa- (3), mppa- (4))进行研究,分析了桥联配体L对Ni―Ni相互作用和磁耦合性质的影响.结果得到: (1)配合物的基态均是对应于五重态(HS)的反铁磁(AF)单重态, HS的能量和结构与AF态相近, Ni36+链形成了三中心四电子σ键(σ2σnb1σ*1). (2) dpa-引入甲基成为mdpa-,对Ni―Ni、Ni―N距离影响不大; 3H-吡咯环和噻唑环取代吡啶环后, N1―N2、Ni―Ni距离增大, Ni2―N2键长缩短,但噻唑环的影响较小;故Ni―Ni相互作用强度为1 ≈ 3 > 2 > 4. (3)预测了3和4的Jab值为-103和-88 cm-1,随Ni―Ni相互作用增强磁耦合效应增大. Ni―Ni相互作用越大,通过Ni36+链σ型轨道的直接磁耦合越强; Ni2―N2键越强,通过涉及桥联配体的间接磁耦合越强,直接磁耦合比间接磁耦合更强.  相似文献   

10.
采用密度泛函的B3LYP和UB3LYP方法分别优化了一系列[Ru(iph)(L)2]2+ (L=cpy (1), mpy (2), npy (3); 其中iph为2,9-双(1′-甲基-2′-咪唑)-1,10-邻二氮杂菲, cpy为4-氰基嘧啶, mpy为4-甲基嘧啶, npy为4-氮二甲基嘧啶)配合物的基态和激发态结构. 利用含时密度泛函理论(TD-DFT)方法, 结合极化连续介质(PCM)模型计算了它们在丙酮溶液中的吸收和发射光谱. 研究结果表明: 优化得到的几何结构参数和相应的实验值符合得非常好. 1和2的最高占据分子轨道主要由金属的d轨道和iph配体的π轨道构成, 但是3主要占据在npy配体上, 而它们的最低空轨道主要由iph配体的π反键轨道占据. 因此, 1和2的最低能吸收和发射属于金属到配体(MLCT)和配体内部(ILCT)的电荷转移跃迁, 而3属于两个配体之间的电荷转移(LLCT)跃迁. 三个配合物的最低能吸收分别在509 nm (1), 527 nm (2)和563 nm (3), 其磷光发射分别在683 nm (1), 852 nm (2)和757 nm (3). 这显示出通过调节L配体的π电子给予能力可以改变最低能吸收和发射的跃迁性质和发光颜色.  相似文献   

11.
Abstract

Two new ruthenium(II) complexes, [Ru(bpy)2(DClPIP)](ClO4)2 (1) and [Ru(phen)2(DClPIP)](ClO4)2 (2) (bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, and DClPIP = 2-(2,4-dichlorophenyl)-1H-imidazo[4,5-f][1, 10]phenanthroline), have been prepared in high yield by using microwave-assisted synthesis technology. The anticancer activity of the two ruthenium(II) complexes against A549, C6, CNE-1 and MDA-MB-231 cell lines has been evaluated by MTT assay and results showed that 2 exhibited higher antitumor activity than 1 toward all the selected tumor cell lines. Besides, A549 cell line was sensitive to both ruthenium(II) complexes, especially to 2 (IC50 = 8.01?±?0.36?μM). Meanwhile, 2 showed low toxicity against MCF-10A human normal cells. Furthermore, the DNA-binding properties of the two new ruthenium(II) complexes with CT-DNA have been investigated by electronic absorption titration, luminescence spectra, circular dichroism spectra and viscosity measurements. The results suggested that 1 and 2 were able to interact with CT-DNA via intercalative mode with a strong binding affinity in the order 2?>?1. All of these results suggested that anticancer activity of both ruthenium(II) complexes could be closely related to their interaction with DNA.  相似文献   

12.
Electrochemical studies of the newly synthesized bis(triphenyl phosphine) ruthenium(II) complex, cis-[RuCl2(L)(PPh3)2] (1, with L = 2-(2′-pyridyl)quinoxaline, C13N3H9), were performed in acetonitrile (ACN). For this purpose, cyclic voltammograms (CVs) as well as electrochemical impedance spectra (EIS) were recorded on either glassy carbon (GC), platinum (Pt), gold (Au), or multi-walled carbon nanotube (MWCNT) electrodes. Qualitative examination of solutions of 1 in ACN was performed on the basis of conductivity measurements and electrospray ionization mass spectrometry (ESI–MS). The conductivity data suggest that 1 is a 1 : 1 type electrolyte in ACN. The ESI spectra further demonstrate that upon dissolution of 1 in ACN progressive replacement of chloro- and PPh3-ligands by ACN occurs, leading to formation of [RuCl(L)(PPh3)(CH3CN)2]+Cl?, [2 + Cl ? ]. The CVs recorded for [2 + Cl ? ] on various working electrodes demonstrate that the reversibility of the redox couple 22 +/+ enhances with the order: Au < Pt < MWCNT < GC. The EI spectra verify that GC and MWCNT electrodes provide insignificant barrier for interfacial electron transfer since they afford less charge-transfer resistance.  相似文献   

13.
《Polyhedron》2001,20(15-16):2073-2082
Reactions of nickel(II) salts with substituted ethane-1,2-diamine where one of the amine nitrogens is a part of a flexible cyclic ring, e.g. 1-(2-aminoethyl)piperidine (L), 1-(2-aminoethyl)pyrrolidine (L′) and 4-(2-aminoethyl)morpholine (L″) produce a number of complexes of the type: (i) Ni(AA)2X2 (where X=CF3CO2 , SCN and NO2 ; AA represents L/L′/L″); (ii) Ni(AA)2(CH3CN)2X2 (X=ClO4  and NO3 ); (iii) Ni(AA)2(H2O)2X2 (X=CF3SO3 , Cl, Br and I); and (iv) Ni(AA)2(H2O)4X2 (X=0.5SO4 2−, 0.5SeO4 2− and CF3SO3 ). The complexes possess octahedral geometry. The major complexes upon desolvation retain trans-geometry, some of which are cis with respect to the counter-anion and a few of them are square planar. X-ray single crystal structure analyses of trans-[NiL2(CH3CN)2](ClO4)2, trans-[NiL2(NCS)2] (violet) and trans-[NiL″2(NCS)2] (sky-blue) have been done. The violet and sky-blue thiocyanato species have blue and green coloured isomers, respectively, and these pairs of isomers are proposed to be conformational isomers. Solid state thermal investigation of the complexes has been carried out. The complexes show thermochromism due to deaquation–anation/deaquation reaction/change of conformation. Only [NiL2](ClO4)2, [NiL′2(CF3CO2)2] and [NiL″2(NO2)2] undergo thermally induced phase transition. The effect of flexible ring size on diamine has been discussed.  相似文献   

14.
A new compound [Ni(L)(H2O)2][Ni2(L)(NTA)2]6H2O (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]- docosane, NTA = nitrillotriacetate) was prepared and its structure was determined by the X-ray diffraction method. Complex 1 crystallizes in the monoclinic space group P21/c with a = 11.217(2) , b = 18.048(5) , c = 15.393(3) , = 90.78(2)°, V = 3115.9(12) 3, and Z= 2, Each nickel atom in complex 1 has a distorted octahedral coordination geometry with an inversion center. Magnetic susceptibility measurement showed a weak intramolecular antiferromagnetic interaction between two Ni(1) and Ni(2) centers with a J value of -0.93(1) cm–1. The intermolecular hydrogen-bonding interaction gives rise to a two-dimensional network.  相似文献   

15.
16.
The Eschweiler-Clarke reaction of ethylenediamine with formaldehyde and formic acid yielded N,N,N′,N′-tetramethylethylenediamine, which was alkylated with allyl chloride or allyl bromide to give the corresponding N,N′-diallyl-N,N,N′,N′-tetramethylethylenediaminium (L2+) dihalides. In methanolic solutions of copper(II) halide and an appropriate ligand, ac electrochemical synthesis with copper wire electrodes afforded single crystals of Cu(I) complexes with L2+: [L0.5CuCl2] (I), [L0.5CuCl0.72Br1.28] (II), and [L0.5CuBr2] (III). The crystal structures of complexes I–III were determined by X-ray diffraction study. The isostructural crystals of I and II are monoclinic, space group P21/n, Z = 4. For I: a = 7.632(4) Å, b = 11.318(5) Å, c = 10.635(5) Å, β = 98.551(7)°, V = 908.4(7) Å3. For II: a = 7.7415(7) Å, b = 11.4652(9) Å, c = 10.7267(10) Å, β = 98.351(4)°, V = 942.0(2) Å3. The organic cation L2+ acts as a bridge linking a pair of separate cuprous halide fragments Cu2X4. Although being isostoichiometric with I and II, complex III has a different structure. The crystals of III are monoclinic, space group P21/c, a = 6.519(2) Å, b = 9.060(3) Å, c = 16.284(6) Å, β = 97.219(4)°, V = 954.2(6) Å3, Z = 4. In structure III, the inorganic fragment forms infinite polymer chains (CuBr 2 ? ) n . The organic and inorganic parts are held together only by electrostatic interactions. Structures I–III are stabilized by hydrogen bonds (C)H…X (2.6–2.9 Å).  相似文献   

17.
本文研究了配合物[Cp_2Ti(L)X](Cp:C_5H_5,Me~-C_5H_4,C_5Me_5;L:瞵、异腈、吡啶、胺、一氧化碳等;X:F,Cl,Br,I)的ESR谱,获得了这些配合物的波谱参数。发现在Cl,Br,I三个系列中,g值与钛超精细偶合常数a(Ti)值随L的变化呈线性关系。观测到大量g>g_e的Ti(Ⅲ)配合物的ESR谱,对其规律性进行了探讨。  相似文献   

18.

A new dinuclear Cd(II) complex, [L2Cd2(μ-N3)2(N3)2], containing two end-on bridging azide ligands, two monodentate N3 ligands and 1,4,7-triazacyclononane as the capping ligand, has been synthesized and its structure determined by X-ray crystallography. The complex crystallizes in the monoclinic space group P21/c with a=8.467(3), b=14.359(5), c=10.115(4)Å, β=95.026(6)° and z=4. The cadmium(II) centre is six-coordinate with distorted octahedral geometry, bonded to three N atoms of the 1,4,7-triazacyclononane, two nitrogen atoms of μ-azide bridges and one nitrogen atom of a monodentate azide ligand. Neighboring Cd(II) atoms are linked by the double end-on azide bridges.  相似文献   

19.
Synthetic routes to the cationic complexes [η5-C9H7Fe(CO)[2L]+, (L = CO, phosphine, phosphite, nitrile, pyridine) have been investigated. The most versatile method is oxidation of the dimer [η5-C9h7Fe(CO)2]2 with ferricinium ion. in the presence of the appropriate ligand. [η5-C9H7Fe(CO)3]+ is best prepared by oxidation of the dimer with Ph3CBF4. This tricarbonyl cation readily loses one CO group on reactiom with phosphines and P(OCH3). The acentonitrile ligand [η5-C9H7Fe(CO)2CH3CN]+ can also be replaced bny phosphines. Finally, reactions of η5-C9H7Fe(CO)2X, (X = Br, I) with phosphines also yield cationic products isolatedas PF6 salts.  相似文献   

20.
The ability of cis-[Pt(NH(3))(2)(L)](2+/+), a molecular fragment of the anticancer drug cisplatin, to bind to purines and CO by pi-back-donation from Pt to the ligand was examined computationally. Optimized geometries and computed vibrational frequencies suggest that cis-[Pt(NH(3))(2)(L)](2+/+) (L = Cl, H(2)O, NH(3)) is a poor pi-donor and that pi-back-donation does not play an important role for Pt(II)-ligand interactions in general.  相似文献   

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