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1.
李慧  袁伟  王兴东  陈博  程延祥  谢志元  王利祥 《应用化学》2012,29(10):1148-1157
合成了7种2-苯基异喹啉及其衍生物Pt(Ⅱ)配合物。 采用1H/13C NMR、TGA、X射线单晶衍射、CV、UV-Vis和PL等测试方法对配合物的结构和性能进行了表征。 结果表明,这些Pt(Ⅱ)配合物均为平面四方配位构型。 室温下,所有配合物在二氯甲烷(DCM)溶液中均发射红光,其中配合物(CzPPiQ)Pt(acac)和(CzPPiQ)Pt(dpm)为标准的红光发射,其发射源于金属到配体的电荷转移(MLCT)(407、444和463 nm)和配体中心(LC)(353、363和376 nm)的混合激发态。 配合物在DCM溶液中的光量子产率为0.02~0.06,寿命为1.78~3.33 μs。 大位阻外围取代基的引入有效抑制了分子间相互作用。  相似文献   

2.
采用基于第一性原理的密度泛函理论对单核和双核三联吡啶Pt(II)配合物[Pt(trpy)C≡CH] (1)和[Pt(trpy)C≡ (2)的基态和激发态以及光谱性质进行了系统研究. 结果揭示了双体配合物中Pt—Pt间距离在激发态时明显短于基态时的距离, 而且双体聚合后最低能吸收和发射波长相对单体配合物发生了明显红移, 这种激发的本质被指认为是来自于[dσ*(dδ*π*)]的MMLCT (metal-to-metal-to-ligand charge transfer)电荷转移跃迁. 另外, 对研究的配合物, 用VWN (Vosko-Wilk-Nusair)泛函优化得到的几何和用SAOP(轨道势的统计平均)计算的光谱能量和实验值符合得很好, 能够准确反映实验现象.  相似文献   

3.
Reactions of 3,6-bis(2′-pyridyl)pyridazine derivatives (n-dppn) ¶For the n-dppn ligands, n stands for the size of the cyclic aliphatic ring on positions 4 and 5 of the pyridazine ring, n?=?5, 6, 8, and 12. with MX2(PhCN)2 (M?=?Pd, Pt; X?=?Cl,?Br) have been investigated. The new complexes cis-[PdCl2(n-dppn)] (n?=?5,?6,?8,?12), cis-[PtCl2(n-dppn)]?·?H2O (n?=?5,?6), cis-[PtCl2(8-dppn)] and cis-[PtBr2(5-dppn)] have been characterized by elemental analyses, conductivity measurements, infrared, electronic and 1H-NMR spectra.  相似文献   

4.
《中国化学会会志》2017,64(12):1524-1531
New complexes of nickel(II) and palladium(II) were synthesized using the ferrocenyl imine ligand, which was formed by the condensation of 2‐aminothiophenol and acetylferrocene. This bidentate Schiff base ligand was coordinated to the metal ions through the NS donor atoms. Monomeric complexes of nickel(II) and palladium(II) were synthesized by the reactions of the Schiff base ligand with nickel(II) and palladium(II) chloride in a 2:1 M ratio. In these complexes, the thiol group was deprotonated and coordinated to the metals. The molar conductivity values of the complexes in DMSO showed the presence of non‐electrolyte species. The fluorescence characteristics of the Schiff base ligand and its complexes were studied in DMSO. The synthesized complexes were characterized by FT‐IR, 1H NMR, UV–vis spectroscopy, elemental analysis, and conductometry. Furthermore, the binding interactions of the complexes with DNA were investigated by electronic absorption spectroscopy, and the intrinsic binding constant (K b) was calculated. Moreover, viscosity and melting temperature (T m) were investigated in order to further explore the nature of interactions between the complexes and DNA.  相似文献   

5.
Eight mononuclear complexes of the formula [M(N-N)(DHB)] and two binuclear complexes of the formula [M2(BPY)2(THB)] where M = Pd(II) or Pt(II), N-N = 2,2′-bipyridine (BPY), 2,2′-biquinoline (BIQ), 4,7-diphenyl-1,10-phenanthroline (DPP), 1,10-phenanthroline (PHEN); DHB = dianion of 3,4-dihydroxybenzaldehyde and THB = tetraanion of 3,3′,4,4′-tetrahydroxy benzaldazine were prepared and their electrochemical, spectral and photophysical properties were examined. These complexes were characterized by chemical analysis, IR and proton NMR spectroscopy. A detailed study on the absorption spectroscopy of these complexes was made. These complexes were found to show a low-energy solvatochromic ligand-to-ligand charge-transfer (LLCT) band. The electronic energies of these bands have been analyzed and compared with electrochemical data. Emission behaviour of the complexes of the series, [Pt(N-N)(DHB)], [Pt(N-N)(DHBA)] where DHBA is the dianion of 3,4-dihydroxybenzoic acid and [Pt2(BPY)2(THB)] was also investigated. These platinum complexes were found to emit from a low-energy state at low temperature and a high-energy state at room temperature. Photophysics of these complexes is also discussed.  相似文献   

6.
Abstract

The conformational behaviour of a series of ring substituted (ortho-Cl, F and meta or para OH) Pt(II) complexes of general formula [(1,2-hydroxyphenyl)ethylenediamine]PtL2 [L ? Cl, 1] has been studied by molecular mechanics (MM) methods. Preferred orientations of the phenyl rings, which are important for the complexes′ biological activity, were obtained by calculations of rotational energies about Csp3?Car bonds for all theoretically possible isomers and conformers, meso-λ (R,S/S,R-λ), meso-δ (R,S/S,R-δ), d,l-δ (S,S/R,R-λ) and d,l-λ (S,S/R, R-δ). The influence of the ring substituents and the conformation type on the positions of the energy minima and barriers to rotations about Csp3?Car and Car-O(H) bonds were investigated in detail. Theoretical predictions were compared with the experimental results where appropriate.  相似文献   

7.
DFT B3LYP/LANL2DZ method was employed to calculate electron properties and the second-order nonlinear optical (NLO) respond of platinum (II) complexes which have been synthesized by Weinstein group. 4,7-diphenyl-1,10-phenanthroline shows the ability to push electron in these complexes. Metal Pt plays a balancing charge role. Comparing complex 1b–6b with complex a, the βvec value of complex 1b–5b is larger than one of complex a, while the βvec value of complex 6b is smaller than one of complex a. In these seven complexes, the βvec values of complexes increase with decreasing of the energy difference between HOMO and LUMO. Moreover, the electron transfers from deeper layer occupied orbitals to empty orbitals have a distinct contribution to second-order NLO coefficient. Supported by Program for Changjiang Scholars and Innovative Research Team in University, the Foundation of Jilin Provincial Excellent Youth (Grant No. 20050107) and Youth Science Foundation of Northeast Normal University (Grant No. 111494117)  相似文献   

8.
A unique hexanuclear zinc(II) ( 1 ) and two mononuclear copper(II) ( 2 and 3 ) complexes anchored with imino phenol ligand HL 1 and HL 2 were synthesized with good yield and purity (where HL 1  = 4‐tert‐butyl‐2,6‐bis((mesitylimino)methylphenol and HL 2   =  5‐tert‐butyl‐2‐hydroxy‐3‐((mesitylimino)methyl)benzaldehyde). These complexes were characterized by utilizing various spectroscopic protocols like NMR, FTIR, UV as well as ESI‐Mass spectrometry, elemental analysis and single crystal X‐ray diffraction studies. Their potential to bind calf thymus DNA (CT‐DNA) was tested utilizing different techniques such as UV–visible and fluorescence spectroscopy. The experiment implies that they interact with CT‐DNA via non‐intercalative mode with moderate capabilities (Kb ~ 104 M?1). On the other hand, these complexes have high capabilities to quench the fluorescence of bovine serum albumin (BSA) following the static pathway. In addition, they are active catalysts for the oxidation reaction of 3,5‐di‐tert‐butylcatechol (3,5‐DTBC) to 3,5‐di‐tert‐butylquinone (3,5‐DTBQ) under aerobic condition. From the recorded EPR signals of all complexes, it has been concluded that the oxidation reaction proceeds via ligand oriented radical pathway instead of metal based redox participation. Kinetic studies using 1 – 3 indicate that it follows Michaelis–Menten type of equation with moderate to high turnover number (kcat). Apart from these aspects, complexes 1 – 3 were screened for their cytotoxic behavior towards HeLa cells (human cervical carcinoma) and found quite active with comparable IC50 values to cisplatin.  相似文献   

9.
用模板法合成了1个大环金属铜(II)配合物[CuLCl2]·3H2O (1)和3个大环金属镍(II)配合物[NiLCl2] (2),[NiL](ClO4)2 (3)和[NiLH2](ClO4)4 (4)(L=3,10-二乙基-1,3,5,8,10,12-六氮杂十四烷),通过X-射线衍射单晶结构分析测定了它们的晶体结构。晶体结构显示:配合物12的金属离子与大环配体的4个氮原子及大环平面轴向的2个氯离子以八面体配位方式配位;配合物34的金属离子与大环配体的4个氮原子以平面正方形配位方式配位,配合物4的侧链氮原子的质子化导致侧链结构翻转,使得其侧链与大环平面共面。  相似文献   

10.
1 INTRODUCTION The synthesis of new molecular magnetic mate- rials that combine transition metal ions and pure organic radicals as ligating sites has attracted much more attention in the last few years[1~4]. Nitronyl ni- troxide radicals, independently or in combination with metal ions, have been one of the most studied systems in molecular magnetism for understanding the radical-radical or metal-radical interactions as well as for synthesizing organic ferromagnets and metal-radical magne…  相似文献   

11.
朱诗敏  黄鑫  韩勰  刘思敏 《化学学报》2022,80(8):1066-1070
由于过渡金属配合物具有独特的光物理化学性质而被广泛研究. 其中Pt(Ⅱ)配合物发生组装时会因Pt(Ⅱ)-Pt(Ⅱ)之间的距离不同而显示不同的荧光特性, 而主客体相互作用可以影响发光小分子的排列及组装. 为进一步探究主客体相互作用对Pt(Ⅱ)配合物发光性能的影响, 设计合成了不同取代的N^C^N型Pt(Ⅱ)配合物, 研究了大环主体葫芦[10]脲(CB[10])对这类配合物的识别作用及包合物的光谱性质. 核磁共振氢谱和质谱证明CB[10]可与配合物以1∶2的比例结合. 紫外-可见吸收光谱和荧光发射光谱分析表明主客体作用对该类金属配合物光谱性质有较大影响, 所形成的主客体包合物的磷光寿命及量子产率都有不同程度的变化. 研究结果表明, CB[10]可通过包结两个Pt(Ⅱ)配合物分子, 拉近铂原子之间的距离, 增强该类配合物在水相中的Pt(II)…Pt(II)相互作用和π-π相互作用, 实现水相中的长寿命磷光发射. 同时, 主客体作用对这类金属配合物的力致变色性质也有一定的影响.  相似文献   

12.
The molecular structures of the ground and the lowest triplet states for a series of Pt(II) complexes PtLCl(1)[L=6-(2-hydroxyphenyl)-2,2′-bipyridine], Pt(pp)2[pp=2-(2-hydroxyphenyl)pyridine](2), PtbpyCl2(bpy=2,2′- bipyridine)(3), and the free tridentate L ligand(4) were optimized by the density functional theory B3LYP and UB3LYP methods, respectively. On the basis of optimized geometries, the spectral properties were investigated with time-dependent density functional theory(TD-DFT). In comparison with those of complexes 2 and 3, the more rigid structure of complex 1 together with its low rate of the radiationless decay via nonemissive d-d state leads to higher photoluminescence quantum efficiency. And the phosphorescence quantum efficiency of complex 1 can be easily controlled by modifying auxiliary ligands. The introduction of fluorine ligand into complexes can effectively increase the radiation transition rate and decrease the radiationless d-d transition rate, and as a result, a novel complex PtLF(5) might be a good phosphorescent material suitable for organic electronic devices.  相似文献   

13.
Color‐tuning for phosphorescent emitters in organic light‐emitting diodes (OLEDs) across the entire visible spectrum is prerequisite to fulfil flexible full‐color displays and white solid‐state lighting. Heteroleptic 2‐phenylpyridine‐type (ppy‐type) Ir(III) and Pt(II) complexes as phosphorescent emitters have been well exploited in the electroluminescence (EL) field due to their outstanding EL performance. Furthermore, the photophysical characters of these heteroleptic Ir(III) and Pt(II) complexes are generally dominated by the nature of cyclometalating ppy‐type ligands. Accordingly, either sophisticated modification or judicious combination of different cyclometalating ppy‐type ligands will provide a wonderful platform to tune their emission color. In this personal account, we put a special emphasis on our contributions to the novel color‐tuning strategies in these heteroleptic ppy‐type Ir(III) and Pt(II) complexes. In addition, afforded by our novel color‐tuning strategies, ambipolar character or enhanced electron injection/transport (EI/ET) features can be furnished to bring high EL performances.  相似文献   

14.
Cis-[MLCl2] complexes of di-(2-pyridyl)pyrimidin-2-ylsulfanylmethane ligand (L), where M = Pd (1), and M = Pt (2) have been synthesized. Reaction of 1 with L in presence of Na[BF4] and hot acetonitrile produced the complex [PdL2](BF4)2 (3). Complexes 1-3 and ligand L have been characterized by elemental analyses, IR and NMR spectroscopy. Crystal structures of 1, 3 and L were determined by single crystal X-ray diffraction analyses, showing nonplanar structures with the pyridinic rings twisted around the bridging carbon and the ipso carbon bonds. 1 and 3 displayed a bidentate coordination of L to the palladium atom with the formation of six-membered chelate rings, where the local geometry at palladium atom was distorted square planar. In 3 the palladium atom was coordinated to two dipyridyl ligands through two of the pyridinic nitrogen atoms to form a cationic complex stabilized by two tetrafluoroborate counter-ions.  相似文献   

15.
Kinetics of interaction between [Pt(pic)(H2O)2](ClO4)2, 2 (where pic = 2-aminomethylpyridine) with the selected ligands DL-methionine (DL-meth) and DL-penicillamine (DL-pen) have been studied spectrophotometrically in aqueous medium separately as a function of [2] as well as [ligand], pH and temperature at constant ionic strength. The association equilibrium constants (KE) for the outer sphere complex formation have been evaluated together with the rate constants for the two subsequent steps. Activation parameters (enthalpy of activation ΔH and entropy of activation ΔS) were calculated from the Eyring equation. An associative mechanism of substitution is proposed for both reactions on the basis of the kinetic observations, evaluated activation parameters, and spectroscopic data. Structural optimizations, HOMO-LUMO energy calculation, and Natural Bond Orbital (NBO) analysis of 24 were carried out with Density Functional Theory. Bonding mode of thiol and thio-ether is confirmed by spectroscopic analyses and NBO calculation. Cytotoxic properties of 24 were explored on A549 carcinoma cell lines; DNA-binding properties of the complexes were also investigated by gel electrophoresis.  相似文献   

16.
IntroductionIthasbeenfoundfrequentlyinhydrolasesthattwoormoremetalionsareassembledinverycloseproximitytothecarboxylatesidechainsofaminoacidresiduesatenzymeac tivesitestocarryouttheirbiologicalfunctions.1Metalsem ployedinhydrolasesincludemagnesium ,manganese ,iron ,cobalt,nickelandzinc .1Onekindofhydrolases,themethio nineaminopeptidasefromE .coil (EcMAP) 2 andPyrococcusfuriosus (PfMAP) 3bothrequiretwoCo2 + ionsfortheiractiv ity ,whereastheirstructuresaredifferent.Thediversestructuresandmet…  相似文献   

17.
多吡啶钌配合物作为DNA结构探针的研究   总被引:13,自引:2,他引:13  
本文对多吡啶钌配合物作为DNA荧光或结构探针的研究背景、研究技术及其特点、钌配合物与DNA的键合模式及其结合力大小的影响因素、钌配合物与DNA键合的异构选择性及不同键合速率、非放射性核酸标记及DNA分子光开关等方面进行了简要述评  相似文献   

18.
The thermal decomposition of the Pt(II) complexes with cyclobutane-and cycloheptanespiro-5′-hydantoins were studied by TG and DTA techniques. The Pt(II) complex with cyclobutanespiro-5′hydantoin (PtCBH) was stable up to 115°C (388 K) and Pt(II) complex with cycloheptanespiro-5′-hydantoin (PtCHTH) was stable up to 150°C (423 K). After the thermal decomposition of PtCBH the solid residue was platinum, while the decomposition of PtCHTH gave a mixture of platinum carbides (PtC2, Pt2C3).  相似文献   

19.
蒋才武 《化学学报》2004,62(7):692-696
合成了两个新型不对称三齿多吡啶配体 ,3 ( 1,10 菲咯啉基 2 ) 1,2 ,4 三唑 (PHT) ,3 ( 1,10 菲咯啉基 2 ) 5 甲基 1,2 ,4 三唑 (PHMT) ,及其混配配合物 [Ru(tpy) (PHT) ] 2 + (Ru1)和 [Ru(tpy) (PHMT) ] 2 + (Ru2 ) ,通过元素分析、FAB MS ,ES MS ,1HNMR ,IR ,UV vis ,发射光谱和电化学对它们进行了表征 .运用电子吸收光谱、竞争性结合实验和粘度测试等方法研究了配合物与DNA的作用机理 ,结果显示它们均是通过静电作用与DNA结合 ,且Ru2与DNA的作用比Ru1与DNA的作用更强 .  相似文献   

20.
The purpose of this study was to identify new metal-based anticancer drugs; to this end, we synthesized two new copper(II) complexes, namely [Cu(ncba)4(phen)] (1) and [Cu(ncba)4(bpy)] (2), comprised 4-chloro-3-nitrobenzoic acid as the main ligand. The single-crystal XRD approach was employed to determine the copper(II) complex structures. Binding between these complexes and calf thymus DNA (CT-DNA) and human serum albumin (HSA) was explored by electronic absorption, fluorescence spectroscopy, and viscometry. Both complexes intercalatively bound CT-DNA and statically and spontaneously quenched DNA/HSA fluorescence. A CCK-8 assay revealed that complex 1 and complex 2 had substantial antiproliferative influences against human cancer cell lines. Moreover, complex 1 had greater antitumor efficacy than the positive control cisplatin. Flow cytometry assessment of the cell cycle demonstrated that these complexes arrested the HepG2 cell cycle and caused the accumulation of G0/G1-phase cells. The mechanism of cell death was elucidated by flow cytometry-based apoptosis assays. Western blotting revealed that both copper(II) complexes induced apoptosis by regulating the expression of the Bcl-2(Bcl-2, B cell lymphoma 2) protein family.  相似文献   

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