二茂铁基-双酮锌配合物的合成、电化学活性及多光子吸收

合成了具有推-拉电子(D-A)构型的二茂铁基双酮配体(L)及配合物(NHEt_3)[Zn(L)_3]。晶体结构分析表明,二茂铁双酮脱去一个质子,以烯醇式与Zn~(2+)配位,得到-1价的二茂铁双酮基锌配合物。循环伏安和原位红外电化学方法研究发现,(NHEt_3)[Zn(L)_3]发生了两步氧化和一步还原过程:随着氧化过程中电位的增加,其中1个二茂铁(Fc)配体被氧化成Fc~+,形成D-A不对称结构模式;随着氧化的继续,2个Fc配体也被氧化,3个Fc~+与锌中心仍成D-A结构模式,最后将Fc~+一步还原成Fc。理论计算结果表明,配合物的电子离域程度高,有利于电荷流动。非线性光学实验结果显示,该配合物在近红外区具有大的双/三光子吸收效应和三阶非线性光学极化率。     

二硫代氨基甲酸盐过渡金属配合物的合成及三阶非线性光学性质研究

以对苯二胺为原料合成了二硫代氨基甲酸盐过渡金属［Ｎｉ（Ⅱ）,Ｐｄ（Ⅱ）,Ｐｒ（Ⅱ）］配合物及其它相应脱质子产物卡宾二硫代胺基甲酸盐配合物．通过元素分析,ＩＲ,ＵＶ测试表征．对该系列配合物用四波混频方法,研究了它们的三阶非线性光学性质．结果表明,平面型二硫代甲酸盐配合物有较强的三阶非线性光学效应．并且它们脱去质子形成的配合物共轭体系更大,其三阶非线性光学效应明显提高．     

C60腈胺类衍生物的合成及三阶非线性光学性质

C60的三阶非线性光学性质的研究是近年来富勒烯物理化学性质的研究热点之一[1].研究显示,尽管C60具有三维共轭的π电子体系,其本身并不具有大的三阶非线性系数[2,3].但由于C60分子具有较低的三重简并LUMO能级,显示出较强的电负性,能够与适当的给电子体形成相应的电荷转移体系,其三阶非线性系数可提高一至两个量级[3-6].本文通过合成C60的腈胺和双聚腈胺衍生物及其Fe(Ⅲ)配合物,对其三阶非线性光学性质及电荷转移作了初步探讨.     

二茂铁亚甲基三氮唑配合物的合成、晶体结构及性能研究

以二茂铁亚甲基三氮唑为配体,通过与金属离子的自组装得到了两个新的二茂铁基功能配合物：[Cd(tmf)2(SCN)2]n (1) 和 [Ni(tmf)4(SCN)2] (2) (tmf =二茂铁亚甲基三氮唑)。其中,配合物1呈一维链状结构;配合物2是一个通过氢键作用而形成的二维超分子。三阶非线性光学性质测试结果表明,配合物1（n2 = 2.11 × 10-11 esu）和2（n2 = 1.92 × 10-11 esu）的三阶非线性光学折射效应与配体tmf（n2 = 2.49 ×10-11 esu）接近,说明配合物1和2的三阶非线性光学性质主要受配体控制。循环伏安法(CV)测试结果显示,这两个配合物在电极上的氧化还原过程是受扩散控制的。计时电流法(CA)和计时电量法(CC)测得配合物1的扩散系数比配合物2的扩散系数小。     

四吡咯环状化合物的光物理和三阶非线性光学性质的研究

本论文在设计合成一系列四吡咯环状化合物的基础上,运用多种光谱手段研究周边取代对包括酞菁、三明治型酞菁、芴取代卟啉与氮杂卟啉在内的四吡咯环状化合物及其配合物的光物理性质和受355nm的光激发后所经历的光物理过程;研究不同结构因素对四吡咯环状化合物及其配合物的光物理性质的影响;用光限幅和Z-扫描方法检测四吡咯环状化合物的三阶非线性光学响应,研究其三阶非线性光学性质的来源,计算衡量其光限幅性质和三阶非线性光学性质的参数,并分析其产生的原因、结构与非线性光学性质的关系和影响其强弱的因素.     

双二茂铁-钯配合物的合成，结构和电化学

本文讨论了由二茂铁的C-H…π作用组装的具有类环己烷结构的氨基硫脲钯金属配合物的结构和电化学性能。晶体结构中钯原子以顺式平面正方形的构型分别与两个氨基硫脲配体配位，两个配体中的二茂铁基团位于钯原子同一侧，每个二茂铁与相邻分子中的二茂铁基团通过环戊二烯基环间的C-H…π作用形成由类环己烷结构连结的二维网状结构。对钯的配合物及相关的镍和锌配合物的电化学研究表明，平面正方型的钯和镍可以有效的传递两个茂铁间的氧化-还原性能。     

钌(Ⅱ)多吡啶配合物的合成、表征及其三阶非线性光学性质研究

合成了三种含咪唑并[4,5-f]邻菲莫咯啉(IP)的钌(Ⅱ)配合物，通过元素分析、FAB-MS、^1HNMR、UV-vis和电化学对它们进行了表征。运用Z-扫描的实验方法研究了钌(Ⅱ)配合物的三阶非线性折射率n~2和非线性吸收系数α~2，并由此计算出它们的三阶非线性系数χ^(^3^)和分子超极化率γ。分析了分子结构对其三阶非线性光学性质的影响。     

中心对称吡嗪衍生物电子光谱和三阶非线性光学性质的理论计算研究

采用量子化学abinitio HF和半经验ZINDO-SOS方法计算了吡嗪及其衍生物的电子光谱和三阶非线性光学系数.结果表明,中心对称的吡嗪衍生物随着体系共轭链的增长,最大吸收谱线波长增大,前线轨道能级差减小,体系的三阶非线性光学系数增大;引入取代基后可改变其三阶非线性光学性质.在相同骨架中引入吸电子基团-NO₂形成A-π-A共轭结构,其三阶非线性光学系数比引入供电子基-NH₂的体系大.     

二到七环多苯稠合物的三阶非线性光学效应的理论 研究

利用含组态相互作用的INDO－SDCI和态求和(SOS)方法,计算二到七环的稠合多苯化合物的三种不同物理过程的频率相关的三阶非线性光学系数。讨论不同光物理过程的色散行为及π电子离域程度对非线性光学效应的影响,同时给出计算简并四波混合(DFWM)的非线性光学系数的具体表达式。计算结果表明,三阶非线性光学系数随着环沿一维方向扩展而急剧增加,π-π^*电荷转移对多苯稠合物的三阶非线性极化率起主要贡献。     

一个新的二茂铁-钴四核双螺旋配合物的合成，结构和电化学性质研究

利用1，1′-双羧酸二茂铁为配体设计合成了一个新的二茂铁-钴四核双螺旋配合物并研究了其电化学性能。该配合物具有一个垂直于其螺旋轴的C₂对称性，四个金属中心形成一个边长为5.4?菱形结构。二茂铁配体的两个羧基以顺式结构与两个金属中心配位。电化学研究表明作为桥联基团的金属钴配位中心能够有效传递二茂铁基团间的氧化还原性能。     

Syntheses, electrochemistry and crystal structure studies of novel cis-configuration biferrocene trinuclear complexes

The syntheses and characterization of novel biferrocene trinuclear complexes for Schiff base ligand, S-methyl-N-(ferrocenyl-1-methyl-methylidene)dithiocarbazate (hereafter abbreviate as HL), are described. X-ray diffraction studies established the structures of the palladium complex, PdL₂2 and the copper complex, CuL₂3. The geometry of Pd(II) in 2 is close to square planar and in novel cis-configuration with two ferrocene moieties in the same side, while that of Cu(II) in 3 is close to tetrahedral configuration. Electrochemical measurements suggest that the distorted square planar configuration of the Ni(II) and Pd(II) moieties, can effectively transmit the redox effects of the ferrocene moieties, while the distorted tetrahedral configuration of Cu(II) complex can not transmit the redox effects.     

An unsymmetrical tripodal ligand with an N2OS donor set: coordination chemistry with nickel(II)ions and aerial oxidation to the sulfinate complex

The synthesis of the previously unknown tripodal ligand H4-1 is reported. The tetradentate ligand is equipped with a completely unsymmetrical N2OS donor set. It reacts with Ni(OAc)2. 4H2O or Ni(ClO4)2.6H2O to give the multinuclear nickel(II) complexes [Ni(H-1-Imin)(OAc)]2 (2) (which contains a coordinated Schiff base obtained by reation of the primary amine with the acetone solvent) and [Ni3(H3-1)(H2-1)2]-ClO4.H2O.3 MeCN (3), respectively. A solution of 3 in DMF is readily oxidized upon exposure to air or by aqueous H2O2 to yield [Ni(H2-1-sulfinate)]2. 2MeOH (4). The molecular structures of 2-4 have been determined by X-ray diffraction. Complex 2 exhibits a strongly distorted, octahedral coordination geometry around each nickel(II)ion. The primary amino group of the ligand in this case reacted with the solvent acetone to yield a Schiff base which is coordinated to the metal center. The molecular structure of the trinuclear complex cation in 3 consists of two subunits: a nickel atom with a square-planar N2S2 coordination geometry and two other nickel atoms with a trigonal-bipyramidal N2O2S coordination environment. The dinuclear complex 4 shows distorted octahedral geometry around each nickel(II) ion. The thiolato groups of the ligands are oxidized to sulfinato groups which are O,O-bound to the nickel center. This coordination mode is unusual for nickel sulfinate complexes.     

The Preparation, Characterization and Biological Activity of Palladium(II) and Platinum(II) Complexes of Tridentate NNS Ligands Derived from S-methyl- and S-benzyldithiocarbazates and the X-ray Crystal Structure of the [Pd(mpasme)Cl] Complex

New complexes of general formula, [M(NNS)Cl] (M = Pd^II, Pt^II; NNS = anionic forms of the 6-methyl-2-formylpyridine Schiff bases of S-methyl- and S-benzyldithiocarbazates) have been prepared and characterized by a variety of physico-chemical techniques. Based on conductance and spectral evidence, a square-planar structure is assigned to these complexes. The crystal and molecular structure of the [Pd(mpasme)Cl] complex (mpasme=anionic form of the 6-methyl-2-formylpyridine Schiff base of S-methyldithiocarbazate) has been determined by X-ray diffraction. The complex has a distorted square-planar geometry with the ligand coordinated to the palladium(II) ion via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom; the fourth coordination position around the palladium(II) ion is occupied by the chloride ligand. The distortion from a regular square-planar geometry is ascribed to the restricted bite angle of the ligand. Both the Schiff bases exhibit strong cytotoxicity against the human ovarian cancer (Caov-3) cell lines, the S-methyl derivative being two times more active than the S-benzyl derivative. The [Pt(mpasme)Cl] complex is moderately active but the palladium(II) complex is weakly active against this cancer. None of the complexes of Hmpsbz are active against Caov-3. The Schiff base, Hmpasme exhibits moderate activity against the bacteria, MRSA, P. aeruginosa and S. typhimurium but is inactive against B. subtilis. Coordination of the ligand with palladium(II) substantially reduces its activity. The Schiff base, Hmpasbz and its palladium(II) and platinum(II) complexes are inactive against these bacteria. The Schiff bases and their palladium(II) and platinum (II) complexes are inactive against the pathogenic fungi, C. albican, Aspergillus ochraceous and Saccharomyces cerevisiae.     

Synthesis,spectroscopic, electrochemical and structural characterization of Cu(II) complexes with asymmetric NN′OS coordination spheres

A set of four Cu(II) complexes, [Cu(cdnapen)], [Cu(cdnappd)], [Cu(cdMenappd)] and [Cu(cdMeMeOsalpd)], derived from Schiff base ligands with an asymmetric NN′OS coordination sphere have been synthesized. The molecular and the crystal structures have been determined by X-ray diffractometry. The structural results confirm that the complexes are tetra coordinated. The copper (II) ion coordinates to two nitrogen atoms from the imine moiety of the ligand, a sulfur atom from the methyl dithiocarboxylate moiety and a phenolic oxygen atom. The complexes show an unusual tetrahedral distortion to the square-planar geometry around the metal centre in spite of the pseudomacrocyclic skeleton of the ligand. The complexes were further characterized by cyclic voltammetry and electron paramagnetic resonance spectroscopy. The degree of tetrahedral distortion of the complexes appears to be dependent on the number of carbon atoms of the aliphatic bridge and the nature of the coordinating atoms.     

Synthesis,characterization and bio-activity of a bidentate NS Schiff base of S-allyldithiocarbazate and its divalent metal complexes: X-ray crystal structures of the free ligand and its nickel(II) complex

Transition metal complexes ML₂ (2–6) [where M = Ni(II), Cu(II), Zn(II), Cd(II), Pd(II) and HL = allyl-2-(4-benzyloxyphenylmethylene)hydrazine carbodithioate (1)] have been prepared by the reaction of the ligand with metal ions in 2:1 molar ratio and characterized by physicochemical techniques and spectroscopic methods. The crystal structures of the free ligand and its nickel(II) complex 2 have been determined by X-ray diffractometry. The ligand exists in its thione tautomeric form both in solution and in the solid state. In complex 2, square-planar coordination of nickel(II) was achieved by two chelating ligand moieties coordinating through the azomethine nitrogen and the deprotonated thione sulphur atom. Based on the crystal structures of analogous dithiocarbazate species, a square-planar geometry was assumed for the copper(II) and palladium(II) complexes, and a tetrahedral coordination sphere for the zinc(II) and cadmium(II) derivatives. The in vitro bactericidal activity suggests that the palladium(II) complex is strongly active against two bacteria. The cadmium(II) complex is moderately cytotoxic with an LC₅₀ value of 409 μg/ml, but less active than gallic acid, LC₅₀ = 78 μg/ml.     

Structural elucidation of o-vanillin isonicotinoyl hydrazone and its metal complexes

Summary A new series of complexes with the tridentate dibasic Schiff base ligand o-vanillin isonicotinoyl hydrazone (o-VINH) were prepared and characterized by i.r., ¹H n.m.r. and electronic spectral studies, magnetic susceptibility measurements and t.g.a. The disappearance of low field signals due to OH, NH protons at 10.23 and 9.31 p.p.m. and downfield shift of the –CH=N proton signal at 8.17 p.p.m. in the n.m.r. spectrum confirms the involvement of these groups in coordination. Both t.g.a. and i.r. spectral data show evidence for one molecule of coordinated H₂O. These results taken in conjunction with electronic spectral data allow assignation of tetrahedral geometry for manganese(II), nickel(II) and palladium(II) complexes but a square planar configuration to cobalt(II), copper(II) amd zinc(II) complexes.     

Investigation of DNA Binding Interaction of Newly Synthesized Nickel(II) and Palladium(II) Complexes Containing Ferrocenyl Schiff Base Ligand

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.     

Ligational behavior of a bidentate coumarin derivative towards CoII,NiII, and CuII: synthesis,characterization, electrochemistry,and antimicrobial studies

A series of new Co(II), Ni(II), and Cu(II) complexes of Schiff base derived from coumarin have been prepared and characterized by analytical and spectral methods. The Schiff base is synthesized by the condensation of 2,6-diaminopyridine and 3-acetylcoumarin in 1 : 1 stoichiometric ratio. All complexes have 1 : 1 metal : ligand ratio except the nickel complex, where it was found to be 1 : 2. UV-Vis spectra and magnetic moment studies confirm the existence of tetrahedral and octahedral geometries around cobalt(II) and nickel(II) metal ions, respectively, but copper(II) chloride/nitrate/sulfate complexes have square-planar geometry and copper(II) acetate complex is distorted octahedral. ESR spectra of copper complexes at room temperature and liquid nitrogen temperature were tetragonal. All the complexes were found to be more active against bacteria except Ni(II) complex; only CuLSO₄ and CuL(CH₃COO)₂ have shown the enhanced activity against fungi.     

Synthesis, characterization and biological activities of Cu(II), Co(II), Mn(II), Fe(II), and UO2(VI) complexes with a new Schiff Base hydrazone: O-hydroxyacetophenone-7-chloro-4-quinoline hydrazone

The Schiff base hydrazone ligand HL was prepared by the condensation reaction of 7-chloro-4-quinoline with o-hydroxyacetophenone. The ligand behaves either as monobasic bidentate or dibasic tridentate and contain ONN coordination sites. This was accounted for be the presence in the ligand of a phenolic azomethine and imine groups. It reacts with Cu(II), Ni(II), Co(II), Mn(II), UO(2) (VI) and Fe(II) to form either mono- or binuclear complexes. The ligand and its metal complexes were characterized by elemental analyses, IR, NMR, Mass, and UV-Visible spectra. The magnetic moments and electrical conductance of the complexes were also determined. The Co(II), Ni(II) and UO(2) (VI) complexes are mononuclear and coordinated to NO sites of two ligand molecules. The Cu(II) complex has a square-planar geometry distorted towards tetrahedral, the Ni(II) complex is octahedral while the UO(2) (VI) complex has its favoured heptacoordination. The Co(II), Mn(II) complexes and also other Ni(II) and Fe(III) complexes, which were obtained in the presence of Li(OH) as deprotonating agent, are binuclear and coordinated via the NNNO sites of two ligand molecules. All the binuclear complexes have octahedral geometries and their magnetic moments are quite low compared to the calculated value for two metal ions complexes and thus antiferromagnetic interactions between the two adjacent metal ions. The ligand HL and metal complexes were tested against a strain of Gram +ve bacteria (Staphylococcus aureus), Gram -ve bacteria (Escherichia coli), and fungi (Candida albicans). The tested compounds exhibited high antibacterial activities.     

Synthesis,spectral characterization,X-ray crystal structure,electrochemical studies,and DNA interactions of a Schiff base pro-ligand and its homobimetallic complexes containing the cysteamine moiety

A Schiff base, N,N′-(3,4-dithiahexane-1,6-diyl)bis(5-methylsalicylideneimine), was synthesized and characterized by X-ray crystallography. Dimeric complexes of nickel(II), palladium(II), and vanadium(IV) were synthesized by the reactions of the Schiff base with nickel(II) acetate, palladium(II) acetate, and vanadyl acetylacetonate in 1:1 molar ratio. In all three complexes, the thiol group was deprotonated and coordinated to the metal. The X-ray structure of the Schiff base showed that in the crystalline form, the SH groups were oxidized to the corresponding disulfide. In the dimeric complexes, coordination took place through the azomethine nitrogen, enolic oxygen, and sulfur atoms. The metal-to-ligand ratio was 1:1, and molar conductance data revealed that the metal complexes were nonelectrolytes. The free Schiff base and its complexes showed photoluminescence in methanol at room temperature. The redox behavior of the compounds was studied by cyclic voltammetry in DMF, which showed both quasi-reversible and irreversible processes. The interaction of the complexes with DNA was investigated by electronic absorption spectroscopy.