Triboluminescent Complexes of Rare Earth Ⅱ.Mixed-ligand Complexes of Eu^(3+) with Thenoyltrifluoroacetone and Pyridine-N-Oxide or its Substitutive Derivatives

Five triboluminescent mixed-ligand complexes of Eu^(3+)with thenoyltrifluoroacetone(TTA)and pyridine-N-oxide or its substitutive derivatives have been prepared.They are all pale yellow crystalline com- pounds with the formula of Eu(TTA)_3·L(L=py NO.2-pie NO,3-pie NO,4-pic NO,bipy N_2O_2).Their physico-chemical properties have been studied with conductometry,UV and IR absorption and fluorescence spectroscopy.Once the complexes are touched or rubbed by a glass rod,they emit strong red triboluminescent light which is similar to the characteristic fluorescence of Eu^(3+).

Spectra and DNA-binding Properties of Two Novel Mixed-ligand Complexes Containing Organosulfonate

Two novel mixed-ligand complexes, [M（phen）2（ans）2]·H2O （M = Cd（Ⅱ） 1, Zn（Ⅱ） 2; phen is 1, 10-phenanthroline, and ans is 4-aminonaphthalene-1-sulfonate）, were obtained from the reaction of 1, 10-phenanthroline, sodium 4-aminonaphthalene-1-sulfonate tetrahydrate and acetate in mixed solvents. Interaction of the complexes with calf thymus DNA （ctDNA） were investigated using UV-vis absorption spectra, luminescence titrations, steady-state emission quenching by [Fe（CN）6]4 , DNA competitive binding with ethidium bromide （EB） and viscosity measurements. The experimental results indicate that there exist two interaction modes between the complexes and DNA, namely the electrostatic interaction and intercalation, with the binding constants of 1.82 × 10^5 M-1 for 1 and 4.78 ×10^4 M^- 1 for 2 in buffer of 50 mM NaCl and 5 mM Tris-HCI （pH 7.0）.

Intramolecular stacking interaction in mixed-ligand complexes containing ATP4-and aromatic N-heterocyclic ligands

The stability constants of the binary ML2+ and ternary M(ATP)L2? complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+, have been determined by potentiometric pH titration in aqueous solution at I=0.1 mol/L (NaClO4), T=25°C. The stability of the ternary complexes characterized by ΔlogKM=logKM(ATP)LM(ATP)L- logKMML corresponding to the equilibrium M(ATP)2? + ML2+ = M(ATP)L2? + M2+ in higher than what would be expected on statistical grounds. The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4–. 1H NMR studies of Zn2+/ATP4?/L confirm the presence of stacking in the ternary complexes. It is concluded that the strength of the intramolecular stacking interaction ia dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge. Possible implications an discussed briefly.

Mixed-Ligand Ni(Ⅱ), Co(Ⅱ) and Fe(Ⅱ) Complexes as Catalysts for Esterification of Biomass-Derived Levulinic Acid with Polyol and in Situ Reduction via Hydrogenation with NaBH_(4)

Synthesizing polyol-based ester from biomass feedstocks for the preparation of biolubricant overcomes the dependence on petroleum oil usage.Albeit biomass-derived bio-oil is an alternative for the production of polyol ester,upgrading is essential prior to use as biolubricant.Levulinic acid(LA),obtained from bio-oil was applied for the catalytic esterification with two polyols,e.g.,trimethylolpropane(TMP)and pentaerythritol(PE),in the presence of mixed-ligand Ni(Ⅱ),Co(Ⅱ),and Fe(Ⅱ)complexes as catalyst.New mixed-ligand coordination complexes with empirical formula;[Ni(Phe)(Bpy)Cl].H2O,[Co(Phe)(Bpy)Cl].H2O,and[Fe(Phe)(Tyr)Cl].H2O were synthesized by the reaction of ligands[L-phenylalanine(Phe),4,4'-bipyridine(Bpy),and L-tyrosine(Tyr)]with metal chloride salts and characterized by elemental analysis,magnetic susceptibility,FTIR,TGA/DTA,powder-XRD,and SEM techniques.This study aims to investigate the catalytic activities of the complexes via esterification reaction of levulinic acid with trimethylolpropane and pentaerythritol.In addition,these catalysts were further employed for the in situ hydrogenation of levulinate esters via NaBH_(4) at room temperature upon refluxing.Indeed,the iron(Ⅱ)complex was more potential,exhibiting its efficiency as a homogeneous catalyst for esterification-hydrogenation reaction for synthesizing ester-based oils.

Synthesis, Characterization and Antimicrobial Screening Mixed-Ligand Cu(II) and Zn(II) Complexes;DNA Binding Studies on Cu(II) Complex

Several mixed ligand Cu(II), Zn(II) complexes using (benzylidenethiourea) (obtained by the condensation of benzaldehyde and thiourea) as the primary ligand and (acetamide or thioacetamide) as an additional ligand were synthesized and characterized analytically and spectroscopically, magnetic susceptibility and molar conductance measurements ,as well as by UV-Vis. and IR spectroscopy. The interaction of the complexes with calf thymus (CT)DNA was studied using absorption spectra, while the concentration of DNA in gel electrophoresis remained constant at 10 μl. They exhibit absorption hypochromicity increased during the binding of the complexes to calf thymus DNA. The complexes show enhanced antimicrobial activities complexes with the free ligand. A theoretical treatment of the formation of complexes in the gas phase was studied, this was done using the HYPERCHEM-6 program for the Molecular mechanics and Semi-empirical calculations.

Theoretical Studies on Structures and Spectroscopic Properties of Highly Efficient Phosphorescent [Ru（terpy）（phen）X]＋ Complexes

The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru（II） complexes [Ru（terpy）（phen）X]＋ （terpy=2,2＇,6＇,2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH （1）, X=Cl （2）, X-CN （3）） were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π＊（terpy） type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz （Ru）＋Tr/p（X）--π＊ （terpy） transition with MLCT/XLCT （metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer） character, whereas that of 3 at 529 nm is related to a dyz （Ru）＋π（terpy）-π＊ （terpy） transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm （1）, 913 nm （2）, and 838 nm （3） have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru（II） complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.

A Trinuclear Ni(Ⅱ) Mixed-ligand Complex Containing Pentadentate N-butyl-salicylhydrazide and Monodentate Imidazole:Synthesis, Characterization and Crystal Structure

A novel trinuclear nickel（II） complex [Ni3（bushz）z（Himdz）2（H20）2].2DMF （1, bushz = N-butylsalicylhydrazide, Himdz = imidazole, DMF = N,N-dimethyl-forrnamide） has been synthesized and characterized by X-ray single-crystal diffraction characterization. Complex 1 crystallizes in the monoclinic system, space group P2 1/c with a = 7.706（7）, b = 14.882（6）, c = 18.639（6） A, β = 108.08（2）°, V= 2032（1） A3, Dc = 1.525 g/cm3, Mr = 932.95, Z= 2, F（000） = 972,μ = 1.442 mm-1, the final R = 0.0359 and wR = 0.0771. The three nickel（II） atoms in 1 are arranged in a strictly linear structure and exhibit alternating square-planar and octahedral geometries. The complex is connected to form a supramolecule with an infinite three-dimensional network through intermolecular hydrogen bonds. The electrochemical studies reveal that redox of Ni3＋/Ni2＋ in the complex is a quasi-reversible process. The thermal stability of the title complex was also studied.

Studies of the Intramolecular Aromatic-ring Stacking Interactions in the Ternary Platinum(Ⅱ) Complexes

The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.

Synthesis,Structure and Luminescent Properties of Polymeric Copper(Ⅰ) Halide Complexes Bearing Phosphine and N-donor Bridging Ligands

Three polymeric copper（Ⅰ） halide complexes beating phosphine and N-donor bridging ligands, [（PPh3）2Cu2（μ-Br）2（μ-4,4＇-bipy）]∞ 1 （bipy = bipyridine）, [（PPh3）2Cu2（μ-Br）2（μ- bpe）]∞ 2 （bpe = trans-1,2-bis（4-pyridyl）ethene） and [（PPh3）2Cu2（μ-Cl）2（μ-bpe）]∞ 3, were synthesized by the multilayer diffusion method, and the structures were refined by single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P1^- with a = 9.122（3）, b = 9.322（3）, c = 13.201（4） A, α = 106.440（4）, β= 105.965（5）, γ= 94.167（5）°, V = 1021.3（6） A^3, Mr= 967.62, Z = 1, De= 1.573 g/cm^3, F（000） = 486, μ = 3.111 mm^-1, the final R = 0.0383 and ωR = 0.0960 for 2792 observed reflections （I 〉 2σ（I））. Complex 2 crystallizes in triclinic, space group P1^- with a = 9.420（3）, b = 10.209（4）, c = 12.407（4） A, α = 104.136（6）, β = 108.132（5）, γ= 95.338（6）°, V = 1081.0（7） A^3, Mr= 496.83, Z = 2, Dc= 1.526 g/cm^3, F（000） = 500, μ = 2.941 mm^-1, the final R = 0.0445 and ωR = 0.1117 for 3251 observed reflections （I 〉 2σ（I））. Complex 3 crystallizes in triclinic, space group P1^- with a = 8.32（1）, b = 11.53（2）, c = 13.94（3） A, α = 109.57（3）, β= 93.85（3）, γ= 97.28（3）°, V= 1242（4） A^3, Mr= 1074.59, Z = 1, Dc = 1.436 g/cm^3, F（000） = 548, μ = 1.279 mm^-1, the final R = 0.0786 and ωR = 0.1586 for 2266 observed reflections （I 〉 2σ（I））. The complexes exhibit intensive solid-state photoluminescence tentatively assigned to an admixture of triplet intraligand （IL） and metal-to-ligand charge-transfer （MLCT） excited state.

Spectroscopic Investigation of the Complex Formation of Niobium Using 2,6-Dithiolphenol and Aminophenols

A new, simple, precise, selective and sensitive method for the extraction and spectrophotometric determination of niobium has been described. Mixed-ligand complexes of Niobium (V) with 2,6-dithiolphenol (DTP) and aminophenols (AP) have been studied by spectrophotometry. Extraction of mixed-ligand complexes is maximal at pH 3.6 - 5.0. The optimal conditions for the formation and extraction of mixed-ligand compounds have been found. The molar ratio of the reacting species was 1:2:2 (Nb:DTP:AP). The Beer’s law was applicable in the range of 0.05 - 4.0 μg/ml. The method is free from common interferences. A procedure has been developed for extraction-spectrophotometric determination of Niobium in steel.

Ln（TDBM）_4［C_5H_（11）N］H配合物的合成与性质研究

本文合成了单硫代－二苯甲酰甲烷（ＨＴＤＢＭ）和三价稀土离子及路易斯碱（Ｑ）的Ｌｎ（ＴＤＢＭ）４ＱＨ型配合物（Ｌｎ为除Ｃｅ外的Ｌａ－Ｌｕ；Ｑ＝六氢吡啶ＣＨ２（ＣＨ２）４ＮＨ）．测定了它们的组成、摩尔电导、红外光谱、紫外可见光谱及热重分析，讨论了它们的一些性质．观察到配体通过Ｓ原子和Ｏ原子与Ｌｎ３＋离子配位，且Ｌｎ—Ｏ键强于Ｌｎ—Ｓ键．配合物的热分解分三步进行，第一步失去六氢吡啶，第二步失去一个ＴＤＢＭ，第三步失去三个ＴＤＢＭ．

二苯基硫脲铜(Ⅰ)配合物的合成、晶体结构及性质研究

采用简单的方法原位还原铜(Ⅱ)为铜(Ⅰ),合成了二苯基硫脲铜(Ⅰ)配合物C32H38ClCuN6O2S2,通过IR和元素分析等手段对其进行表征,并用X射线单晶衍射确定了其晶体结构。该配合物晶体属单斜晶系,P21/c空间群,晶胞参数为a=0.957 4(5)nm,b=3.210 7(17)nm,c=1.222 8(7)nm;β=111.877(8)°,V=3.488(3)nm3,Z=4,Dc=1.336 mg/m3,F(000)=1 464,最终结构偏差因子R1=0.047 5,ωR2=0.130 7。基于多种分子间氢键的作用,分子在固相中堆积成三维超分子结构。同时研究了此配合物的光谱性质、热稳定性及电化学行为。

一种新型镍-顺丁烯二酸混配配合物的制备与性质研究

在室温下,顺丁烯二酸(mal)、2,2'-联吡啶(bipy)和硝酸镍反应得到一个未见报道的顺丁烯二酸过渡金属混配配合物:[Ni(bipy)(H2O)3(mal)]·H2O,并培养得到其晶体。用元素分析和红外光谱进行了表征,单晶X-射线衍射技术测定了的晶体结构;热分析方法研究了配合物的热稳定性。

红菲绕啉对苯乙酮酸铕(Ⅲ)配合物热稳定性及荧光性能的影响

以苯乙酮酸(HL)和红菲绕啉(Bath)为配体,合成了两种Eu(Ⅲ)配合物。采用元素分析、等离子体原子发射光谱(ICP)、FT-IR和1H NMR对配合物的组成及结构进行了表征。研究了两种配合物的热稳定性和荧光性能(激发光谱、发射光谱、荧光寿命和量子产率)。结果表明:两种配合物的分子式分别为Eu L3·x H2O和Eu L3Bath。当引入第二配体Bath,配合物的起始分解温度由219℃(Eu L3·x H2O)提高到了293℃(Eu L3Bath),改善了配合物的热稳定性;同时,配合物荧光性能显著增强,主要表现在荧光发射强度明显增强,量子产率提高了9.02%,荧光寿命延长了3.01 ms。

Stacking interaction in metal complexes with compositions of DNA and heteroaromatic N-bases

The current development in the intramolecular aromatic-ring stacking interactions in the complexes with compositions of DNA and heteroaromatic N-bases has been reviewed to a great extent, especially the significant contributions in several important systems about ternary mixed-ligand complexes, including nucleotide-metal ion-po-lyaromatic amine, amino acid-metal ion-polyaromatic amine, nucleotide-metal ion-pyridine-like aromatic amine, nucleo-tide-metal ion-amino acid, nucleotide-metal ion-nucleic acid base, nucleic acid base-metal ion, and the important factors affecting the intramolecular aromatic-ring stacking interac-tions in the complexes. Based on the study of stacking inter-action in the complexes, the mechanism of interaction be-tween DNA molecules and complexes of heteroaromatic N-bases has been established, which is crucial for the design and synthesis of the complexes acting as molecular devices of DNA.

Two Carboxylato-bridged Binuclear Cobalt(Ⅱ) Complexes Pillared Coligands: Synthesis, Structures and Magnetic Properties

By adopting mixed-ligand strategy,two Co(Ⅱ)coordination polymers,[Co(phda)(itmb)(H2O)2]n(1)and[Co(phda)(Hpytz)]n(2)(H2phda=1,2-phenylenediacetate,itmb=1-(imidazo-1-ly)-4-(1,2,4-triazol-1-yl methyl)benzene and Hpytz=3,5-di(4-pyridyl)-1,2,4-triazolate),were hydrothermally synthesized and then characterized by elemental analysis,IR spectroscopy,thermogravimetric analysis(TGA),powder X-ray diffraction(PXRD)and single-crystal X-ray diffraction.The single-crystal X-ray diffraction reveals that two complexes feature carboxylato-bridged binuclear subunits extended further by the nitrogen-rich coligands to form different structures.Complex 1 containing phda-bridged binuclear cobalt is developed by itmb coligand to 1D double-stranded chain,whereas complex 2 exhibits 2D open bilayers,which result from the ribbon-like carboxylate chains pillared Hpytz coligands.In addition,the magnetic susceptibilities of both compounds were measured over the temperature range of 3~300 K,and the data were analyzed well using Mag Saki software.The best fitting parameters wereκ=0.98,λ=-100 cm-1,?=588 cm-1 and J=0.6 cm-1 for complex 1 andκ=0.86,λ=-110 cm-1,?=756.8 cm-1 and J=-1.25 cm-1 for complex 2.The results indicate the existence of weaker ferromagnetic interaction for complex 1 and antiferromagnetic interaction for complex 2 between the metal centers in the dinuclear metal units.

Analytical Application of Ion Associates of Molybdenum with Dithiolphenols and Aminophenols

The mixed-ligand complexes of molybdenum(VI) with dithiolphenols (DP) {2,6-dithiol-4-methylphenol (DTMP), 2,6-dithiol-4-ethylphenol (DTEP) and 2,6-dithiol-4-tert-butylphenol (DTBP)} in the presence of hydrophobic amines have been investigated by spectrophotometric method. The condition of complexing and extraction, physical-chemical and analytical characteristics of this complex have been found. As hydrophobic amine 2(N, N-dimethylaminomethyl)-4-methylrphenol (АP1) and 2(N, N-dimethylaminomethyl)-4-xlor-phenol (AP2), 2 (N, N-dimethylamino-methyl)-4-brom-phenol (AP3) were used. It has been found that mixed-ligand complex was formed in weakly acidic medium (pH 4.1 - 5.9). The maximum analytical signal when complexing Mo(V) is observed at 516 - 534 nm. The calculated molar absorption (εmax) belongs to the range (4.16 - 5.35) × 104. The Beer’s law was applicable in the range of 0.3 - 22 μg/ml. The extraction photometric methods of the molybdenum determination were processed. The influence of diverse ions on determination of molybdenum has been studied. The proposed method was applied successfully to determine amount of molybdenum in steel and in soil.