含茂、非茂混合配体钛族络合物的合成与催化烯烃聚合的研究进展

目前金属有机钛族络合物的发展呈现出多元化的趋势:茂络合物、非茂络合物以及茂非茂混合配体络合物,而其中茂、非茂混合配体络合物是近年来发展的一个新亮点.关于茂钛族络合物、非茂钛族络合物近年已经有过许多的综述,而关于茂、非茂混合配体钛族络合物的综述却很少.综述了近年来茂、非茂混合配体钛族络合物合成与催化烯烃聚合的研究进展.     

四环素-铜(Ⅱ)配合物与DNA相互作用的吸收光谱研究

用紫外光谱方法研究了四环素(TC) Cu(II)配合物与DNA的相互作用.吸收光谱研究表明,DNA能与四环素(TC)及Cu(II)形成的配合物发生反应,配合物与DNA的作用方式随着配合物类型及DNA浓度的不同而不尽相同:当四环素与铜形成1∶1型配合物时,较低浓度的DNA能与配合物以嵌插方式相互作用,而较高浓度的DNA与该配合物除了发生嵌插作用外,还存在另外的作用方式;当四环素与铜形成1∶2型配合物时,DNA与该配合物则主要以嵌插方式相互作用,并且这两种配合物与DNA的嵌插作用均是通过四环素配体插入的.     

Cycling between Molybdenum-Dinitrogen and -Nitride Complexes to Support the Reaction Pathway for Catalytic Formation of Ammonia from Dinitrogen

Cycling between molybdenum(I)-dinitrogen and molybdenum(IV)-nitride complexes was investigated under ambient reaction conditions. A kinetic study of the second-order reaction rate for the conversion of the molybdenum-dinitrogen complex into the molybdenum-nitride complex indicates that the formation of the dinitrogen-bridged dimolybdenum complex is involved in the rate-determining step. DFT calculations indicate that the molybdenum-dinitrogen complex transforms into the molybdenum-nitride complex via direct cleavage of the nitrogen-nitrogen triple bond of the bridging dinitrogen ligand of the dinitrogen-bridged dimolybdenum complex. The corresponding reaction of the molybdenum-nitride complex transforming into the molybdenum-dinitrogen complex proceeds via the ligand exchange of ammonia for dinitrogen at the dinitrogen-bridged dimolybdenum complexes. A new modified reaction pathway has been proposed based on the findings of our experimental and theoretical results.     

Gelled Complex Fluids: Combining Unique Structures with Mechanical Stability

Gelled complex fluids are soft materials in which the microstructure of the complex fluid is combined with the mechanical stability of a gel. To obtain a gelled complex fluid one either adds a gelator to a complex fluid or replaces the solvent in a gel by a complex fluid. The most prominent example of a “natural” gelled complex fluid is the cell. There are various strategies by which one can form a gelled complex fluid; one such strategy is orthogonal self‐assembly, that is, the independent but simultaneous formation of two coexisting self‐assembled structures within one system. The aim of this Review is to describe the structure and potential applications of various man‐made gelled complex fluids and to clarify whether or not the respective system is formed by orthogonal self‐assembly.     

铽-聚二甲基硅氧烷配合物的荧光特性

用多种谱学方法证明聚二甲基硅氧烷(PDMS)中的氧原子能与Tb3+键合生成Tb3+和PDMS的配合物(Tb3+-PDMS), 并发现生成配合物后, PDMS和Tb3+的荧光发射同时得到增强. 荧光强度的增强与配合物中Tb3+含量有关, 当配合物中Tb3+的含量为2.0%(w)时, 配合物的荧光强度最大, 可增强1547%左右.     

Dynamics in a pure encounter complex of two proteins studied by solution scattering and paramagnetic NMR spectroscopy

In the general view of protein-complex formation, a transient and dynamic encounter complex proceeds to form a more stable, well-defined, and active form. In weak protein complexes, however, the encounter state can represent a significant population of the complex. The redox proteins adrenodoxin (Adx) and cytochrome c (C c) associate to form such a weak and short-lived complex, which is nevertheless active in electron transfer. To study the conformational freedom within the protein complex, the native complex has been compared to a cross-linked counterpart by using solution scattering and NMR spectroscopy. Oligomerization behavior of the native complex in solution revealed by small-angle X-ray scattering indicates a stochastic nature of complex formation. For the cross-linked complex, interprotein paramagnetic effects are observed, whereas for the native complex, extensive averaging occurs, consistent with multiple orientations of the proteins within the complex. Simulations show that C c samples about half of the surface area of adrenodoxin. It is concluded that the complex of Adx/C c is entirely dynamic and can be considered as a pure encounter complex.     

Syntheses, Structures, and Blue Luminescent Properties of 2,6-Bis（benzimidazolyl） Pyridine and Its Mercury Complex

IntroductionLuminescent metal complexes have attracted in-creasing attention because of their potential applicationin the areas of chemistry, medicine, and material sci-ences[1—4]. Several luminescent complexes of the maingroups and the transition metals…     

Preparation and Characterization of Clopidogrel/DIMEB Complex

Surprisingly, it was found that Clopidogrel base (CLP) easily forms a solid complex with DIMEB in cold solution by precipitation. The complex can be isolated by filtration, the stoichiometry of the isolated complex corresponds to 1 : 1 molar ratio. Powder X-ray diffractometry proved the complex formation in solid state. The improved solubility of the complex offers the possibility of an adequate drug release over the whole pH-range of the GI-tract.     

3,5-二碘水杨醛缩邻苯二胺Ni(Ⅱ)配合物的合成及生物活性

合成了3,5-二碘水杨醛缩邻苯二胺席夫碱合镍(Ⅱ)配合物。 通过核磁共振、元素分析、紫外光谱、红外光谱及摩尔电导对结构进行了表征,用Gaussian03程序优化计算,确定配合物的结构为Ni(Ⅱ)L。 通过紫外光谱、粘度法及与溴化乙锭(EB)的竞争实验,研究了配合物与小牛胸腺DNA(ct-DNA)的作用情况。 结果显示,配合物与DNA作用时,紫外吸收发生明显的减色效应,其结合常数为Kb=1.129×105 L/mol;EB-DNA体系的荧光强度随配合物的加入迅速减弱;配合物的加入使ct-DNA的粘度增加。 这些结果表明,该化合物以插入式与ct-DNA键合。 并用打孔法测试了配合物对藤黄微球菌(M.luteus)的抑制作用。     

Synthesis,structure, and biological properties of a Co(II) complex with tridentate Schiff base ligand

A new Co(II) complex of general formula [Co(L)₂] has been synthesized from a NNO tridentate Schiff base ligand, 2-[(piperidin-2-ylmethylimino)-methyl]-phenol (L). The title complex is characterized by elemental, spectroscopic, antibacterial, and single crystal X-ray structural studies. X-Ray crystallography reveals that the complex shows a distorted octahedral geometry around the Co(II) ion. The complex was tested against several bacteria and shows good antibacterial activities against almost all of the bacteria. The interactions of the title complex with calf thymus deoxyribonucleic acid (CT-DNA) have been investigated by electronic absorption and fluorescence spectroscopy, showing that the complex interacts with CT-DNA via partial intercalation. Thermogravimetric analysis (TGA) of the complex has also been reported and the result shows that the complex is thermally stable up to 134 °C.     

聚乙烯亚胺-钴络合物对氧还原电流的影响

研究了聚乙烯亚胺 钴络合物 (PEI Co)在电解质溶液中的氧可逆结合特性及对氧还原电流的影响 .PEI Co络合物溶解于电解质的水溶液中 ,在氧气气氛中络合物与氧结合 ,UV Vis光谱在 310nm处出现了新的吸收峰 ,并在 2 80nm处观察到等吸光点 .PEI Co络合物与氧结合平衡曲线服从Langmuir行为 ,络合物与氧结合的亲和力 (p50 )为 0 6 6 7kPa .氧与PEI Co加成物的解离反应表观速率常数为 1 1× 10 5s- 1 ,表明络合物具有快速、可逆的氧结合特性 .在PEI Co络合物存在下 ,氧电极的还原电流显著增加 ,并且随PEI Co络合物的浓度以及气氛中氧浓度的增加而增加 .[PEI链节 ] [Co]=5 1时 ,氧还原电流达到极大值 ,说明PEI Co络合物与氧形成了结构为 [N5CoⅢ O2 CoⅢ N5]的加成物 .     

硫脲壳聚糖Co(Ⅱ)配合物的制备、抑茵活性及与血清白蛋白的作用

合成了硫脲壳聚糖Co(Ⅱ)配合物,运用红外光谱、紫外光谱和差热热重分析对配合物进行了表征,研究了其对大肠杆菌和金黄色葡萄球菌的抑菌性能及与血清白蛋白(BSA)的相互作用.结果表明,硫脲壳聚糖能与Co(Ⅱ)发生配位反应而生成硫脲壳聚糖-Co(Ⅱ)配合物,该配合物的抑菌性能较壳聚糖和硫脲壳聚 糖有显著提高,并能有规律地猝灭...     

Evaluation of 99mTc-HIDA complex as a cholescintigraphic agent (author's transl)

In the reaction labeling N-(2,6-dimethylphenylcarbamoylmethyl) iminodiacetic acid (HIDA) with 99mTc, several complexes with different chemical characteristics were observed to occur with slight changes in the labeling conditions. Among these complexes, a complex detected in the bile of rats was limited to one complex, named as complex II. The preparation method of 99mTc-HIDA complex II and the exchange reaction between this complex and penicillamine indicate that 99mTc is coordinated with HIDA as low-hydrolyzed 99mTc in this complex. This complex is excreted rapidly through the bile and within 1 hr, about 65% of the total activity injected is recovered from bile in rats. The organ distribution of this complex was studied in mice by radioassay and in rabbits by scintillation camera and, in both cases, the radioactivity was accumulated in the gallbladder. These results suggest that the 99mTc chemical state, low-hydrolyzed state, relates to the bile excretion behavior of this complex, a potentially useful cholescintigraphic agent.     

阿霉素─铁(Ⅲ)配合物的电化学特征及其与DNA结合作用研究

采用示波极谱法和循环伏安法研究了3公铁离子Fe(Ⅲ)与阿霉素(ADM)配合物的电化学特性.在生理pH条件下,Fe(Ⅲ)与ADM形成2：1的稳定配合物,Fe(Ⅲ)的配位使ADM在更负的电势下才能还原,这与其心脏毒性减轻密切相关.采用线性扫描、吸收光谱和凝胶电泳法研究了ADM－Fe(Ⅲ)配合物与DNA的结合作用,ADM－Fe(Ⅲ)配合物仍保留了ADM插入结合的特征,并形成一种稳定的DNA－Fe(Ⅲ)－ADM的三元结合物.     

壳聚糖维生素C复合物的合成及性能

通过离子间静电引力作用合成了壳聚糖维生素C复合物。采用红外光谱和差热分析测试技术表征了复合物的结构。溶解度测定结果表明,该复合物具有水溶性。邻苯三酚自氧化速率测定结果表明,该复合物对.O2-的清除作用优于壳聚糖。     

纳米Pb(II)-没食子酸配合物的合成及其燃烧催化性能

采用液相分散沉淀法制备了纳米 Pb(II)-没食子酸配合物粉体. 用热重分析(TG)、X 射线衍射仪(XRD)、透射电镜(TEM)、核磁共振仪(1H NMR)、红外光谱仪(IR)、激光散射粒径分析仪和元素分析仪对样品的物相、形貌、粒径和组成进行了表征. 研究了没食子酸的浓度和分散剂用量对产物的粒子大小的影响. 并测试了产物对推进剂燃烧的催化作用. 结果表明: 产物的平均粒径约为 30 nm. 没食子酸的浓度降低和分散剂用量增加均使产物的粒子减小. 产物能明显改善推进剂的燃烧性能, 使推进剂的燃速提高 88%, 压强指数降低了 70%.     

A Chiral Macrocyclic Tetra-N-Heterocyclic Carbene Yields an “All Carbene” Iron Alkylidene Complex

The first chiral macrocyclic tetra-N-heterocyclic carbene (NHC) ligand has been synthesized. The macrocycle, prepared in high yield and large scale, was ligated onto palladium and iron to give divalent C₂-symmetric square planar complexes. Multinuclear NMR and single crystal X-ray diffraction demonstrated that there are two distinct NHCs on each ligand, due to the bridging chiral cyclohexane. Oxidation of the iron(II) complex with trimethylamine N-oxide yielded a bridging oxo complex. Diazodiphenylmethane reacted with the iron(II) complex at room temperature to give a paramagnetic diazoalkane complex; the same reaction yielded the “all carbene” complex at elevated temperature. Electrochemical measurements support the assignment of the “all carbene” complex being an alkylidene. Notably, the diazoalkane complex can be directly transformed into the alkylidene complex, which had not been previously demonstrated on iron. Finally, a test catalytic reaction with a diazoalkane on the iron(II) complex does not yield the expected cyclopropane, but actually the azine compound.     

An infrared spectroscopic study of the formaldehyde complexes of dimethyl ether and methanol in solid nitrogen

IR spectra of the formaldehyde complexes of methanol and dimethyl ether in solid nitrogen at 20 K are reported. Dimethyl ether forms a non hydrogen bonded complex, analogous to a previously studied dimethyl sulfide-formaldehyde complex. Methanol forms a hydrogen bonded complex with formaldehyde and in addition appears to form another complex probably with a structure similar to that of the dimethyl ether-formaldehyde complex.     

Conversion of oxido-bridged dinuclear ruthenium complex to dicationic dinitrosyl ruthenium complex using proton and nitric oxide: completion of NO reduction cycle

The hydroxido-bridged dinuclear ruthenium complex 4, which is supported by Tp ligands, has been prepared from protonation of the oxido-bridged dinuclear ruthenium complex 3. Additional protonation of 4, affording the aqua-bridged dinuclear ruthenium complex 5 in situ, and subsequent treatment with NO gave rise to the dicationic dinitrosyl complex 2. These indicate completion of the NO reduction cycle on the dinuclear ruthenium complex.     

Structural characterization of disperse black 9 based Cu (II) complex and investigation of its some properties

We obtained the azo‐imine ligand (2,2′‐[4‐(5‐methoxy salicylidene‐4‐iminophenylazo)phenylimino]diethanol) (HL) and its Cu (II) complex (CuL) from the ethanol solution. The complex Cu(L)₂ was obtained as single crystals from the CH₃OH solution and structurally characterized. The electronic and photoluminescence properties of the ligand and its Cu (II) complex were investigated both in DMF solution and solid state. The oxidation and reduction behaviours of the compounds were studied in the solution and found that the redox processes are irreversible. Thermal studies show that the ligand has higher thermal stability than the CuL complex. Single crystals of the complex were obtained from slow evaporation of a DMF solution of the complex. Crystals of the complex showed a diffraction pattern; however, the structure of the complex was able to be solved.