硝酸铽与1,1,1'''',1''''-四(吡啶-2-羧酸酯基)联三甲基丙烷配合物的合成、表征及荧光性质

稀土离子具有独特的电子结构和成键特征,配位数高且多变,因而稀土配合物能表现出独特的光、电、磁性质。目前,设计和合成含有稀土离子的功能配合物作为发光分子器件和荧光探针是配位化学和超分子化学等研究领域的热点课题[1￣6]。研究表明,稀土配合物的发光性能和稳定性可通过改变其配体的组成和结构加以调控。因此,设计、合成具有新颖结构、良好配位能力及高效能量吸收和传递性能的有机配体是研究和开发新型稀土配合物发光材料的关键课题之一。多足配体在与金属离子配位时,能够表现出特有的选择性配位能力、类球形配位空穴和新颖的配位结构…     

对三氟甲基苯甲酸和2，2’-联吡啶双核铽配合物的合成、晶体结构及发光性质

羧酸可以采取螯合双齿,桥式双齿,μ3-桥式和单齿等多种形式与稀土离子配位,相应的配合物往往具有层状、无限链状和网层状聚合等特殊结构。羧酸稀土配合物在发光材料、催化和磁性材料等方面均有应用因而受到广泛关注[1-5]。其中芳香羧酸与稀土离子的配合物由于具有优异的发光性能和热稳定性一直是人们研究的热点[6-10]。文献[6-9]对稀土．     

N-对甲苯磺酰-5-氨基间苯二甲酸构筑的一维配位聚合物的合成、晶体结构和荧光性质

采用普通溶液法和水热法分别合成了2个金属-有机配位聚合物:{[Cu(Ts-5-AIPA)(phen)(H_2O)]·H_2O}n(1)和[Cd(Ts-5-AIPA)(phen)]n(2)(Ts-5-AIPA=N-对甲苯磺酰-5-氨基间苯二甲酸根,phen=菲咯啉),并用红外光谱、热重和X射线单晶衍射对配合物的结构进行了表征。结果表明:2个配合物均为单斜晶系,配合物1为P21/c空间群,配合物2为C2/c空间群;2个配合物均为一维链状结构,再通过氢键和π-π堆积作用形成三维超分子结构。另外,还研究了2个配位聚合物的荧光性质。     

双β-二酮配体配位性的理论研究

基于自洽反应场(SCRF)中的极化连续介质模型(PCM), 采用密度泛函理论B3LYP/6-31G**计算了以二硫醚和芳环为桥基的两类双β-二酮配体的空间构型和电子结构, 结合其配合物晶体结构数据, 研究配体分子电子结构与配位性的关联性. 结果表明, 配体分子的几何构型、前线轨道、偶极矩和电荷布居, 与配合物构型、活性配位原子和配位形式(单核或多核、分子内或分子间)之间的关联性与一致性十分有意义. 配体的理论计算研究可以在一定层次上为配合物几何结构特征和配位特性提供合理的分析与预测.     

基于D(-)/L(+)-对羟基苯甘氨酸配体的两个铜配合物的合成、结构和电化学性质

利用手性配体D(-)/L(+)-对羟基苯甘氨酸(D/L-Hhpg)与铜盐在溶液法条件下合成2个手性配合物{[Cu(D-hpg)(phen)(NO_3)]·1.5H_2O}_n(1)和{[Cu(L-hpg)(phen)(NO_3)]·2H_2O}_n(2),(phen=1,10-菲咯啉)。对2个配合物进行了元素分析、红外光谱、粉末X射线衍射、单晶X射线衍射、固态圆二色谱表征及热重-差热分析。配合物1和2是正交晶系,P2_12_12_1手性空间群,二者均为1D链状结构并通过氢键作用形成3D超分子结构。有趣的是,配合物1和2中的配位硝酸根与晶格水分子之间的氢键作用使它们分别生成了沿b轴方向的左手和右手超分子螺旋链。此外,基于配合物1和2的中心金属离子为Cu(Ⅱ),进一步探究了电化学性能。循环伏安结果表明生成的配合物具有电化学活性,在扫描速率为0.025～1.0 V·s~(-1)范围内,配合物制备的碳糊电极上的电化学过程是由表面控制的。     

铜(Ⅱ)-N-(2-羟苄基)-DL-α-苯丙氨酸-2，2′-联吡啶(或1，10-邻菲咯啉)三元配合物的合成、晶体结构及抑菌活性

合成了铜(Ⅱ)与N-(2-羟苄基)-DL-α-苯丙氨酸(H₂sphe)和2，2′-联吡啶(2，2′-bipy)及1，10-邻菲咯啉(phen)的三元配合物 [Cu(Hsphe)(phen)](ClO₄)·3H₂O (1)、[Cu(Hsphe)(2，2′-bipy)](ClO₄) (2)、[Cu(Hsphe)(2，2′-bipy)](NO₃) (3)。用X射线单晶衍射测定了配合物的晶体结构。3种配合物中Cu(Ⅱ)离子配位数均为5，处于变形四方锥配位环境中。抑菌活性试验结果表明，3种配合物均对金黄色葡萄球菌、铜绿假单胞菌和枯草杆菌有一定的抑制作用。配合物1还对大肠杆菌、伤寒杆菌有较强的抑制作用，而配合物3对伤寒杆菌亦有一定的抑制作用。     

柔性双咪唑配体环状金（Ⅰ）配合物的合成、表征及荧光性质

采用扩散法制备了2个基于柔性双咪唑配体的Au(Ⅰ)配合物,[Au_2(m-bitmb)_2][AuCl_2]Cl·2CH_3OH (1)和[Au_2(m-bitmb)_2][AuCl_2]_2·2CH_3CN (2)(m-bitmb=1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene),并使用X射线单晶衍射、元素分析、XRD等测试手段进行了表征,研究了配合物的荧光性质。结构分析结果表明配合物1和2均具有M_2L_2的环状结构单元,其结构中双齿配体mbitmb均采用顺式构型参与配位,M_2L_2结构单元通过π-π堆积相互作用排列而形成一维链状结构。配合物1和2具有更强的π-π堆积作用,但亲金性稍弱。通过对比2种配合物和配体的荧光发射,发现配合物中存在的亲金相互作用对其荧光性质具有很重要的影响和作用。     

NH_4[RE(Ac)_4·H_2O]发光稀土配合物的研究

以乙酸和乙酸铵为配体,合成了新颖发光稀土配合物,通过元素分析、红外光谱、热重分析等手段对配合物进行了表征,确定其结构为NH4[RE(Ac)4.H2O](RE=Tb或Eu).结果表明,配合物中羧基以螯合、双齿和单齿方式与稀土离子配位;并通过荧光光谱分析、荧光寿命研究了其发光性能,配合物能发射强的稀土离子的特征荧光且有较长的荧光寿命.     

铜离子(II)与Ab多肽形成可溶性配合物结构的理论研究

大脑中淀粉样Cross-β纤维沉淀是老年痴呆症(AD)的一个关键性病理特征. X射线分析显示有大量Cu^2＋和Zn^2＋集中到患者的大脑中, 暗示了这些失调的离子与AD疾病有关. 实验发现, 在适度酸性pH值下, Cu^2＋与组氨酸咪唑环上的Nt配位可诱导Ab多肽聚合成沉淀, 而在中性pH值下, Cu^2＋与组氨酸咪唑环上的Np及主链上的去质子N或O配位生成可溶的配位化合物. 本文应用密度泛函理论(B3LYP)方法, 研究了Cu^2＋与Ab多肽中的四肽(HHQK)形成可溶性配合物的结构, 结果得到N(3)O(1)及N(4)O(1)两类配位方式, 其中以N(3)O(1)配位形成变形的平面正方形配位结构, 而以N(4)O(1)配位形成变形的四方锥结构. 由于分子内氢键的形成, 优化得到了6个不同的结构, 通过能量对比找到了最稳定的结构, 并深入探讨了最稳定结构的原子电荷布居规律、一些前沿分子轨道以及配合物的振动光谱, 在振动光谱方面, 理论与实验符合得很好.     

咪唑-菲咯啉-苯氧乙酸锌、铅配合物的合成,结构及与DNA的相互作用

以2-4-(1H-咪唑-2-[4,5-f][1,10]菲咯啉基)苯氧乙酸(HPIMPHC)和2-2-(1H-咪唑-2-[4,5-f][1,10]菲咯啉基)苯氧乙酸(HOIMPHC)为配体,水热合成了2种新型配合物[Zn(PIMPHC)₂]_n(1)和{[Pb(OIMPHC)₂]·4H₂O}_n(2)。配合物1属正交晶系,空间群为Pbcn;Zn(Ⅱ)的配位数为6,配位构型为变形的八面体,形成2D网状结构。配合物2属单斜晶系,空间群为P2₁/n;Pb(Ⅱ)的配位数为7,配位构型为变形的五角双锥,形成2D网状结构。荧光光谱的结果表明,配合物与DNA的相互作用强于配体。     

Asymmetrische Hg(II)-Komplexe mit Organothiolato- bzw. Organoselenolato-und Triazenato-Liganden

The mixed mercury complexes (2XC₆H₄)₂N₃HgY (X=CH₃, F, Cl, Br, I;Y=SC₂H₅, SC₆H₅, SeC₆H₅) have been prepared. Both the Hg–S and Hg–Se bonds and, in contrast to other mixed triazenato-mercury compounds, the triazenato-mercury bonds have been shown to be kinetically labile on the NMR time scale by means of⁷⁷Se and¹⁹⁹Hg NMR spectroscopy. Evidence has been obtained for the presence of (2XC₆H₄)₂N₃HgY together with HgY ₂ and [(2XC₆H₄)₂N₃]₂Hg in solution.

     

Thermal Behaviour of the N-donor Adducts of Metal Saccharinates. II. 1,10-phenanthroline saccharinato complexes of Co(II), Ni(II), Cu(II), Zn(II) and Pb(II)

Adducts of Co(II), Ni(II), Cu(II), Zn(II) and Pb(II) saccharinates with 1,10-phenathroline were synthesized and their thermoanalytical (TG, DTG and DTA) curves in the 20–1000°C temperature interval and static air atmosphere were recorded. The complexes are best represented as M(C₁₂H₈N₂)_x(C₇H₄NO₃S)₂⋅yH₂O (x=2, 2, 2, 2 and 1; y=1, 1, 2, 1 and 2 for M=Co, Ni, Cu, Zn and Pb, respectively). The decomposition of the compounds regularly started with dehydration, followed by loss of the phenanthroline ligand(s). The structures of the Cu and Pb complexes are notably different from other compounds. FTIR spectra of the title compounds in the region of the OH, CO and SO₂ stretching vibrations were also studied. The pronounced similarity of the spectra of Co, Ni and Zn adducts indicates possible isomorphism among them. This revised version was published online in July 2006 with corrections to the Cover Date.     

N-(2-吡咯甲基)-1-苯基乙亚胺·二甲基铝的合成、结构及其催化丙交酯的活性

通过席夫碱配体N-（2-吡咯甲基）-1-苯基乙亚胺与三乙基铝按物质的量之比为1：1在无氧无水的条件下反应,合成了席夫碱铝的有机金属化合物N-（2-吡咯甲基）-1-苯基乙亚胺·二甲基铝。其结构分别用核磁氢谱、碳谱,元素分析和X射线单晶衍射技术进行了表征。铝化合物在催化外消旋丙交酯开环聚合反应中表现出了中等的活性并得到了以等规聚合为主的高聚物。     

N-(2-吡咯甲基)-1-苯基乙亚胺·二甲基铝的合成、结构及其催化丙交酯的活性

通过席夫碱配体N-（2-吡咯甲基）-1-苯基乙亚胺与三乙基铝按物质的量之比为1：1在无氧无水的条件下反应,合成了席夫碱铝的有机金属化合物N-（2-吡咯甲基）-1-苯基乙亚胺·二甲基铝。其结构分别用核磁氢谱、碳谱,元素分析和X射线单晶衍射技术进行了表征。铝化合物在催化外消旋丙交酯开环聚合反应中表现出了中等的活性并得到了以等规聚合为主的高聚物。     

The thermal dehydration and decomposition of Ba[Cu(C2O4)2(H2O)]·5H2O

The thermal behaviour of Ba[Cu(C₂O₄)₂(H₂O)]·5H₂O in N₂ and in O₂ has been examined using thermogravimetry (TG) and differential scanning calorimetry (DSC). The dehydration starts at relatively low temperatures (about 80°C), but continues until the onset of the decomposition (about 280°C). The decomposition takes place in two major stages (onsets 280 and 390°C). The mass of the intermediate after the first stage corresponded to the formation of barium oxalate and copper metal and, after the second stage, to the formation of barium carbonate and copper metal. The enthalpy for the dehydration was found to be 311±30 kJ mol^–1 (or 52±5 kJ (mol of H₂O)^–1). The overall enthalpy change for the decomposition of Ba[Cu(C₂O₄)₂] in N₂ was estimated from the combined area of the peaks of the DSC curve as –347 kJ mol^–1. The kinetics of the thermal dehydration and decomposition were studied using isothermal TG. The dehydration was strongly deceleratory and the -time curves could be described by the three dimensional diffusion (D3) model. The values of the activation energy and the pre-exponential factor for the dehydration were 125±4 kJ mol^–1 and (1.38±0.08)×10¹⁵ min^–1, respectively. The decomposition was complex, consisting of at least two concurrent processes. The decomposition was analysed in terms of two overlapping deceleratory processes. One process was fast and could be described by the contracting-geometry model withn=5. The other process was slow and could also be described by the contracting-geometry model, but withn=2.The values ofE _a andA were 206±23 kJ mol^–1 and (2.2±0.5)×10¹⁹ min^–1, respectively, for the fast process, and 259±37 kJ mol^–1 and (6.3±1.8)×10²³ min^–1, respectively, for the slow process.Dedicated to Prof. Menachem Steinberg on the occasion of his 65th birthday     

Hydrazinium Oxalatometallates of Rare Earths(III)

Oxalates of La(III), Ce(III), Pr(III), Nd(III) and Sm(III) with the hydrazinium cation with the general formulae (N₂H₅)₄Ln₂(C₂O₄)₅7H₂O (Ln=La³⁺, Ce³⁺, Pr³⁺) and N₂H₅Ln(C₂O₄)₂·3.5H₂O (Ln=Nd³⁺, Sm³⁺) were synthesized. The thermal decompositions of these compounds take place in three stages: thermal dehydration at 65–100°C, exothermic decomposition of the N₂H₄ at 230–260°C, and oxidation of the oxalate ion.This revised version was published online in November 2005 with corrections to the Cover Date.     

Synthesis,Antiproliferative Activity and DNA-Binding Properties of Nitrogen and Sulfur Heterocyclic Norcantharidin Acylamide Acid

Three novel norcantharidin acylamide acids (L¹?N‐thiadiazole norcantharidin acylamide acid, C₁₀H₁₁N₃O₄S; L²?N‐thiazole norcantharidin acylamide acid, C₁₁H₁₂N₂O₄S and L³?N‐benzothiazole norcantharidin acylamide acid, C₁₅H₁₄N₂O₄S) were synthesized by the reactions of norcantharidin (NCTD?7‐oxabicyclo[2,2,1]heptane‐2,3‐dicarboxylic acid anhydride, C₈H₈O₄) with 2‐amino‐1,3,4‐thiadiazole (C₂H₃N₃S), 2‐aminothiazole (C₃H₄N₂S) and 2‐aminobenzothiazole (C₇H₆N₂S), respectively. Their structures were characterized by elemental analysis, IR, and NMR. The inhibition rates of L³ was much higher than those of L¹ and L² against human hepatoma cells SMMC7721 cell lines in vitro. The interaction between the compounds and DNA was studied by means of fluorescence quenching studies and viscosity measurements. The emission intensities decreased obviously with increasing concentration of the compounds in the fluorescence quenching experiments. The linear Stern‐Volmer quenching constant K_sq values were 0.62 (L¹), 0.55 (L²) and 1.08 (L³), respectively. The binding abilities followed the trend from high to low were L³, L¹ and L², respectively. The results of viscosity measurements showed that L¹ and L² might bind to DNA via partial intercalation, while L³ bound mainly in intercalation.     

Preparation and thermal behaviour of rare earth citrate hydrates

Nine rare earth citrate hydrates (RE(C₆H₅O₇)·nH₂O,RE=La, Nd, Sm) were prepared and characterized by chemical analysis, elementary analysis, thermal analysis and IR spectra. The thermal decomposition processes were studied by using TG-DTG and IR spectra techniques. Dehydration enthalpies and dehydration entropies of 3 neodymium and 3 samarium citrate hydrates were also determined by means of DSC.     

α-乙酰氧基-N-亚硝基吡咯烷的解离及其致癌代谢机理的理论研究

用ab initio方法, 在MP2/6-31G**水平下讨论了α-乙酰氧基-亚硝基吡咯烷(α-Acetoxy-NPYR)在各种条件下的解离反应机理, 并对形成终致癌物B, C, D的代谢机理进行研究. 发现在OH^－和H₂O作用下的解离都遵循羟基进攻羰基机理, OH^－作用下是一个经四面体中间体阴离子的无位垒过程, H₂O作用下有相对高的活化能(165.36 kJ/mol). H₃O^＋作用下是先形成阳离子产物的S_N1过程, 并没有发现遵循两种综合的解离情形. 同时, 羟基化产物异构化为终致癌物B, C, D是一个相对容易进行的过程.     

Ringsubstituierte [1]titanocenophane

The ring-substituted bis(cyclopentadienyl)silanesMe ₂Si(C₅H₅) (MeC₅H₄) (1a) andMe ₂Si(MeC₅H₄)₂ (2a) could be prepared by the reactions ofMe ₂SiCl₂ with C₅H₅Na andMeC₅H₄Na or only withMeC₅H₄Na, respectively. Metallation of1 a or2 a withn-BuLi and following reaction with TiCl₄ led to the first ringsubstituted [1]titanocenophanes,Me ₂Si(C₅H₄) (MeC₅H₃)TiCl₂ (1 b) orMe ₂Si(MeC₅H₃)₂ TiCl₂ (2 b), respectively. On reaction with NaI,1 b yieldedMe ₂Si(C₅H₄) (MeC₅H₃)TiI₂ (1 c). Structural assignments of the compounds could be made on the basis of their¹H NMR spectra.