三种马来二腈基二硫烯镍(Ⅲ)离子对配合物的制备和结构表征

合成了3种离子对配合物 [1-benzyl-3-bromopyridium]⁺[Ni(mnt)₂]^- (1)，[1-(4′-flurobenzyl)-3-bromopyridiunm]⁺[Ni(mnt)₂]^- (2)，[1-(4′-cholorobenzyl)-3-bromopyridium]⁺[Ni(mnt)₂]^- (3)，(mnt=马来二腈基二硫烯，maleonitrile dithiolate)获得了单晶并解析了它们的单晶结构。     

Ru(Ⅱ)和Ru(Ⅲ)配合物[Ru(bpy)(PH3)(-C≡CC6H4NO2-p)Cl]m(m=0，+1)的光谱性质的密度泛函-含时密度泛函理论研究

我们利用DFT中的B3LYP方法优化了Ru(Ⅱ)配合物和氧化的Ru(Ⅲ)配合物[Ru(bpy)(PH₃)(-C≡CC₆H₄NO₂-p)Cl]^m[bpy=2，2′-bipyridine;m=0 (1)，+1 (1⁺)]的基态几何结构，得到的几何参数与实验结果吻合的很好。采用TDDFT方法，得到了配合物1和1⁺的激发态电子结构和电子吸收光谱。研究结果表明，配合物1和1⁺随着氧化过程的发生，光谱性质也发生变化，Ru(Ⅱ)配合物的低能吸收被指认为MLCT/LLCT混合跃迁，而氧化的Ru(Ⅲ)配合物1⁺的低能吸收具有LMCT跃迁性质。     

O—P—O桥联锰-席夫碱配合物的合成、结构和磁性质

采用溶液法合成了2例由O—P—O单元桥联的锰-席夫碱(SB)新型三核配合物,即[Mn₃(salen)₃(L)]ClO₄·H₂O (1)和[Mn₃(salpn)₃(L)]ClO₄(2),其中salen^2-=N,N''-乙二胺缩双水杨醛,salpn^2-=N,N''-丙二胺缩双水杨醛,H₂L=(5-(乙氧基羰基)萘-1-基)膦酸。通过单晶X射线衍射、红外光谱、粉末X射线衍射对其进行了表征。配合物1和2是同构的,均是由膦酸酯配体中的O—P—O桥联3个[Mn (SB)]+构成一个三核结构单元[Mn3(SB)3(L)]⁺,一个无序的ClO₄^-作为平衡阴离子存在。这些[Mn₃(SB)₃(L)]⁺三聚体通过π-π相互作用和相邻的分子形成超分子一维波形链。配合物1和2的磁性研究表明,不对称结构中的3个Mn(Ⅲ)离子分别是2个高自旋和1个低自旋,而Mn(Ⅲ)离子之间主要存在反铁磁相互作用。     

镍(Ⅱ)和铜(Ⅱ)Schiff碱配合物的合成及其晶体结构

合成了2个Schiff碱配体:双(溴代乙酰丙酮)缩乙二胺[表示为H₂(3-Br-acacen)]和二(溴代乙酰丙酮)缩-1，2丙二胺[表示为H₂(3-Br-acacpen)]，Schiff碱配体与醋酸镍或醋酸铜作用分别得到相应的4个Schiff 碱金属配合物:Ni^Ⅱ(3-Br-acacen) (1)、Cu^Ⅱ(3-Br-acacen) (2)、Ni^Ⅱ(3-Br-acacpen) (3)和Cu^Ⅱ(3-Br-acacpen) (4)。用FTIR和元素分析对配合物进行表征，并用X-射线单晶衍射测定了4个配合物的晶体结构。配合物1 和2 的分子基本为一平面结构，3和4则是非平面分子结构。     

含樟脑衍生物氰基桥联双金属配合物的合成、结构及磁性质

采用樟脑衍生物为配体，分别合成了氰基桥联Cu(Ⅱ)-Fe(Ⅲ)-Cu(Ⅱ)三核配合物[{Cu(D,L-La)₂}₂Fe(CN)₆](ClO₄) (1)和Mn(Ⅲ)-Fe(Ⅲ)双核配合物[Mn(D,L-Lb)(DMF)(Tp)Fe(CN)₃]·(H₂O)₆ (2)。晶体结构分析表明，化合物1中Cu(Ⅱ)离子处于五配位的配位环境，分别和1个D-La，1个L-La及[Fe(CN)₆]^3-中的1个氰基配位，2个Cu(Ⅱ)离子通过[Fe(CN)₆]^3-桥联。通过分子间氢键作用，化合物1形成二维超分子网络结构。化合物2中，[(Tp)Fe(CN)₃]^-通过其中的1个氰基与[Mn(D，L-Lb)]⁺桥联，其中Mn(Ⅲ)离子为六配位，分别和四齿配体Lb的2个氧原子和2个氮原子、DMF的1个氧原子及[(Tp)Fe(CN)₃]^-中的氰基氮原子配位。磁性研究表明，在化合物1中，Cu(Ⅱ)离子与Fe(Ⅲ)离子之间表现出铁磁相互作用，用哈密顿函数H=-2J(S₁·S₂+S₂·S₃)对其χ_MT-T曲线进行拟合，得到1的朗日因子g为2.190，交换常数J为0.55 cm^-1。     

氨·环己胺·羧酸根合铂(Ⅱ)类配合物的合成、抗肿瘤活性和与DNA的键合水平

本工作设计合成了6种新型氨·环己胺·羧酸根合铂(Ⅱ)类配合物[Pt(NH₃)((?)-NH₂)X₂](a～f){其中，X=CH₃COO^-(乙酸根)，CH₂ClCOO^-(氯乙酸根)，C₆H₅-COO^-(苯甲酸根)，p-CH₃O-C₆     

以5-(6-羧酸-2-萘基)-间苯二羧酸为配体构筑的两个镉的金属-有机骨架化合物的合成、晶体结构及荧光性质

在溶剂热条件下,以不对称三羧酸5-(6-羧酸-2-萘基)-间苯二羧酸(H₃L)为配体合成了2个镉的金属-有机骨架化合物:{[Cd₃L₂(H₂O)₃]·6DMF}_n(1)和{[Cd₃L₂(H₂O)₄]·3DMA}_n(2)。通过X射线单晶衍射,粉末衍射,热重和红外光谱进行了结构表征。结构分析表明,1和2形成3,6-连接的三维结构,其拓扑符号分别为:(4⁵.6⁴.8⁶)(4³)₂和(6¹².8³)(6³)₂。此外,还对2个化合物进行了荧光分析。     

过渡金属与新型硝基酚臂式氮杂18-冠-6配位性能的研究

合成并表征了1,10-二氧-4,7,13,16-四氮杂18-冠-6 (1)母体及其四取代硝基酚臂式衍生物 (2)。在H₂O-DMSO(V/V=1/4)混合溶剂中用UV-Vis光谱法对冠醚2与H⁺、Mn²⁺、Co²⁺、Ni²⁺、Cu²⁺、Zn²⁺、Cd²⁺和Hg^{2+相似文献}   

硫酸镉无机层和原位反应生成的吡啶基四氮唑有机配体构筑的两个层-柱状三维无机-有机杂化材料:合成和表征

以硫酸镉、叠氮化钠和4-氰基吡啶或3-氰基吡啶为反应物,在水热条件下,通过原位反应分别得到了2个基于硫酸根离子和5-(4-吡啶基)四氮唑(4-Hptz)或5-(3-吡啶基)四氮唑(3-Hptz)配体的,具有三维层-柱状框架结构的无机-有机杂化材料,即[Cd₂(H₂O)(OH)(SO₄)(4-ptz)]_n(1)和[Cd₂(OH)(SO₄)(3-ptz)]_n(2)。通过元素分析、红外光谱、热重分析以及单晶和粉末X-射线衍射分析对它们的组成和结构进行了表征。在配合物1和2的结构中,每个镉(Ⅱ)离子的配位数均为6,处于扭曲的八面体配位环境中,SO₄^2-和OH^-阴离子连接镉(Ⅱ)离子扩展形成碱式硫酸镉的二维无机阳离子层结构[Cd₂(H₂O)(OH)(SO₄)]_nⁿ+(1)或[Cd₂(OH)(SO₄)]_nⁿ+(2),相邻的二维无机阳离子层间再通过4-ptz^-(1)或3-ptz^-(2)进一步柱连接,形成三维层-柱状结构的无机-有机杂化框架结构。室温下的固体荧光实验表明,在350 nm的光激发下,配合物1和2分别在481和489 nm处出现强烈的荧光发射。     

核-壳结构磁性金属有机骨架材料Fe3O4@UiO-66-NH2的合成、表征及催化性能

UiO-66-NH₂是以Zr⁴⁺为金属,以2-氨基对苯二甲酸为配体制备得到的金属有机骨架材料,它是目前报道中具有较高热稳定性和化学稳定性的材料之一。本文以Fe₃O₄为核,以UiO-66-NH₂为壳,采用层层自组装方法制备了核-壳结构的磁性金属有机骨架材料Fe₃O₄@UiO-66-NH₂。利用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)和氮气吸附等对其进行了表征,并考察了该磁性材料在克脑文盖尔(Knoevenagel)缩合反应中的催化性能。结果表明,该磁性材料Fe₃O₄@UiO-66-NH₂为核-壳结构,壳层厚度约为100 nm,氨基含量为1.70 mmol·g^-1。该磁性复合材料具有Fe₃O₄和UiO-66-NH₂的双重功能,既可以磁性分离,又具有UiO-66-NH₂的孔结构和催化性能。由于壳层材料中Lewis酸性位(Zr⁴⁺)和碱性基团(-NH₂)的协同催化能力及其壳层的纳米尺寸,该磁性材料在Knoevenagel缩合反应中表现出和UiO-66-NH₂纳米粒子相当的催化活性。而且,通过磁性分离实现催化剂的多次循环使用后,其结构没有明显变化。     

On the radiation resistance of crown ethers

The yields of hydrogen and ethylene from the radiolysis of 15-crown-5, 18-crown-6, dibenzo-18-crown-6, and dicyclohexyl-18-crown-6 ethers have been measured. The quantities obtained are compared with the ones for PEG-300, PEG-600 and 1,4-dioxane measured under the same conditions. The hydrogen yields range from about 1 to nearly 2 molecules per 100 eV and these of ethylene range from 0.02 to 0.15 depending on the irradiation conditions. From the viewpoint of the rate of radiation decomposition, there is no much difference between crown ethers and their analogues including 1,4-dioxane, the simplest molecule in the series.     

冠醚化合物的合成——Ⅺ.新配体二茂铁硫冠醚的合成及其络合性能的初步研究

二茂铁硫冠醚的合成和性质的研究,近年来 Sato 等做了不少工作,其化合物的主要类型如下:     

The Solvation of Carbenes: π and O-Ylidic Complexes of p-Nitrophenylchlorocarbene

p-Nitrophenylchlorocarbene (PNPCC) was studied by laser flash photolysis with UV-vis detection in solution at ambient temperature. The π → p (316 nm) and σ → p (628 nm) absorptions of PNPCC were replaced in π- or O-donor solvents by absorptions due to π- or O-ylidic complexes or O-ylides. Donors included anisole, 1,3-dimethoxybenzene, 1,3,4,5-tetramethoxybenzene, diethyl ether, 18-crown-6, and dibenzo-18-crown-6. Suggestive evidence was also obtained for weak π-complexation of PNPCC by benzene. Computational studies aided in understanding the carbene complex and O-ylide absorption spectra, and they provided structures and energetics for these species.     

N-(4-amino-7-nitrobenzaoxa-1,3-diazole)-substituted aza crown ethers: complexation with alkali, alkaline earth metal ions and ammonium

Three novel aza-crown ether derivatives incorporating 4-amino-7-nitrobenzaoxa-1,3-diazole (NBD) chromophore were synthesized and their structure confirmed by ¹H-NMR, IR and elemental analysis. The influence of the solvent polarity and protonation on the photophysical properties of NBD-15-crown-5 was studied by UV/Vis and fluorescence methods. The influence of the investigated cations on the absorption spectra of the ligands was negligible, however emission was strongly affected. Complexation and binding stability of NBD-aza-15-crown-5 and NBD-aza-18-crown-6 were studied using fluorescence spectroscopy. NBD-aza-18-crown-6 exhibits strong selectivity toward Ca²⁺ and Sr²⁺ ions with formation constants about 10³ times higher than the formation constants with the other ions included in the study.     

The interaction between ketamine and some crown ethers in common organic solvents studied by NMR: the effect of donating atoms and ligand structure

1H NMR spectroscopy was used to investigate the stoichiometry and stability of the drug ketamine cation complexes with some crown ethers, such as 15-crown-5 (15C5), aza-15-crown-5 (A15C5), 18-crown-6 (18C6), aza-18-crown-6 (A18C6), diaza-18-crown-6 (DA18C6), dibenzyl-diaza-18-crown-6 (DBzDA18C6) and cryptant [2,2,2] (C222) in acetonitrile (AN), dimethylsulfoxide (DMSO) and methanol (MeOH) at 27 degrees C. In order to evaluate the formation constants of the ketamine cation complexes, the CH3 protons chemical shift (on the nitrogen atom of ketamine) was measured as function of ligand/ketamine mole ratio. The formation constant of resulting complexes were calculated by the computer fitting of chemical shift versus mole ratio data to appropriate equations. A significant chemical shift variation was not observed for 15C5 and 18C6. The stoichiometry of the mono aza and diaza ligands are 1:1 and 1:2 (ligand/ketamine), respectively. In all of the solvents studied, DA18C6 formed more stable complexes than other ligands. The solvent effect on the stability of these complexes is discussed.     

Single complexation force of 18-crown-6 with ammonium ion evaluated by atomic force microscopy

The cation complexation force of 18-crown-6 has been measured in ethanol by means of atomic force microscopy using probe tips and mica substrates modified chemically with 18-crown-6 and ammonium ion, respectively. The specific complexation force was suppressed by free potassium ion in the measurement solution, indicating a blocking effect based on the competitive complexation of the 18-crown-6 moiety between the free ion and the ammonium ion bound to the substrate. The single complexation force of 18-crown-6 with ammonium ion was evaluated to be about 60 pN in ethanol by autocorrelation analyses of the histograms for observed forces.     

Studies of Activity Coefficients for Ternary Systems: Water + 18-Crown-6 + Alkali Chlorides at 298.15 K

Osmotic vapor pressure measurements have been carried out for three ternary systems, H₂O + 0.2 m 18-crown-6 + LiCl, H₂O + 0.2 m 18-crown-6 + NaCl and H₂O + 0.2 m 18-crown-6 + KCl at 298.15 K using vapor pressure osmometry. Water activities for each ternary system were measured and used to calculate the activity coefficients of 18-crown-6 (18C6) and its salts following the methodology developed by Robinson and Stokes for isopiestic measurements. In the concentration range studied, it was found that (in NaCl and KCl solutions) there is considerable lowering of activity coefficients of one component in the presence of other solutes that has been attributed to the formation of the complexed 18C6:Na⁺ (or 18C6:K⁺) species in solution. The Gibbs energies of transfer of alkali chlorides from water to aqueous 18C6 solutions and that of 18C6 from water to aqueous electrolyte solutions have been calculated. These were further used to evaluate the pair and triplet interaction parameters. The calculation of thermodynamic equilibrium constants using the pair interaction parameter, g _NE (i.e., the nonelectrolyte–electrolyte pair interaction) for the studied complexation of cations yields values which are in good agreement with those reported in literature obtained by using ion-selective potentiometry and calorimetry. The results are discussed in terms of water structural effects, complex formation, and hydrophobic interactions.     

Specific features of the chemical behavior of acetylenic derivatives of benzocrown ethers

4"-Ethynylbenzo-12-crown-4 (8), 4"-ethynylbenzo-15-crown-5 (9), and 4"-ethynylbenzo-18-crown-6 (10) were synthesized by cross-coupling of the corresponding aryl iodides 1—3 with 2-methylbut-3-yn-2-ol (4a) followed by the retro-Favorsky cleavage of the resulting carbinols. Unlike the corresponding benzo-12-crown-4 derivative (5a), the cleavage of tertiary acetylenic alcohols of benzo-15-crown-5 (6a) and benzo-18-crown-6 (7a) requires more than one molar equivalent of KOH. Aminoalkylation of crown ether 8 gives Mannich bases, independently of the reaction conditions and the nature of amine. The aminomethylation of acetylenic crown ethers 9 and 10 with paraform—piperidine (morpholine) in the presence of CuCl yields 1,4-disubstituted buta-1,3-diynes (19, 20) rather than Mannich bases.     

Cooperativity of dynamics of 18-crown-6 molecule forming one-dimensional chain in Cs2(18-crown-6)3[Ni(dmit)2]2

Heat capacity of Cs2(18-crown-6)3[Ni(dmit)2]2 was measured by adiabatic calorimetry. A broad thermal anomaly was observed around 225 K. The entropy gain (about 52 J K(-1) mol(-1)) is much larger than that expected for twofold disordering of 18-crown-6 assumed in the previous structure analysis. The shape of thermal anomaly was qualitatively explained by a linear Ising model developed for cooperative disordering in polymers. The 18-crown-6 molecules forming a one-dimensional chain in the crystal are orientationally disordered with moderate cooperativity.     

Spectroscopic studies of the interaction between crown ethers and organic nitriles

The interaction of 18-crown-6 (18C6), diaza-18-crown-6 (DA18C6), and dithia-18-crown-6 (DT18C6) with acetonitrile and malononitrile was investigated using infrared spectroscopy, 1H and 13C NMR spectroscopy, and molecular modeling. The interaction between 18C6 and the nitriles involves hydrogen bonding between the CH3/CH2 protons of the nitriles and the ether oxygens of the crown. In contrast, the interaction between the organic nitriles and DA18C6 involves the nitrogen of the nitrile group and the N-H groups of the crown. Due to the bulkiness of the sulfur atoms of DT18C6, no interaction was observed to occur between acetonitrile and the crown.