三甘酰双二苄胺(钠离子选择性膜电极活性物质)的合成

冠醚对金属离子具有高选择性的络合活性,近十余年来发展很快。但是,冠醚也有其弱点:合成困难,产率低,价格昂贵。Simon和Vogtle等在本世纪七十年代又发掘了开链冠醚:(醚型开链冠醚)和(酰胺型开链冠醚)等。开链冠醚除具有选择性络合金属离子的特点之外,还具有易于合成、结构富于变化等优点。酰胺型开链冠醚现已有数种可作为离子选择性膜电极的活性物质。开链冠醚三甘酰双二苄胺是钠离子选择性PVC膜电极的活性物质,其合成方法文献中未见有具体记载。据报导,三甘酰双二苄胺的类似物三甘酰双二苯胺是在大过量吡啶存在下用Einhorn酰化反应制得的。但我们在重     

铅(Ⅱ)离子印迹复合膜对重金属离子的吸附热力学与吸附动力学

以聚丙烯微孔膜(MPPM)为支撑,通过物理包埋和紫外线诱导共价键合组合法固定二苯甲酮,再通过紫外线引发丙烯酸和乙二醇二甲基丙烯酸酯接枝共聚制备了Pb(Ⅱ)离子印迹复合膜。采用平衡吸附和竞争渗透实验考察了印迹复合膜对Pb(Ⅱ)离子的吸附与选择能力。结果发现,印迹复合膜对Pb(Ⅱ)具有良好的吸附及渗透选择性,其对Pb(Ⅱ)的饱和吸附量分别为Cu(Ⅱ)和Zn(Ⅱ)的2.86倍和2.75倍,48 h的渗透量分别为Cu(Ⅱ)和Zn(Ⅱ)的3.8倍和3.1倍;Langmuir等温吸附模型与平衡吸附数据相当吻合(R²≥0.991),吸附属于单分子层吸附;动力学研究结果表明,印迹复合膜对重金属离子的吸附过程符合Lagergren准二级动力学模型(R²≥0.998,ΔQ<10%),吸附过程主要受化学作用控制;印迹复合膜对重金属离子的吸附自由能变(ΔG)、吸附焓变(ΔH)及吸附熵变(ΔS)均为负值,说明吸附是一个自发、放热的过程;|ΔH|>|TΔS|,表明吸附过程是一个焓驱动过程。     

基于冠醚的离子识别响应型智能材料研究新进展

金属离子对生物体的生命活动起着核心的作用,而一些重金属离子(如Pb²⁺、Hg²⁺)在很低浓度时就对生物具有极强的毒性;因此,研究具有金属离子识别特性的智能材料具有重要的理论价值和实用意义。冠醚具有选择性地络合金属离子的能力,研究者们将冠醚的离子识别特性与聚(N-异丙基丙烯酰胺)的相变行为特性相结合制备了一系列离子识别响应型智能材料。综述了近年来基于18-冠-6和15-冠-5两种冠醚分子的离子识别响应型智能材料的研究新进展。目前,基于冠醚的离子识别响应型智能材料仍多处于基础研究阶段,还需要进一步系统深入研究和开发完善。     

离子载体分离锂离子研究评述(I)——在均相溶液中锂离子与离子载体的络合作用

阐明了络合与逆络合的比率常数、稳定常数及其方程等概念然后就多足配体(Podands)、冠状配体(Cornands)、和穴状配体(Cryptands),在具体的实验条件下,与碱金属及碱土金属阳离子进行络合作用的稳定常数及选择性分别进行了对照与比较.     

巯基功能化磁性纳米材料去除水中Ag(I)和Cd(II)

以3-巯基丙基三甲氧基硅烷为改性剂,对Si O_2包覆Fe_3O_4纳米粒子(Fe_3O_4@Si O_2)进行改性,制备了表面巯基化磁性纳米吸附材料(Fe_3O_4@Si O_2-RSH),对其进行了表征,并研究了其对水中痕量Ag(I)和Cd(II)的吸附性能。结果表明,Fe_3O_4@Si O_2-RSH能够通过其表面巯基的螯合离子交换作用,在p H为4.0~8.0内快速、高效的吸附溶液中痕量Ag(I)和Cd(II),且受溶液中Na(I)、Ca(II)、Fe(II)等共存离子影响较小。发生在Fe_3O_4@Si O_2-RSH表面的单层吸附能够在10 min内达到平衡,Ag(I)和Cd(II)的去除率均90%;被吸附的Ag(I)和Cd(II)能够被HNO_3溶液或L-半胱氨酸溶液洗脱并回收,回收率83%。Fe_3O_4@Si O_2-RSH可以作为高效的吸附剂,用于污水中痕量Ag(I)和Cd(II)的深度处理和资源化回收利用。     

冠醚化学研究的新进展

介绍了冠醚类化合物的结构特点及络合性能、冠醚的络合作用和识别分子离子的新进展。重点综述了近几年各类新冠醚化合物的合成、配合物的形成、对分子离子的识别、选择性络合及新应用,展望了其广阔的应用前景,期望能在医药学、生命科学、材料科学、环境科学及能源科学的应用方面更有意义。     

新型吡啶冠醚的全合成

吡啶基冠醚是一类具有重要生理活性的冠醚类化合物。本文拟定了一条以基本原料合成冠醚的路线。并成功地合成出新型吡啶基冠醚——3,5’-(2’,6’-二甲基吡啶)-18-冠醚-5(V)。络合迁移试验表明,它对钾离子良好的选择性络合迁移性能。     

液相羰基法合成碳酸二甲酯的铜络合催化剂

用溴化铜和季铵盐制备了络合催化剂,并考察了几种无机盐助荆对催化剂性能的影响.结果表明.络合催化剂CuxBrnLm对甲醇液相氧化羰化合成碳酸二甲酯(DMC)具有良好的催化活性,以碳酸钾为助剂时,甲醇转化率达到了26.9%,DMC选择性达到97.8%.采用傅立叶红外光谱(FT-IR)、X射线衍射(XRD)、元素分析(EA)和电感耦合等离子发射光谱(ICP-AES)对合成的催化剂进行表征,结果表明,络合催化剂的分子式为Cu2Br62,配位剂和无机盐助剂有助于形成甲醇选择性氧化羰基合成DMC的活性物种Cu(I),而Cu(I)是催化剂活性中心.     

用pH电位法测定Yb(Ⅲ)-苹果酸络合物的稳定常数

在分析化学中所使用的大部分络合配位基,多为中强碱,在一定的pH下可以质子化。金属离子与已质子化的配位基形成络合物而同时释放出质子,因此,测量滴定过程中体系pH的变化,根据酸碱平衡与络合平衡,可测得络合物的稳定常数。苹果酸为二元弱酸(H_2L),与Yb(Ⅲ)络合形成[YbL~ ],[YbL_2~-]和[YbL_3~(3-)]络合物。根据电荷等衡与质量等衡,可计算出在不同中和度a下,体系中游离配位基的浓度[L~(2-)]及平均配位数n,按照实验获得的各个[L~(2-)]和n值,绘制-log[L~2]和n的关系曲线,由半值点法确定各级稳定常数。为了获得更为精确的数值,可用松弛法对实验数值进行校正。苹果酸与Yb(Ⅲ)所形成络合物的第一级稳定常数K_1,在研究了测定体     

富马酰基桥联双冠醚的晶体结构及其对金属离子的选择键合

通过母体冠醚环(苯并氮杂-15-冠-5)与富马酰氯反应,合成了一种新型的富马酰基桥连的双冠醚,其单晶结构经X-射线单晶衍射仪测定;继而采用溶剂萃取法考察了其对金属离子(Li~+、Na~+、K~+、Rb~+、Cs~+、Ag~+、Tl~+)的识别能力。结果显示,该双冠醚对Li~+具有较高的萃取率和选择性。     

冠醚化合物对乳剂晶体外延生长的调变作用

本工作研究了冠醚化合物在外延乳剂生长过程中的调变作用。结果表明，１，４，７，１０，１３，１６－六氧杂环十八烷对ＡｇＢｒ八面体乳剂无侵蚀作用，对非同晶系晶体之间的外延不起调变作用。１，７，１０，１６－四氯－４，１３－二氮代杂环十八烷均使ＡｇＢｒ八面体乳剂的棱角产生了不同程度的侵蚀，可充当不同晶系晶体外延生长的调变剂，对晶体的溶解侵蚀能力依２Ｓ－１８－Ｃ－６，２Ｎ－１８－Ｃ－６，１８－Ｃ－６的次序降低     

Synthesis,complexation and biological effects studies of new thiacrown ethers derived quinoline: part I

A series of new thiacrown ethers derived quinoline 7–9 were synthesized in good yield and in a simple way. Their transition metal ions complexation was studied using a conductometric method in acetonitrile at 25°C. Crowns 7 and 8 showed a continuous decrease in the molar conductances in their complexation with Ag⁺, Cu²⁺, Hg²⁺ and Zn²⁺ which begins to level off at a molar ratio of 1:1 crown to metal, indicating the formation of 1 stable 1:1 complex. On the other hand, crown 9 showed the formation of 1:1 complexes only with Ag⁺, Cu²⁺, Hg²⁺. The in vitro, a preliminary antimicrobial, antioxidant and cytotoxic effects on breast tumor cells were also reported. Five bacterial test strains were included in the present study. Antioxidant activity was measured in terms of the radical scavenging ability and decolorization of 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radicals. Cytotoxic effect of thiacrown was evaluated using MDA MB-231 cell line (human breast adenocarcinoma, ATCC HTB-26).     

Studies of the Size-Selective Extraction of Alkali Metal Ions by the Synergistic Extraction System,Crown Ether-DI(2-Ethylhexyl) Phosphoric Acid-Benzene

Abstract

In order to take practical advantage of the size-selective cation-coordinating ability of the cyclic polyethers (crown ethers), experiments seeking a means of avoiding the problem of solubilizing a mineral-acid anion in a nonpolar organic diluent were performed. Mixtures of several known extractants and crown ethers were tried. Results presented indicate that organic soluble cation exchangers mixed in solution with crown ethers produce a synergistic extractant mixture that largely exhibits the size-selective properties expected of the crown ether. Data are presented for the extraction of macro concentrations of alkali metals by di(2-ethylhexyl) phosphoric acid—dicyclohexyl-18-crown-6 mixtures at a single pH, and at nonloading condition(σ metal cone < 0.04 M) as a function of pH, 2 to 6. In both cases potassium is synergized most strongly presumably because of its best fit to the crown ether cavity. Other data indicate, however, that the size-fit principle is not as consistent for all alkali metal ions and crown ethers as for potassium and dicyclohexyl-18-crown-6. Other effects such as competition for ion hydration and aqueous-phase distribution of the complex may have important effects that have not been elucidated.     

双套索硫杂冠醚及主链含硫杂冠醚聚酯的合成

从３，１６－二羟基－１－硫杂－５，３，１１，１４－四氧杂环十七烷（二羟基硫杂－１７冠－５）出发，通过醚化反应，合成了双（己氧基），双（十二烷氧基）、双（十六烷氧基），双（苄氧基）和双（烯丙氧基）硫杂－１７－冠－５。单己氧基、单十二烷氧基，单十六烷氧基和单苄氧基硫杂－１７－冠－５作为副产物分离得到。通过二羟基硫杂－１７－冠－５与丁二酰氯缩聚，合成了主链含硫杂冠醚的聚酯。     

LIQUID-LIQUID EXTRACTION OF Ag(I), Hg(II), Au(III) AND Pd(II) BY SOME OLIGOTHIA MACROCYCLIC LIGANDS INCORPORATING AROMATIC AND HETEROAROMATIC SUBUNITS*

ABSTRACT

A series of hydrophobic tri- to hexa-dentate sulfur containing macrocyclic ligands incorporating aromatic and heteroaromatic subunits have been studied with respect to their extraction properties toward Ag(I), Hg(II), Au(III), and Pd(II) in aqueous//organic systems. The stoichiometry of extracted species and their extraction constants have been determined. The different ligands are compared with structure related open-chain compounds. The influence of substitution, solvent, and anion on the extraction equilibrium is also discussed providing a basis for future design of selective extractants and for die development of improved separation methods. The extractability of the various metal ions strongly depends on the nature and the number of donor atoms of the corresponding ligands and on the properties of the metal ion itself. In some cases, simple open-chain ligands show extraction properties comparable to the present macrocycles. A trithia crown with incorporated benzo subunit highly prefers Ag(I) to Hg(II). Furthermore a distinct selectivity for Au(ni) and Hg(II) over Pd(II) with pyridine substituted macrocycles was found.     

LIQUID-LIQUID EXTRACTION STUDIES OF METAL IONS WITH DITHIACROWN COMPOUNDS

The extraction properties of dibenzo-1, 10-dithia-[18]crown-6 compounds have been investigated. Especially thiophilic metals are effectively extracted. The extraction of Ag(I), Pd(II) and Au(III) is much greater than that of Hg(II) or Cu(I). Alkali and alkaline earth metals are not extracted. The experimental results show the coordination of metal ions with sulfur is decisive for the extraction. The variation of the subetituents at the macrocyclic ring from CH₃- t o CH₂Cl-groups influences the extraction power considerably. In contrast, the substitution on the benzo groups shows a less strong effect. The influence of diluents and counter anions on extraction are comparable with results in known crown ether systems. Synergistic extraction is observed for silver and mixtures of dithiacrown compounds and HDEHP, n-caprylic acid or TBP.     

Upper Rim Thioether Derivatives of Calix[4,6]Arenes: Extraction of Fission Pd(II) and Ag(I)

Abstract

We report studies on the Pd(II) and Ag(I) complexation and extraction by tetraalkyl(tolyl)thiomethylcalix[4]arenes (1a–c) stabilized in the cone conformation, and by the stereochemically mobile tetraalkyl(tolyl)thiomethylcalix[6]arenes (2a, b). These are found to be 100–1000 times more efficient as extractants of nitric and nitrous forms of Pd(II) and Ag(I) than their ungrafted monodentate analogues. Extraction experiments performed on real HLW show that tetrabutylthiomethylcalix[4]arene 1b is able to concentrate and separate Pd from main fission products. The extraction constants for mono‐ and binuclear Ag complexes have been determined. The stoichiometry and structural features of the complexes of Pd and Ag have been studied experimentally by extraction, IR‐ and mass‐spectroscopy methods as well as in quantum‐mechanical calculations.     

RING-SIZE AND SUBSTTTUENT EFFECTS IN THE SOLVENT EXTRACTION OF ALKALI METAL NITRATES BY CROWN ETHERS IN 1,2-DICHLOROETHANE AND 1 -OCTANOL

ABSTRACT

The extraction of alkali metal nitrate salts by solutions of crown ethers in each of the two diluents 1,2-dichlorethane and 1-octanol has been surveyed. The crown ethers include 18-crown-6, 21-crown-7, and 24-crown-8 ethers bearing cyclohexano, benzo, t-alkylbenzo, and/or furano substitutents. The extraction efficiencies of the different crown ethers are examined in terms of ring-size, substituent, and solvent effects. Partition ratios for the crown ethers between water and either 1,2-dichloroethane or 1-octanol are discussed. The extraction selectivities, expressed as the separation factor for cesium over sodium, are examined in relation to crown ether structure.     

蓬勃发展的冠醚化学

简要介绍了冠醚的结构、性能,冠醚化学的产生、发展及应用。重点介绍了：①新型冠醚及其金属配合物的合成;②新型冠醚的选择性络合及其自组装;③新型冠醚的络合作用及催化作用。并展望了其广阔的应用前景。