含苯并氮杂15-冠-5侧基的线型聚硅氧烷促进液膜离子传输性能

N-十一碳烯和N-烯丙基苯并氮杂15-冠-5和甲基二氯硅烷硅氢加成后, 再与端羟基聚二甲基硅氧烷反应, 用三甲基氯硅烷封端, 合成了两种含苯并氮杂15-冠-5侧基的线型聚硅氧烷。分别以两种聚合物为液膜离子传输载体, 研究了载体种类、阴离子、阳离子种类及载体浓度和盐浓度对离子传输速率的影响, 并考察了膜的稳定性。     

具有二苯并18－冠－6侧基的线型聚硅氧烷的合成及其促进离子传输性能

具有二苯并１８－冠－６侧基的线型聚硅氧烷的合成及其促进离子传输性能龚淑玲，卢雪然，卢光明，陈远荫（武汉大学化学系武汉４３００７２）关键词冠醚，聚硅氧烷，离子载体，液膜具有冠醚基团的线型聚硅氧烷是一类用作毛细管色谱固定相￣［１］、高选择性液体萃取剂￣［...     

新型吡啶基冠醚液膜离子选择电极的制备及其性能研究

离子选择电极是分析测试中有用的电化学传感器。它在分析化学中很多领域都有重要用途,尤其是对低浓度离子的测定,具有灵敏、快速简便的优点。本文将自己合成的新型吡啶基冠醚(Ⅰ)作为中性载体,制成PVC液膜钾离子选择电极,并研究了它的响应性能。     

聚硅氧烷冠醚做气相色谱固定液的研究

自从Pedersen首次发现冠醚能和金属离子形成稳定的络合物之后,冠醚在分析化学中得到了广泛的应用。它在液相色谱中的应用开发较早。低分子冠醚在气相色谱中的应用在1985年首先由李如松报道。Zagorevskaya等人则把低分子冠醚涂渍在碳分子筛上分离各种烷烃、芳烃和含氯化合物。金永浩等用武汉大学环科系合成的漆酚冠醚涂渍成毛     

杂元素冠醚研究（Ⅻ）——氧,硫,硒和碲杂冠醚的液膜迁移性能…

报道了碲杂冠醚（ＴｅＢ１５Ｃ５）对Ｎａ＾＋、Ｋ＾＋、Ａｇ＾＋和Ｐｂ＾２＋的液膜迁移能力，并与相应的全氧冠醚（Ｂ１５Ｃ５）、硫杂冠醚（ＳＢ１５Ｃ５）和硒杂冠醚（ＳｅＢ１５Ｃ５）作了比较；同时以ＳｅＢ１５Ｃ５对Ｋ＾＋的迁移为例考察了冠醚浓度和盐浓度对迁移速率的影响。     

杯[4]冠醚对过渡金属离子的液膜传输行为

藉杯芳烃衍生物的识别作用可以实现对金属离子的选择性液膜传输,本文研究了4种新型杯[4]冠醚对5种过渡金属离子（Cu^2 ,Fe^3 ,Co^2 ,Ni^2 ,Zn^2 ）的液膜传输行为,发现其中酯型杯[4]冠醚（Ⅲ）对Cu^2 有优良的传输效能,并考察考察了各种因素（包括源相和受相酸度、离子载休Ⅲ的浓度、时间及温度等）的影响,指出载体Ⅲ对C ^2 的传输为H^ 交换机理,并对该过程进行了初步解释。     

冠醚配合物的研究 XIII.三种大环配体液膜传输碱金属离子的动力学

本文报道以2,3-苯并-11-甲基-18-冠-6,2,3-苯并-8,15-二甲基-18-冠-6和2,3-苯并-8,11,15-三甲基-18-冠-6为液膜载体,研究其对碱金属离子的传输,发现当水相金属盐浓度和膜相配体浓度相近时,金属离子的传输为串联一级反应,求得了串级速率常数,并讨论了传输速率和配位作用的关系及载体结构的影响.     

Liquid Membrane Transport Behavior of Functional Substituted Crown Ethers for Amino Acids

Crown compounds offer a variety of interesting functions based on their specific bindings of organic guest species1,2. In particular, they can act as carriers in ion- extraction, membrane transport, and phase-transfer reactions. In contrast to the large variety of synthetic ionophores for cation transport, there are only a few examples of synthetic anion transport ionophores. Therefore, it appears highly desirable to search for a new class of ionophores with excellent transport abilities fo…     

SYNTHESIS OF LINEAR POLYSILOXANE WITH PENDANT BENZO－15－C－5 MOIETIES AND ITS TRANPORT PROPERTIES IN BULK LIQUID MEMBRANE SYSTEM

ＳＹＮＴＨＥＳＩＳＯＦＬＩＮＥＡＲＰＯＬＹＳＩＬＯＸＡＮＥＷＩＴＨＰＥＮＤＡＮＴ　ＢＥＮＺＯ－１５－Ｃ－５ＭＯＩＥＴＩＥＳＡＮＤＩＴＳＴＲＡＮＰＯＲＴＰＲＯＰＥＲＴＩＥＳＩＮＢＵＬＫＬＩＱＵＩＤＭＥＭＢＲＡＮＥＳＹＳＴＥＭＣＨＥＮＹｕａｎｙｉｎ；Ｌｕ...     

LINEAR POLYSILOXANE WITH DIBENZO-18-CROWN-6 MOIETIES AS LIQUID MEMBRANE CARRIER

A modified method of preparing crown functionalized linear polysiloxane has beendescribed. 4'-Allyldibenzo-18-crown-6 was subjected to hydrosilylation withmethyldichlorosilane, followed by polycondensation with silanol-terminatedpolydimethylsiloxane to give the title crown functionalized linear polysiloxane. Thetransport properties of sodium, potassium, and ammonium salt through a bulk liquidmembrane system using the new type of crown functionalized linear polysiloxane as acarrier were investigated. It is worthy to point out that the carrier can be used repeatedlyat least six runs with no apparent change in the transport rate of potassium ion.     

单臂冠醚的结构与液晶性质

设计并合成了３个低温冠醚液晶－单臂脂环冠醚液晶，考察了冠醚结构与液晶性质的关系，单臂冠醚液晶分子具有液晶蛋白质应满足长径比大于３，分子具有一定的平面特性和能通过引入手性基团使单臂冠醚液晶分子产生手性近晶相等条件。     

单臂冠醚结构与液晶性质

设计并合成了4个单臂冠醚液晶,考察了冠醚环与亲酯性结构单元之间的桥键与液晶性质的关系,中心桥键对单臂冠醚液晶的熔点影响不大,而对液晶热稳定性有较大的影响.     

Chiral Discrimination of Amino Acids by an Optically Active Crown Ether Studied by HPLC, Extraction and a Liquid Membrane Transport Experiments

A chiral crown ether incorporating a methyl -d-mannopyranoside unit displayed pronounced enantioselection of amino acids in partition liquid chromatography experiments involving solvent systems of limited miscibility: water–ethanol–2,2,4-trimethylpentane. The same system has been used for amino acid transport across a liquid membrane containing the crown ether, and in liquid–liquid extraction experiments. Remarkable enantioselection has been noted for amino acids in all the processes studied.     

Spectral Properties of Extracted Complexes of MetalPicrates with Crown Ethers

The investigation on UV-visible spectra of species formed by extracting some metal picrates with benzo-15-crown-5(B15C5) and dibenzo-18-crown-6(DB18C6) verified that there are some interactions of picrate anion with K , Na and rare earth ions in loaded organic phase. By the study of the charge transfer band and absorption spectra of picrate anion, it can be determined whether an ion pair has been formed and either a 1 : 1 contact ion pair or a 1 : 2 crown-separated ion pair involved in organic phase can be distinguished for an ion-pair extraction.     

Hydrogen-bonded Networks in Crown Ether Complexes of Hydrated Metal Ions

Abstract

The hydrated metal nitrates (M(NO₃)₃.6H₂O, M[dbnd]Co, Ni, Cu, Zn and Cd) have been crystallised from water in the presence of 18-crown-6 and their structures determined by X-ray crystallography. In the case of copper, a pseudo four-coordinate square planar complex resides in an extended six-coordinate octahedral array which is further bound in a single-stranded one-dimensional hydrogen bonded polymeric mode. For M[dbnd]Co,Ni,Zn and Cd isomorphous complexes are isolated where the octahedral [M(H₂O)₅(NO₃)⁺ cation resides in a two-dimensional polymeric network through hydrogen bonds between the water ligands and either the crown ether oxygens or unbound nitrate ions or water molecules.     

Preparation and Application of Cholesteryl‐Benzo‐15‐Crown‐5/Cholesteryl Mixed Liquid Crystals

Various mixed liquid crystals containing crown ether‐cholesteryl liquid crystal, benzo‐15‐crown‐5‐COO‐C₂₇H₄₅ (B15C5‐COOCh), with various common cholesteric liquid crystals, e.g., cholesteryl chloride, cholesteryl benzoate and cholesteryl palmitate, were prepared and studied using polarizing microscopy and differential scanning calorimetry. Investigating the concentration effect of B15C5‐COOCh in mixed liquid crystals revealed that the addition of B15C5‐COOCh resulted in wider phase transition temperature ranges of these cholesteryl liquid crystals. The stability of these B15C5‐COOCh/cholesteryl mixed liquid crystals was studied using comprehensive graphic molecular modeling computer programs (Insight II and Discover) to calculate their molecular energy and stability energy. The effect of salts, e.g. Na⁺, Co³⁺, Y³⁺ and La³⁺, on the transition temperature range of the mixed liquid crystals was also investigated. The crown ether cholesteric liquid crystal B15C5‐COOCh was applied both as a surfactant and an ion transport carrier to transport metal ions through liquid membranes. Cholesteryl benzo‐15‐crown‐5 exhibited distinctive characteristics of a surfactant and the critical micellar concentration (CMC) of the surfactant was investigated by the pyrene fluorescence probe method. Cholesteryl benzo‐15‐crown‐5 was successfully applied as a good ion transport carrier (Ionophore) to transport various metal ions, e.g. Li⁺, Na⁺, La³⁺, Fe³⁺ and Co³⁺, through organic liquid membranes. The transport ability of the cholesteryl benzo‐15‐crown‐5 surfactant for these metal ions was in the order: Co³⁺ ≥ Li⁺ > Fe³⁺ > Na⁺ > La³⁺.