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以3类含不同基团的杯[4]芳烃衍生物作为离子载体在H2O-CHCl3-H2O液膜传输体系下分别对Pb2+进行液膜传输实验. 简要讨论了以杯[4]芳烃衍生物作为离子载体对Pb2+液膜传输的动力学机理. 重点研究了不同载体种类, 载体浓度, 搅拌速度, 传输时间等因素对Pb2+传输的影响. 实验结果表明: 以含Br原子的杯[4]芳烃衍生物和含S原子的杯[4]芳烃衍生物作为离子载体对Pb2+有明显的传输效果. 可以用本文的动力学模型来描述整个传输体系的动力学特性. 相似文献
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硫杂杯[4]芳烃衍生物的合成及萃取性能研究 总被引:1,自引:1,他引:0
通过两个不同的平台合成了一系列结构新颖的硫杂杯[4]芳烃衍生物,阳离子萃取试验表明该硫杂杯[4]芳烃衍生物比含有相似官能团的杯[4]芳烃衍生物具有更好的软金属离子萃取性能,新化合物的结构经IR, 1H NMR,MS和元素分析等证实. 相似文献
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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。 相似文献
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以吗啉和六氢吡啶修饰的四种对叔丁基杯[n]芳烃酰胺类衍生物(n=6,8)为萃取试剂,研究了它们对Na+,K+及部分过渡金属等十种金属离子的萃取作用.结果表明此类杯芳烃酰胺类衍生物对过渡金属离子有良好的选择性识别作用.其中,吗啉取代基修饰的杯[8]芳烃萃取效果最好. 相似文献
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A series of novel N-chromogenic calix[4]arene azacrown ethers were synthesized as selective extractants of potassium ion. 1,3-Alternate calix[4]arene azacrown ethers were prepared by reacting 25,27-dipropyloxy-26,28-bis(5-chloro-3-oxapentyloxy) calix[4]arenes with p-toluenesulfonamide in the presence of potassium carbonate. The coupling reaction of calix[4]arene azacrown ether with 2-hydroxy-5-nitrobenzyl bromide in the presence of triethylamine in THF gave the chromogenic calix[4]arene azacrown ether in moderate yield. These compounds show high potassium selectivity over other metal ions as shown by two-phase extraction, bulk liquid membrane, and 1H NMR studies on a ligand-metal complex. It is assumed that the OH of the chromogenic group attached on nitrogen can assist the complexation by encapsulation of the metal. 相似文献
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Calix[4]arene-capped [3-(2-O-beta-cyclodextrin)-2-hydroxypropoxy]propylsilyl-appended silica particles (C4CD-HPS), a new type of substituted beta-cyclodextrin-bonded chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC), have been synthesized by treatment of bromoacetate-substituted [3-(2-O-beta-cyclodextrin)-2-hydroxypropoxy]propylsilyl-appended silica particles (BACD-HPS) with calix[4]arene oxyanions in anhydrous N-methyl-2-pyrrolidone. The synthetic stationary phase is characterized by means of elemental analysis. This new type of CSP has a chiral selector with two recognition sites: calix[4]arene and beta-cyclodextrin (beta-CD). The chromatographic behavior of C4CD-HPS was studied with several disubstituted benzenes and some chiral drug compounds under reversed-phase conditions. The results show that C4CD-HPS has excellent selectivity for the separation of aromatic positional isomers and enantiomers of chiral compounds due to the cooperative functioning of calix[4]arenes and beta-CDs. 相似文献
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Iglesias-Sánchez JC Wang W Ferdani R Prados P de Mendoza J Gokel GW 《Nouveau journal de chimie》2008,32(5):878-890
An earlier study showed that a calix[4]arene could function as a central relay unit to form an ion conductance pathway through a phospholipid bilayer membrane. The present study expands the range of compounds from calix[4]arene to calix[6]arene and incorporates them either as central units or as headgroups, substituting one or more diaza-18-crown-6 residues in functioning hydraphiles. Ion release was assayed by detecting either Na(+) or Cl(-) release from phospholipid vesicles. The ion transport activity for calix[4]arenes in either position is modest, but is almost non-existent when calix[6] residues were incorporated either as head groups or central relay units. The poor activity of the calix[6]arenes may result from an inability to penetrate to the midplane of the bilayer or pass entirely through it to form a conductance pathway. The transmembrane "flip-flop" may result from high polarity or steric bulk, or both. A hydraphile incorporating a single -NHCOC(6)H(4)OCH(2)CONH- as a central relay proved to be an excellent Na(+) conductor, but less selective for Cl(-). The fact that this new hydraphile molecule shows selectivity for Na (+) over Cl(-) transport and possesses two secondary amide residues in the central relay suggests a means to control ion selectivity in synthetic ion transporters. 相似文献
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Zeng X Sun H Chen L Leng X Xu F Li Q He X Zhang W Zhang ZZ 《Organic & biomolecular chemistry》2003,1(6):1073-1079
Two novel tweezer-like 25,27-dihydroxy-26,28-bis(phenylthiaethoxy)calix[4]arenes 6 and 7 were synthesized by the reaction of 25,27-dihydroxy-26,28-bis(bromoethoxy)calix[4]arenes 3 and 4 for the evaluation of their ion-selectivity in ion-selective electrodes (ISEs). X-ray structural analysis indicated that calix[4]arene 7 is in an interesting infinite linear aggregate via self-inclusion. For investigation of the influences of substitutes on the behavior of the ISEs, the halogen substituted aryl analogues of 25,27-dihydroxy-26,28-bis(arylthiaethoxy)calix[4]arenes 8-12 were also synthesized and their ISE performances were evaluated under the same conditions. ISEs based on 6-12 as neutral ionophores were prepared, and their selectivity coefficients for Ag+ (log KAg,M(pot)) were investigated against other alkali metal, alkaline-earth metal, lead, ammonium ions and some transition metal ions using the fixed interference method (FIM). These ISEs showed excellent Ag+ selectivity over most of the interfering cations examined, except for Hg2+ having relative smaller interference (log KAg,Hg(pot) < or = 2.1). The 19F NMR spectra of 9 and 9.AgClO4 were recorded for investigation the fluorine environments in the complex. The 19F NMR spectra strongly suggested that the fluorine atoms on ionophore 9 participated in ligation with silver cation. 相似文献
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Maria N. Agafonova Olga A. Mostovaya Igor S. Antipin Alexander I. Konovalov Ivan I. Stoikov 《Mendeleev Communications》2012,22(2):80-82
Selective transmembrane carriers for a-hydroxy acids, acyclic a-amino phosphonates and calix[4]arenes containing a-aminophosphonate substituents at the lower rim have been synthesized; analytical HPLC has been used to monitor the selective separation of dicarboxylic, a-hydroxy and a-amino acid mixtures by membrane extraction; the attachment of a-aminophosphonate fragments to the macrocyclic calix[4]arene platform results in receptors with markedly modified efficiency and selectivity relative to those of only aminophosphonates. 相似文献
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Arisa Jaiyu 《Tetrahedron letters》2007,48(10):1817-1821
A series of stilbene-bridged calix[4]arenes was synthesized through an intramolecular reductive McMurry coupling of bisbenzaldehyde calix[4]arene in high yields. Tetra- and pentaethylene glycol chains were tethered to the phenolic groups of calix[4]arene to form stilbene-bridged calix[4]arene crown-5 and crown-6, respectively. The presence of stilbene bridge over the calix[4]arene rim effectively prevented the connection of the polyether chains in the cone conformation resulting in the exclusive formation of 1,3-alternate stilbene-bridged calix[4]arene crown product. Compared to the cone analogues, the 1,3-alternate calix[4]arene crown ethers showed a greater extraction ability and selectivity toward Cs+. 相似文献
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Sergey N. Podyachev Svetlana N. Sudakova Victor V. Syakaev Azat K. Galiev Roald R. Shagidullin Alexander I. Konovalov 《Supramolecular chemistry》2013,25(5):479-486
The binding properties of the cone conformer of O,O,O,O-tetrakis[hydrazinocarbonylmethyl]-4-tert-butylcalix[4]arene, the cone and the 1,3-alternate conformers of the corresponding thia analogue have been evaluated by means of liquid–liquid extraction for a large variety of metal ions. The extraction constants and the stoichiometries of the complexes formed have been determined. Comparison of the extraction properties of calix[4]arenes with their acyclic monomeric analogue clearly demonstrated, that the preorganization of acetylhydrazide groups on the calix[4]arene platform is the cause for a significant improvement of its binding properties. The presence of additional “soft” nitrogen binding sites in acetylhydrazide derivatives of calix[4]arenes compared to their amide derivatives leads to a shift from their classical selectivity for alkali and alkaline earth cations to transition metals. The cone conformer of tetrathiacalix[4]arene shows higher selectivity in a series of d-metal ions compared with its “classical” analogue. The 1,3-alternate conformer exhibits an excellent extraction selectivity for Cu2+ and Hg2+. 相似文献
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《Analytical letters》2012,45(5):831-845
ABSTRACT Potentiometric behaviors of a salt-bridge supported bilayer lipid membrane (Sb-BLM) modified with Calix[n]arene (n=4, 6, 8) derivatives are described for some alkali metal ions. The modified Sb-BLM was used as an alkali cation sensor. The membrane potentials were observed to generate Nernstian responses to the concentration of alkali metal ions in electrolyte. The Sb-BLM modified with the calix[n]arenes show high selectivity for individual alkali metal ions: Calix[8]arenes for K+, calix[6]arenes for Cs+ Calix[4]arenes show no selectivity for any alkali ions. The interacting mechanism is also discussed. 相似文献
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《Analytical letters》2012,45(5):768-775
Nine series of chromogenic mono- (A1-A2) and di- (B1-B7) substituted azocalix[4] arene analogues containing more than one azo group were described. Different chelating agents like ester and ketone moieties were grafted on the lower rim position of azocalix[4]arenes. The selective extraction properties of Fe3+ cation were studied by liquid-liquid extraction. This extraction process was carried out by using compounds A1-A2 and B1-B7. The results proved that coupling of phenylazo groups onto the upper rim of azocalix[4]arenes yielded greater efficiency and selectivity for carrying the Fe3+ cation in the extraction process at pH 2.2. 相似文献
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Naturalmacrocycliclactonesandlactamsastheionophoreshaveabsorbedextensiveinterestsbecauseoftheirveryhighselectiverecognitionforalkalimetals.rorexample,nactinslandvalinomycin'havethehighestselectivityforpotassiumamongalltheionopohores.Artificialmacrocycliclactonesalsoshowedselectivityforcanons,althoughthebindingstrengthwaslowerthanthatofcommoncrownethers3.Calixareneswereaveryimportantkindofartificialreceptors,whosederivativeshaveshowedthehighestselectivityforNa ,K andCs amongthesynthesizedmacro… 相似文献