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1.
Studies on extraction equilibrium constants at different temperatures and thermodynamic parameters of solvent extraction of Pb2+ ion with carboxylic acid derivatives of different ring size calixarenes and structure related monomeric compound have been carried out. The extraction equilibrium constants corresponding to calix[n]arene (n?=?4, 5, 6) derivatives decrease in the order [5]arene > [6]arene > [4]arene. In all cases, the complexation process is primarily enthalpy driven. The favorable enthalpic contribution for extraction of Pb2+ is in the order hexamer ≈ monomer > tetramer > pentamer. However, the unfavorable entropic loss follows the order: monomer > hexamer > tetramer > pentamer. Overall stability of the host-guest complex is the function of entropy-enthalpy compensation and the free energy of complexation is minimum for the pentamer, followed by tetramer ≈ hexamer and monomer. Although the carboxylic acid derivative of calix[4]arene is more preorganized than the calix[5]arene derivative, extraction of Pb2+ ion with the tetramer passes through greater entropic loss than that with the pentamer and the degree of preorganization of calix[4]arene derivative is far from perfect for the complexation and extraction of Pb2+ ion. As compared to tetrameric and hexameric counterparts, the structural features of the carboxylic acid derivative of calix[5]arene prior to complexation contribute much to interact with the Pb2+ ion and form a thermodynamically stable complex. Supplementary materials are available for this article. Go to the publisher's online edition of Solvent Extraction and Ion Exchange to view the supplemental file. 相似文献
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杯芳烃作为超分子化学的重要组成部分,近年来得到了快速发展并成为化学家的研究热点。以脱叔丁基-杯[4]芳烃为原料合成了杯[4]芳烃偶氮衍生物,其结构经IR和1H NMR所表征。研究了该主体分子对金属离子的萃取性能,实验结果表明,该主体分子对Mg2+具有较高的萃取作用。讨论了主客体间配位作用的机制。 相似文献
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杯芳烃/聚丙烯共混体系耐热氧性能的研究 总被引:2,自引:0,他引:2
合成了对叔丁基杯[4]、杯[6]、杯[8]芳烃,并用热重法和烘箱老化评价了共混体系的耐热氧性能。结果表明,杯芳烃能明显提高聚丙烯的耐热氧性能,其耐热氧能力为:对叔丁基杯[6]芳烃>对叔丁基杯[4]<2,6-二叔丁基-4-甲基苯酚。 相似文献
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Ömer Güngör 《分离科学与技术》2018,53(6):896-902
This paper presents a study on the removal of azo dyes [Methyl Orange (MO) and Trapaeolin 000 (TP)] from aqueous solution using new phthalonitrile and isoindoline substituted calix[n]arene derivatives into the organic phase in order to explore the potential use of these calixarenes as low-cost efficient extractants for removal of these azo dyes from wastewater. The effect of NaCl concentration, contact time, and pH on the extraction of these azo dyes was also investigated for all calixarene derivatives. The stoichiometric ratio between the calixarene derivatives (5 and 6) and selected azo dyes (MO and TP) was estimated through job’s plot. 相似文献
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Bernd Garska Monir Tabatabai Urs Fischer Norbert Moszner Andreas Utterodt Helmut Ritter 《Polymer International》2012,61(7):1061-1066
We describe the synthesis of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐dioxypropylphosphonic acid‐26,28‐dimethacryloyloxy‐calix [4]arene and 5,11,17,23‐tetra‐tert‐butyl‐25‐oxypropylphosphonic acid‐27‐hydroxy‐26,28‐dimethacryloyloxy‐calix[4]arene starting from para‐tert‐butyl‐calix[4]arene. The complete reaction was proved by matrix‐assisted laser desorption ionization time of flight mass spectrometry and nuclear magnetic resonance spectroscopy. The influence of these compounds on the kinetics of the radical polymerization of methyl methacrylate was shown by dilatometry. Furthermore, the adhesive properties of dental adhesives containing these calix[4]arene derivatives were investigated. Copyright © 2012 Society of Chemical Industry 相似文献
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以杯[4]芳烃为起始原料,首先制得中间体杯[4]芳烃双溴代烷基衍生物,然后经微波辐射和阴离子交换,共得9种杯[4]芳烃咪唑盐衍生物,化合物的结构与构象经元素分析、IR、1HNMR、19FNMR、31PNMR表征.研究了它们在对氯硝基苯氟化反应中的催化性能以及对K+的萃取性能.结果表明,这9种化合物在氟化反应中的催化效果良好,对氟硝基苯的收率为80.89%~92.67%;同时化合物对K+具有较好的萃取效果,其中以化合物25,27-二[4-(3-甲基咪唑)乙氧基]-26,28-二羟基-5,11,17,23-四叔丁基杯[4]芳烃六氟磷酸盐的萃取效果最好,萃取率可达75.45%. 相似文献
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《分离科学与技术》2012,47(5):664-672
In the present article a comparative extraction efficiency of dichromate by a calix[4]arene derivative (d) and a newly synthesized calix[4]arene appended Amberlite XAD-4 resin (5) are reported. The liquid and solid phase extraction methods have been applied to ascertain the extraction efficiency of both the calix[4]arene derivative and the resin. Different parameters have been optimized such as pH, dosage, concentration, and temperature. Analysis of experimental data has been carried out by log-log plot analyses and the determination of characteristic parameters of each isotherm model such as Freundlich, Langmuir, and Dubinin-Radushkevich (D-R). The kinetic adsorption experiments show that the adsorption process follows pseudo second order kinetics. The adsorption mechanism has been investigated by Reichenberg (R-B) and Morris-Webster equations. From the thermodynamic parameters it is concluded that the adsorption process is endothermic and spontaneous in nature at higher temperature. The results show that the resin-5 has good capability to efficiently remove dichromate from aqueous media. 相似文献
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以对叔丁基苯酚、甲醛为主要原料合成杯芳烃母体对叔丁基杯[n]芳烃(n=4,6,8);以1,3-丙烷磺内酯、1,4-丁烷磺内酯为醚化试剂,经Williamson醚化反应,合成出6种杯芳烃基低聚表面活性剂。利用IR表征了中间体和最终产物的结构,确定了化合物的结构与所设计的分子结构相同。用染料法对所合成产物进行了定性鉴定,并用滴体积法测定了表面活性剂水溶液25℃时的表面张力。结果表明,随着杯芳烃空腔的逐渐增大,cmc值降低,γcmc值升高,Γcmc值下降,Am值升高。 相似文献
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Four different mercaptoalkyl-substituted calixarene derivatives (5,11,17,23-tetra-tert-butyl-25,27-bis(3-mercaptopropoxyl)-26,28-dihydroxycalix[4]arene, 25,27-bis(3-mercaptopropoxyl)-26,28-dihydroxycalix[4]arene, 25,27-bis(5-mercaptopentanoxyl)-26,28-dihydroxycalix[4]arene and 5,17-di-tert-butyl-11,23-di-carboxyl-26,28-bis(3-mercaptopropoxyl)-25,27-di-hydroxycalix[4]arene) were synthesized. Their structures were characterized by Fourier transform infrared spectroscopy (FTIR), 1H and 13C NMR spectroscopy, and elemental analysis techniques. Moreover, their extraction capabilities at different parameters such as pH, shaking speed, and shaking time were examined toward dichromate ions. Results implied that all mercaptoalkyl-substituted calixarene derivatives showed an extraction capability toward dichromate anion while the carboxyl-functionalized calixarene-marcapto-alkyl derivative exhibited the highest extraction capability. 相似文献
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《Journal of Supramolecular Chemistry》2002,2(6):515-519
Single crystals of two calix[4]arene derivatives, that is, 5,11,17,23-tetra-tert-butyl- 25,27-bis[2-[N-(3-methoxy-4-methoxy-benzylidene)-amino]ethoxy]-26,28- dihydroxy calix[4]arene (1) and 5,11,17,23-tetra-tert-butyl-25,27-bis[2-[3- pyridine carbonyl-amino]ethoxy]-26,28-dihydroxy calix[4]arene (2), were prepared and their crystal structures have been determined by X-ray crystallographic study. As compared with calix[4]arene derivative 1 possessing CN functional group, compound 2 bearing the NH group could form not only intermolecular hydrogen bonds between the hydrogen atom in NH group and the oxygen atom in CO of an adjacent calix[4]arene molecule, but also intramolecular hydrogen bonds between the N—H⋯OC moieties in solid state, giving a rare linear molecular aggregation. 相似文献
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Hongxia Chen Feng Liu Fangjie Qi Kwangnak Koh Keming Wang 《International journal of molecular sciences》2014,15(4):5496-5507
Three calix[4]arene (Cal-4) derivatives which separately contain ethylester (1), carboxylic acid (2), and crownether (3) at the lower rim with a common reactive thiol at the upper rim were synthesized and constructed to self-assembled monolayers (SAMs) on Au films. After spectroscopic characterization of the monolayers, surface coverage and orientation of antibody immobilized on the Cal-4 derivative SAMs were studied by surface plasmon resonance (SPR) technique. Experimental results revealed that the antibody could be immobilized on the Cal-4 derivatives spontaneously. The orientation of absorbed antibody on the Cal-4 derivative SAMs is related to the SAM’s dipole moment. The possible orientations of the antibody immobilized on the Cal-4 derivative 1 SAM are lying-on or side-on, while on the Cal-4 derivative 2 and Cal-4 derivative 3 head-on and end-on respectively. These experimental results demonstrate the surface dipole moment of Cal-4 derivative appears to be an important factor to antibody orientation. Cal-4 derivatives are useful in developing site direct protein chips. 相似文献
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Polyaniline (PANI) molecular composites were synthesized by chemical oxidative polymerization of the aniline and aniline dimer, N‐phenyl‐1,4‐phenylendiamine, in the presence of a macrocycle, calix[8]arene p‐octasulfonic acid (C8S), using ammonium peroxidisulfate as oxidant. The macrocycle has acted both as acid dopant and surfactant to obtain processable PANI‐ES. The PANI/calix[8]arene p‐octasulfonic acid composite was also obtained by a simple doping of PANI emeraldine base form with calix[8]arene sulfonic acid. The structure of materials was confirmed by Fourier transform infrared, UV–vis and nuclear magnetic resonance spectroscopy. All synthesized composite materials are amorphous and soluble in chloroform, dimethylsulfoxide, NMP, showing excellent solution‐processing properties combined with electrical conductivity. Cyclic voltammetry evidenced a good electroactivity for the composite films. Dielectric properties (dielectric constant and dielectric losses) were determined and are comparable with those of other PANI/ionic acid polymer composites. Preliminary studies have evidenced a high dielectric constant (104 at 100 Hz) and electrical conductivity of 6 × 10?3 S/cm for PANI composites. From sulfur elemental analysis of the PANI/calixarene, it results that the content in macrocycle is ~30% (weight). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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This article describes the synthesis and characterization of four new calix[4]arene ionophores 5–7 and 9 and corresponding two new silica gel‐immobilized calix[4]arene ionophores containing pyridine 10 and 11 via modification of calix[4]arene monoamide derivatives 5 and 6 with aminopropyl silica gel, respectively. The extraction studies have been performed using liquid–liquid extraction for receptors 5–7 and 9 and solid–liquid batchwise sorption procedures for receptors 10 and 11 . Obtained extraction results showed that the immobilized‐calix[4] arene ionophores 10 and 11 have high extraction ability toward chromate and phosphate anions as compared to their corresponding monomeric precursors 5 and 6 . © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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Hongyu Guo Fafu Yang Xianfeng Chai Ziyu Jiao Congcong Li 《Iranian Polymer Journal》2012,21(7):451-456
By introducing four ester groups on p-tert-butylcalix[6]-1,4-crown-4 and then ammonolysis with ethanolamine, p-tert-butylcalix[6]-1,4-crown-4 amido derivative with four terminal hydroxyl groups (4) was obtained in good yield. Further by reacting compound 4 with 1,1,1-tris(tosylatemethyl)propane (6) in NaH/THF system, the novel netty calix[6]-1,4-crown-based polymer 7 was prepared in ??4+3?? condensation mode. The structure of polymer 7 was confirmed by elemental analysis, IR and 1H NMR spectra. The loose pores and cross-linked netty architecture were observed for polymer 7 in its SEM images. The M n of polymer 7 was 39,816 which indicated an average of approximately 23 calixarene units in each polymer molecule. Polymer 7 exhibited outstanding adsorption abilities for series of aniline derivatives (aniline, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, o-nitroaniline, m-nitroaniline and p-nitroaniline). The adsorption percentages for these aniline derivatives were above 90?%. The saturation adsorption capacities for aniline and p-nitroaniline were as high as 2.30 and 2.22?mmol/g, respectively. The adsorption abilities of polymer 7 kept stable at pH 6?C10 and it could be re-used after desorption of 10?% HCl. The high adsorption abilities of polymer 7 for aniline derivatives were not just because of ?ШC?? stack action of the phenyl groups and the hydrogen bond action, but also due to the stable conformation of calix[6]arene skeleton and big cavity, which were favorable for adsorption of aniline derivatives. 相似文献
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Copolyethers and polyurethanes containing lower and upper rim calix[4]arene units in the fixed cone conformation were prepared in good yield by polycondensation reactions of distal calix[4]arene diols with bisphenol-A/dibromomethane and 2,4-tolylendiisocyanate (TDI), respectively. In a similar way were prepared calix[4]arene-crown-5 and -crown-6 polyurethanes in the fixed 1,3-alternate conformation by condensation of TDI with lower rim calixcrown-5 and calixcrown-6 diols. However, the poor solubility in common organic solvents of the copolyether derivatives (Mw=11,100-11,600 g/mol) hampered further studies on their ionophoric properties. Aiming to obtain model compounds for the investigation of both extraction abilities and ionophoric properties of the polyurethane materials, several bis-urethanes were also synthesized by reaction of the calix[4]arene diols with p-tolylisocyanate (TI). The extraction ability measurements of monomeric and polymeric calix[4]arene urethanes (Mw=12,300-83,500 g/mol) towards alkali metal cations (Li+, Na+, K+, Rb+, Cs+) and Ag+showed a remarkable efficiency and selectivity of calixcrown-6 polyurethane toward Rb+, Cs+and Ag+. 相似文献