The synthesis of the cone conformers of 5,11,17,23-tetra-tert-butyl-25,27-bis[(4-nitrobenzyloxy)-26,28-dihydroxy]-calix[4]-arene (2), 5,11,17,23-tetra-tert-butyl-25,27-bis[(4-nitrobenzyloxy)]calix[4]arene-crown-6 (3) and 5,11,17,23-tetra-tert-butyl-25,27-bis[(4-aminobenzyloxy)]calix[4]arene-crown-6 (4) containing polymerizable side arms, along with their oligomeric analogue 5, is reported. Extraction studies with monomers 3 and 4 and the oligomer 5 show no difference in their extraction behavior and selectivity, whereas, ionophore 2 is a poor extractant for alkali metal cations. These observations suggest that, substitution of side arms on the lower rim of calix moiety can enhance the calix[4]-crown-6 cone conformers function to extract alkali metal cations in two phase extraction systems. 相似文献
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
Two new polymers containing pendant calix[4]arene units with nitrile functionalities at their lower rim have been synthesized via radical initiated reactions involving a vinylic monomer 6 {5,11,17,23-tetra-tert-butyl-25,26,27-tris(cyanomethoxy)-28-(2-acryloyloxy) ethoxycalix[4]arene} and with styrene. A five atom spacer group was incorporated between the bulky calixarene core and the acrylate moiety in order to minimize steric interactions which proved to impede the polymerization. The complexation studies were made by using liquid–liquid extraction procedures. It has been deduced from the observations that both polymers show a good selectivity towards Hg2+ like their precursor 5,11,17,23-tetra-tert-butyl-25,26,27-tricyanomethoxy-28-(2-hydroxy)ethoxycalix[4]arene 5, which supports their utility as adsorbents or potential candidate materials for fabricating membranes and sensors, which can separate or detect Hg2+ metal ions in a high selectivity. 相似文献
In this article, calix[4]arene (4) was prepared by debutylation and hydrolyses reacting from 25,27-dibenzoyl-26,28-dihydroxy-5,11,17,23-tetra(tert-butyl)calix[4]arene (2). Azocalix[4]arenes (6a-c) were coupled by linking 4-methoxy, 4-ethyl, and 4-nitroaniline to calix[4]arene (4) through a diazo-coupling reaction. Thermal behavior characteristics and decomposition routes of 25,26,27,28-tetrahydroxy-11,23-di(tert-butyl)-5,17-(p-substitue phenyl)azocalix[4]arene (6a-c) were investigated in air atmosphere by means of thermogravimetry (TG), differential thermogravimetry (DTG), and differential thermal analysis (DTA) analyses. It was found that the decomposition of all compounds complete with two exothermic stages which corresponded to removal of substitute groups (methoxy-, ethyl-, nitro-) and second stage rest of structure decomposition. 相似文献
In the environment, the presence of toxic oxyanions such as Cr(VI) and As(V), especially in drinking water, creates serious hazards to human health. For efficient and selective detection of these species; novel calix[4]arene-based thiourea derivatives which obtained using p-tert-butylcalix[4]arene as starting material have been prepared from m-aniline or o-aniline or o-aminophenol in moderate yield. The structures of all new synthesized compounds obtained from these reactions were determined by using FTIR, 1H, and 13C NMR spectroscopy. The complexing properties of calix[4]arene-based thiourea derivatives have been studied towards the As(V) and Cr(VI). It was found that calix[4]arene-based thiourea derivative 5,11,17,23-tetra-tert-butyl-25,27-bis(o-amino-phenylthioureido propoxy)-26,28-hydroxycalix[4]arene is an effective extractant for carrying HCr2O72? anions. 相似文献
This article describes a convenient method for the synthesis of two new polymeric resins via nucleophilic substitution reactions involving 5,11,17,23-tetrakis[(propylthio)methyl]-25,26,27,28-tetrahydroxycalix[4]arene 4, and 5,11,17,23-tetrakis[(methylthio)methyl]-25,26,27,28-tetrahydroxycalix[4]arene 6, as precursors with Merrifield's resin. The extraction studies were made using both liquid-liquid extraction and solid-liquid batchwise sorption procedures. The calix[4]arene based polymeric resins have high extraction ability toward metal cations and Na2Cr2O7 as compared to their monomeric precursors. 相似文献
In this study, transfer reactions of alkali and alkaline-earth metal ions across a micro-water/1,2-dichloroethane (1,2-DCE) interface facilitated by a novel calix[4]arene derivative, 5,11,17,23-tetra-tert-butyl-25,27-bis(2′amino-methylpyridine)-26,28-dihydroxy calix[4]arene (APHC4), were investigated by cyclic and differential pulse voltammetry techniques. Well-defined voltammetric behavior was obtained only for K+ ion among the used metal ions. The electrochemical data were used to determine the stoichiometry and the appropriate association constant of the occurring complex between K+ ion and APHC4. The obtained steady-state voltammograms indicated that the facilitated transfer process occurs with a TIC/TID mechanism according to 1:1 stoichiometry. The logarithm of the association constant () of K(APHC4)+ complex in the DCE phase was calculated to be 6.32. Also, the availability of the facilitated transfer for the design of an amperometric screening sensor for K+ ion was evaluated in the range of 50–500 μmol dm−3. 相似文献
Abstract The selective liquid-liquid extraction of Fe3+ cation from the aqueous phase to the organic phase was carried out by using p-tert-butylcalix[4]arene [L1], ca-lix[4]arene [L2], p-nitro-calix[4]arene [L3], calix[4]arene p-sulfonic acid [L4], p-(diethylamino)methylcalixt4]arene [L5], tetramethyl-p-tert-butylcalix[4]arene tet-raketone [L6], 25,27-dimethyl-26,28-dihydroxy-p-tert-butylcalix[4]arene diketone [L7], calix[4]arene-bearing dioxime group on the lower rim [L8], and a monooxime [L9]. The effect of varying pH upon the extraction ability of calixarenes substituted with electron-donating and electron-withdrawing groups at their p-position was examined. Observed results were compared with those found for unsubstituted calix[4]arene. 相似文献
The synthesis and characterization of novel magnesium porphyrazine, peripherally symmetrically derived from 1,3-alternate 26,28-[35,36-dicyano-34,37-dithia-29,32,40,43-tetraoxa-35-en]calix[4]arene-crown-5, were carried out. This compound was prepared starting from cis-1,2-dicyano-1,2-ethylenedithiolate and 1,3-alternate 26,28-bis(5′-chloro-3′-oxapentyloxy)calix[4]arene-crown-5. The new macrocycle was characterized using the techniques of UV–vis, 1H, 13C NMR, IR, MS and elemental analysis. 相似文献
ABSTRACT The extraction properties of cone-5,11,17,23-tetra-t-butyl-25,26,27,28-tetrakis(diphenylphosphinoylmethoxy)calix[4]arene (1) in 1,2-dichloroethane towards rare-earth metal ions at 25 °C have been investigated. The slope analysis showed a 1:1 metal/ligand ratio for the extracted species (La, Eu, Er and Y). The distribution coefficients increase with the polarity of the diluents : chloroform ≤ dichioromethane ≤ 1,2-dichloroethane ≤ nitrobenzene. In the competitive extraction of 11 rare-earth metal ions (La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb and Y), ligand 1 exhibits higher extraction efficiency and a better separation factor than tri-n-octylphosphine oxide. 相似文献
ABSTRACT The extractive properties of the cone and partial-cone isomers of 5,11,17,23-tetra-?ert-butyl-25,27-bis( diethylcarbamoylmethoxy)-26,28-bisi( diphenylphospninoylmethoxy) calyx[ 4] arene ( cone-1 and partial-cone -1) in 1,2-dichloroethane towards rare-earth metal ions in nitrate media at 25 ° C were investigated. The analysis of the extraction equilibrium obtained from a mixture of four rare-earths ( La, Eu, Er and Y) revealed that the extracted species have a 1 1 metal/ ligand ratio for both ligands. The intra-group separation efficiercies of the ligandls have been evaluated in a competitive extraction process of 11 rare-earth metal ions ( La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb and Y). Significantly higher extractive properties were found for cone-1 with respect to partial-cone-1, suggesting the crucial role of the phosphoryl groups in the complexation of the rare-earth ions. These findings were 相似文献
The synthesis of 5,11,17,23‐amino‐25,26,27,28‐propoxycalix[4]arene (calix[4]amine, 4 ) starting from 5,11,17,23‐nitro‐25,26,27,28‐propoxy‐calix[4]arene ( 3 ) via microwave‐assisted transfer hydrogenation is reported. Furthermore, the calix[4]amine ( 4 ) is functionalized with an acrylamide moiety. The swelling behavior in water, the influence on the glass transition temperature, and the shear modulus of a crosslinked N,N‐dimethylacrylamide (NDA) polymer with 5,11,17,23‐acrylamido‐25,26,27,28‐propoxycalix[4]arene ( 5 ) and EGDMA, respectively, are investigated.
Extraction of microamounts of radioactive cesium and strontium by 25,27-bis(1-octyloxy)calix[4]-26,28-crown-6 (DOC[4]C6) and dicyclohexyl-18-crown-6 (DCH18C6) from nitric acidic solutions into alcohols, ketones and some other solvents was studied. We concentrated on collecting detailed data possibly useful for subsequent evaluations of appropriate schemes and mechanisms. Although not testing in fullness the system with DOC[4]C6 and DCH18C6 in 1-octanol, we present some evidence of its suitability such as fast kinetics, chemical and radiation stability, and invariance of parameters (process stability) after several times repeated batch extraction-strip cycles. Some peculiarities of a possible mechanism of extraction in these systems are reported. 相似文献