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1.
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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Calix[4]arene amide derivatives were employed as new additives within the sol-gel encapsulation of lipase from Candida rugosa (CRL) to improve its catalytic properties. Evaluation of catalytic activity of the encapsulated lipases was acheived by enantioselective hydrolysis of both racemates, Naproxen methyl ester and 2-phenoxypropionic acid methyl ester, in aqueous buffer solution/isooctane reaction system. Results show that enantioselectivity was improved by using calix[4]arene amide derivatives-based encapsulated lipases. The reaction of naproxen methyl ester resulted in 47.6% conversion (x) in 24 h with 88.9% enantiomeric excess of substrate (ees), analogous to an enantioselectivity (E) value of 297 (E = 137 for the encapsulated free enzyme). The conversion of 2-phenoxypropionic acid methyl ester, obtained was 48.4% with E value of 327, enantiomeric excess of substrate (ees) of 92% for the reaction time of 1 h (E = 211 for the encapsulated free enzyme). 相似文献
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Naoya Morohashi Ryoichiro Naito Nobuhiko Iki Sotaro Miyano 《Israel journal of chemistry》2001,41(4):303-308
A new synthetic strategy for the construction of an inherently chiral, sulfur-bridged calix[4]arene molecular framework was presented by oxidation of one of the four epithio bonds of a tetrathiacalix[4]arene derivative of 1,3-alternate conformation: Tetra(carboxymethyl) ether of p-tert-butyltetrathiacalix[4]arene of 1,3-alternate conformation ( 7 ) was converted to the tetra(l-menthoxycarbonylmethyl) ether ( 8 ). Oxidation of the tetra l-menthyl ester 8 by treatment with NaBO3 (1.1 molar equiv.) afforded a pair of diastereomers of the monosulfinyl derivatives ( 9 ) in 58% yield, which were readily separable by silica-gel column chromatography. Removal of the l-menthyl moieties followed by methyl esterification gave enantiomerically pure samples of inherently chiral (-)- and (+)-monosulfinyltrithiacalix[4]arene derivatives ((-) -10 and (+) -10 ) in 62 and 56% yield, respectively. 相似文献
4.
A macroporous silica‐based 1,3‐[(2,4‐diethyl‐heptylethoxy)oxy]‐2,4‐crown‐6‐calix[4]arene (Calix[4]arene‐R14) supramolecular recognition polymeric composite, (Calix[4]+Oct)/SiO2‐P, was synthesized. It was performed by impregnating and immobilizing Calix[4]arene‐R14 and n‐octanol into the pores of the macroporous SiO2‐P particles support. n‐Octanol was used to modify Calix[4]arene‐R14 through hydrogen bonding. The effect of eight typical fission products contained in highly active liquid waste (HLW) on the adsorption of Cs(I), one of the heat generators, was investigated at 298 K by examining the effect of contact time and the HNO3 concentration in a range of 0.3–7.0 M. (Calix[4]+Oct)/SiO2‐P showed excellent adsorption ability and high selectivity for Cs(I) at 4.0 M HNO3 over the tested elements. The partitioning of Cs(I) from a simulated HLW was operated by (Calix[4]+Oct)/SiO2‐P packed column. Cs(I) was able to be effectively eluted by water and separated from the tested metals. It is demonstrated that (Calix[4]+Oct)/SiO2‐P is promising to apply in chromatographic separation of Cs(I) from HLW. © 2010 American Institute of Chemical Engineers AIChE J, 2010 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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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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Tatsuya Oshima Ryota Saisho Kaoru Ohe Yoshinari Baba Keisuke Ohto 《Reactive and Functional Polymers》2009,69(2):105-110
Macrocyclic host molecules calixarene carboxylic acid derivatives are found to act as powerful extractants for biologically important amino compounds. A series of adsorbents were prepared from a methacrylate-based polymer Amberlite XAD-7 by impregnation with various calixarene derivatives, for adsorptive recovery of amino acid derivatives. The larger macrocycles calix[6]arene and calix[8]arene carboxylic acid derivatives were more effective for adsorption of amino acid derivatives on the impregnated resin than the calix[4]arene derivative. Since adsorption proceeds mainly via electrostatic interaction, the carboxylic acid groups introduced into the calixarene platform were important for adsorption of cationic amino acid derivatives. The adsorption selectivity for amino compounds using adsorbent impregnated with the calix[6]arene carboxylic acid derivative depends simply on the hydrophobicity of the adsorbates. 相似文献
9.
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
10.
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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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
13.
P. Amruta Reddy Ram P. Kashyap William H. Watson C. David Gutsche 《Israel journal of chemistry》1992,32(1):89-96
Chlorine dioxide and thallium trifluoroacetate are shown to be useful reagents for the preparation of calixquinones. p-H-Calix[4]arene( 1a ),p-H-calix[5]arene ( 1b ), and p-H-calix[6]arene ( 1c ) are oxidized in modest yields by ClO2 to the fully quinonoid compounds calix[4]tetraquinone ( 2a ), calix[5]pentaquinone ( 2b ), and calix[6]hexaquinone ( 2c ), respectively. Although Tl(OCOF3)3 is less effective for the oxidation of 1a-c , it proves to be the reagent of choice for converting partially etherified or esterified calixarenes carrying p-tert-butyl groups directly to partially quinonoid calixarenes. Thus, monosubstituted calix[4]arenes yield triquinones; disubstituted calix[4]arenes yield diquinones; trisubstituted calix[4]arenes yield monquinones; and tetrasubstituted calix[6]arenes yield diquinones. The structures of the calixquinones have been established by elemental analysis, 1H NMR spectroscopy, mass spectroscopy, and in the case of 2c by X-ray crystallography. Since the starting materials are readily accessible, the calixquinones become easily available compounds for further study. 相似文献
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Monir Tabatabai Bernd Garska Norbert Moszner Andreas Utterodt Helmut Ritter 《Polymer International》2011,60(7):995-1000
The synthesis of a functionalized calix[4]arene bearing 1,3‐dipolaric nitrone groups ( 5 ) has been carried out. The reaction of N‐methylhydroxylamine or N‐propylhydroxylamine with the carbonyl group of 5,11,7,23‐tetraformyl‐25,26,27,28‐tetraalkoxycalix[4]arene leads to calix[4]arenes bearing a nitrone function at each of the four para‐positions. Via 1,3‐dipolar cyclo‐addition of acrylic acid methyl ester with the nitrone functions of 5 , subsequently an upper rim‐substituted tetraisoxalidinecalix[4]arene is quantitatively synthesized. Further, the minimization of shrinkage of a dental filling depending on the amount of calix[4]arene‐tetranitrone is discussed. Copyright © 2011 Society of Chemical Industry 相似文献
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《分离科学与技术》2012,47(17):2395-2402
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
18.
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
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In this study, a convenient method for the synthesis of thirteen novel disazo dyes containing 25,26,27‐tribenzoyloxy‐28‐hydroxycalix[4]arene have been described. 5,11,17,23‐Tetra‐tert‐butyl‐25,26,27,28‐tetrahydroxycalix[4]arene, 25,26,27,28‐tetrahydroxycalix[4]arene and 25,26,27‐tribenzoyloxy‐28‐hydroxycalix[4]arene were synthesised based on previously published literature. 2‐Arylhdrazone‐3‐ketiminobutyronitriles were synthesised and reacted with hydrazine hydrate to afford the corresponding 5‐amino‐4‐arylazo‐3‐methyl‐1H‐pyrazoles. Thirteen novel hetaryldisazocalix[4]arene derivatives were achieved by diazotisation of 5‐amino‐4‐arylazo‐3‐methyl‐1H‐pyrazoles using nitrosylsulphuric acid, coupled with 25,26,27‐tribenzoyloxy‐28‐hydroxycalix[4]arene. The obtained hetaryldisazocalix[4]arene dyes were characterised based on Fourier Transform–infrared, proton nuclear magnetic resonance and mass spectroscopic techniques, as well as elemental analysis. The solvatochromic behaviour of these dyes in various solvents was examined. Acid‐base effects on the visible absorption maxima of the dyes were also reported. 相似文献