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1.
Structure and conformational equilibrium of thiacalix[4]arene by density functional theory 总被引:2,自引:0,他引:2
Density functional theory calculations for the structure and conformational equilibrium of thiacalix[4]arene are reported. The conformational equilibrium of thiacalix[4]arene, a heterocalixarene in which the phenol groups are bridged by sulphur atoms is compared to the conformational equilibrium of calix[4]arene. Thiacalix[4]arene conformational energies relative to the cone conformer (ΔE's) are reduced in comparison with calix[4]arene. This conformational change is in qualitative agreement with recent NMR spectroscopy measurements of the conformational equilibrium for a tetraethylether of thiacalix[4]arene in a CDCl3 solution which indicates an enhanced chemical exchange of thiacalixarene conformers in comparison with similar methylene bridged structures. Density functional theory results for the structure of thiacalix[4]arene are in good agreement with recent X-ray diffraction measurements. The electrostatic potentials in the cone conformers of thiacalix[4]arene and calix[4]arene suggest that their complexation or recognition abilities can be significantly different. Dipole moments of the four thiacalix[4]arene conformers are in the order: cone>1,2-alternate>partial-cone>1,3-alternate. 相似文献
2.
Meriem Lamouchi Erwann JeanneauJérémy Coulm Arnaud BrioudeCédric Desroches 《Comptes Rendus Chimie》2013,16(12):1073-1078
A simple method for thiacalix[4]arene O-monoamide preparation with high yields using 5,11,17,23-tetra-tert-butyl-28-(ethoxycarbonyl)methoxy-2,8,14,20-tetrathiacalix[4]arene reaction with diaminoalkanes is reported. The solid state cyclization reaction of the acylethylenediamines function of 5,11,17,23-tetra-tert-butyl-28-O-[(N-(2-aminoethyl)aminocarbonyl)-methoxy]thiacalix[4]arene leading to the formation of the 5,11,17,23-tetra-tert-butyl-28-[2-methoxy-imdazoline]thiacalix[4]arene compound is described for the first time for the calixarene macrocycle family. Finally, preliminary results show that O-mono-amide-thiacalixarene derivatives are promising candidates for the production of self-assembled materials and efficient precursors for the synthesis of bisthiacalix[4] arenes. 相似文献
3.
Qianling Guo Wenxiang Zhu Shujing Dong Shulan Ma Xi Yan 《Journal of Molecular Structure》2003,650(1-3):159-164
The title calixarene, dimanganese thiacalix[4]arene tetrasulfonate, was prepared and its crystal structure was determined. [Mn(H2O)6]2[thiacalix[4]arene tetrasulfonate]·0.5H2O crystallizes in the monoclinic system, P2(1)/m space group, with a=13.014 (6), b=14.146 (9), c=13.184 (7) Å, β=113.307 (10)°, V=2229 (2) Å3 and Dc=1.710 gcm−3, Z=2. The title calixarene exists in the solid state as bilayer structure. The hydrophobic organic layer consists of thiacalix[4]arene tetrasulfonate in an up-down fashion, whereas, the hydrophilic inorganic layer consists of hexaaquamanganese (II) which is linked to the former through a second-sphere coordination. 相似文献
4.
Nanocomposites of polyaniline(PANI) and the macrocycle thiacalix[4]arene tetra sulfonate(TCAS) were successfully synthesized in feed ratios of 1:0.25, 1:0.50 and 1:0.75 by three prevail synthetic methods, i.e. in situ polymerization, emulsion polymerization and solution casting technique. The structures of the nanocomposites were confirmed by FTIR, UV-Vis, XRD, SEM, and TEM techniques. The conductivity was measured by a four probe method. The conductivity was recorded to be as high as 105 × 10 2S cm 1for the nanocomposite with a nanometer size structure and homogeneously distributed morphology. The electroactivity of the nanocomposites was approved by cyclic voltammetry(CV) and impedance spectroscopy technique(EIS). The antioxidant ability and thermal property of the composites were further studied. Preliminary studies have evidenced the production of conductive nanocomposites with good thermal property and relatively good solubility in N-methyl 2-pyrrolidone(NMP), with the antioxidant activity reaching up to 80%. 相似文献
5.
We have synthesized a ferrocene-based 1,3-alternate thiacalix[4]arene ditopic receptor 3 that contains four identical polyether arms terminated with the ferrocene amide moieties. Our studies have revealed that this redox-active receptor can be used as an electrochemical sensor to recognize both europium (Eu3+) and dihydrogen phosphate ions with a high selectivity. 相似文献
6.
New fluorescent chemosensors 1,3-alternate-1 and 2 with pyrenyl-appended triazole-based on thiacalix[4]arene were synthesized. The fluorescence spectra changes suggested that chemosensors 1 and 2 are highly selective for Ag+ over other metal ions by enhancing the monomer emission of pyrene in neutral solution. However, other heavy metal ions, such as Cu2+, and Hg2+ quench both the monomer and excimer emission of pyrene acutely. The 1H NMR results indicated that Ag+ can be selectively recognized by the triazole moieties on the receptors 1 and 2 together with the ionophoricity cavity formed by the two inverted benzene rings and sulfur atoms of the thiacalix[4]arene. 相似文献
7.
A novel mononuclear complex of p-sulfonatecalix[4]arene and neodymium (III) ions in the presence of pyridine N-oxide has been investigated by X-ray diffraction study, which reveal that the bi-layer sheet structure is formed in the solid state. An aquated neodymium ion connects the adjacent calixarene-pyridine N-oxide complex units through multiple hydrogen bonds to stabilize the bi-layer structure. 相似文献
8.
A convenient procedure for direct introduction of one formyl group into p-tert-butylcalix[4]arenes through ipso substitution is described. 相似文献
9.
The bis(calix [4] arene)3 was synthesized in moderate yield by the reaction of p-tert-butylcalix [4] arene (1) with 1,4-bis(chloromethyl) benzene (2). The conformation of all alkylated product 4 was investigated by the variable-temperature ^1H-NMR. 相似文献
10.
Abdelhalim Guelzim Mohamed Saadioui Zouhair Asfari Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(1-2):91-95
The synthesis of25-[2-(ethoxy-1-p-toluene-sulfonate)phenyl]-26,27,28-trihydroxy calix[4]arene3 as a byproduct of the preparation of 1,3-dialkylated25,27-di-[2-(ethoxy-1p-toluene-sulfonate)phenyl]-26,28-dihydroxy calix[4]arene 2 is reported. Compound 3 is a monoalkylatedcalix[4]arene in the cone conformation. The X-ray structure of 3 showed that this conformation is stabilized by intramolecular hydrogen bonding. 相似文献
11.
A. Suwattanamala D. Appelhans M. Wenzel K. Gloe A.L. Magalhes J.A.N.F. Gomes 《Chemical physics》2006,320(2-3):193-206
A comparative study on Zn2+ and Cu2+ complexes of the novel compound 5,11,17,23-tetra-tert-butyl-25,27-bis{[4-(methoxycarbonyl)phenyl]methoxy}-2,8,14,20-tetrathiacalix[4]arene, that possesses potential as a core unit for the construction of molecular receptors, is presented using semiempirical AM1 calculation. The possible structures of each metal complex and their corresponding energetic data are compared with the parent 5,11,17,23-tetra-tert-butyl-2,8,14,20-tetrathiacalix[4]arene. The complexation ability of both thiacalix[4]arenes towards the two metal ions is discussed on the basis of binding energies. Both thiacalix[4]arene 1:1 complexes show higher complexation ability towards Cu2+. However, 5,11,17,23-tetra-tert-butyl-25,27-bis{[4-(methoxycarbonyl)phenyl]methoxy}-2,8,14,20-tetrathiacalix[4]arene presents lower complexation ability when compared with the 5,11,17,23-tetra-tert-butyl-2,8,14,20-tetrathiacalix[4]arene. The results of liquid–liquid extraction experiments of the thiacalix[4]arenes are in good agreement with the theoretical calculations. 相似文献
12.
Asiya Mustafina Margit Gruner Aidar Gubaidullin Sergey Katsyuba Viktoriya Skripacheva Elena Zvereva 《Supramolecular chemistry》2013,25(4):203-211
The 1H NMR and X-ray analysis data reveal the guest-induced cone → partial cone and cone → 1,2-alternate conformational shift in aqueous methanol solutions and solid state for a p-sulphonatothiacalix[4]arene-[Zn(dipy)3]2+ host–guest system. The experimental data, together with DFT calculations, show that the guest-induced conformational shift of p-sulphonatothiacalix[4]arene is facilitated by the deprotonation of phenolic groups. 相似文献
13.
Yu Liu 《Tetrahedron》2003,59(40):7967-7972
A series of novel double-armed calix[4]arene derivatives, i.e. 5,11,17,23-tetra-tert-butyl -25,27-bis[2-[(2-hydroxy-5-(4-nitroazo)benzylidene)amino]ethoxy]-26,28-dihydroxy-calix[4]-arene (4), 5,11,17,23-tetra-tert-butyl-25,27-bis[2-[(2-hydroxy-5-(2-nitroazo)benzylidene) amino]ethoxy]-26,28-dihydroxycalix[4]arene (5), 5,11,17,23-tetra-tert-butyl-25,27-bis[2-[(2-hydroxy-5-(4-chloroazo)benzylidene)amino]ethoxy]-26,28-dihydroxycalix[4]arene (6), have been synthesized as an selective chromoionophore for Na+. The complexation behavior of ligands 4-6 with alkali metal ions Na+, K+, Rb+and Cs+ has been evaluated by using UV-Vis spectrometry in CH3CN-H2O (99:1/V:V) solution at 25°C. The UV-Vis spectra show that the complexation of 4-6 with Na+exhibits obvious bathochromic shifts (λmax 379→480 nm) and there is a unique color change in the solution from yellow to red upon complexation. The binding constants for Na+ are higher than that of other alkali metal ions, giving the highest cation selectivity up to 7 for Na+/K+. The binding ability and photophysical behavior of alkali cations by calix[4]arene derivatives 4-6 are discussed from the point of view of substituted effects at the lower rim of parent calix[4]arene and size-fit concept between host calix[4]arenes and guest cations. 相似文献
14.
15.
在不需外加还原剂的条件下一步原位合成了磺化硫杂杯[4]芳烃修饰的纳米金,并将其作为比色探针对金属离子进行检测。研究表明,磺化硫杂杯[4]芳烃修饰的纳米金能够选择性的识别CrP3+P,其检测限可达到1μM。 相似文献
16.
17.
Joanna Kulesza Marcin GuzinskiVeronique Hubscher-Bruder Francoise Arnaud-NeuMaria Bocheńska 《Polyhedron》2011,30(1):98-105
The synthesis, characterisation and X-ray crystal structures of p-tert-butyl-calix[4]arene-thioamide L and its complex with lead L-Pb2+ is reported. The cation-binding properties in solution have been assessed by liquid-liquid extraction of the metal picrates from water into dichloromethane and by stability constants determination in acetonitrile using UV-absorption spectrophotometry or potentiometry. The compound was used as active material in Pb-ion-selective membrane electrodes. The characteristics of these electrodes as well as the selectivity coefficients for Pb2+ cation versus many metal ions tested were obtained. Complex formation constants within the electrode membranes were determined using the sandwich membrane method and were compared to those obtained in acetonitrile. The lead concentration in the scrap-lead was determined with the use of electrodes incorporating the ligand studied. 相似文献
18.
A new tetranaphthyl-calix[4]arene (C4N4) was synthesized by a fourfold Sonogashira cross-coupling reaction, and exhibited high affinity and selectivity for p-nitrophenol (3c) by fluorescence spectroscopy. The NMR, AFM, IR, MALDI-TOF mass spectroscopy, and computational calculations revealed the formation of a host–guest complex driven by π–π stacking interactions. 相似文献
19.
Jinyu Shen H. Fred Koch D. Max Roundhill 《Journal of inclusion phenomena and macrocyclic chemistry》2000,38(1-4):57-67
Calix[4]arenes with both ligating and methoxy poly(ethylene glycol) groups appended have been synthesized using several approaches, involving the formation of sulfonyl ester groups on the wide rim, Schiff base derivatives on the narrow rim, and thioether groups on both the wide and narrow rims. These new derivatives have been characterized by a combination of infrared and 1H NMR spectroscopy. Compounds 10 and 11 are insoluble in both water and aqueous poly(ethylene glycol), but the other new compounds are soluble. 相似文献
20.
Chemoselective intramolecular ring closure on the phenolic OH groups of p-tert-butylthiacalix[4]arene-1,3-bis(N-ω-hydroxyalkylamides) attained under Mitsunobu conditions affords inherently chiral macrocycles capped by carboxamide bridges. Oxazoline or oxazine cyclization products derived from self-condensation of the hydroxyalkylamide moieties were not isolated. In one case the detection of enantiomers was achieved by chiral HPLC. 相似文献