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21.
Teresa Borowiak Maciej Kubicki Grzegorz Dutkiewicz Marek Pietraszkiewicz Oksana Pietraszkiewicz 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(3-4):181-189
Two newly identified supramolecular structures arise from self-assembly of the macrocyclic 1,5,9,18,22,26- hexaaza[11.11]-p-cyclophane salts with o-nitrophenol (C28H50N6)4+·4(C6H4NO2O)− (1) and with HCl (C28H52N6)6+·6Cl-·4H2O (2). In both cases two-dimensional supramolecular sheets are formed. 相似文献
22.
Lampeka Ya. D. Manorik P. A. Pogorelaya L. M. Prikhod'ko A. I. 《Theoretical and Experimental Chemistry》2002,38(5):342-346
The interaction of mono- and oligomacromolecular complexes of copper(II) and nickel(II) with water vapor has been studied on a piezoquartz microbalance. It has been established that the effectiveness of adsorption is determined by the nature of the metal ion to a larger extent than the quantity of macrocyclic ligand in the receptor molecule. Oligomacrocyclic complexes of copper(II) are shown to have prospects for use as active coverings of moisture meters working over a wide range of relative humidity. 相似文献
23.
Baxter PN 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(11):2531-2541
The new twistophane 4 has been synthesised, which comprises a conjugated dehydropyridoannulene-type macrocyclic scaffold with outwardly projecting nitrogen-donor sites for the purpose of metal ion coordination. The macrocyclíc structure of 4 was assigned by using spectroscopic methods, and shown to exist in a twisted and chiral ground state conformation by semi-empirical theoretical calculations. A detailed spectroscopic investigation into the metal ion binding properties of 4 and precursor 11 revealed that they functioned as selective complexants, affording a fluorescence quenching output response characteristic of Pd(II) and Hg(II) ions. Furthermore, 4 also signalled the presence of Fe(II), Co(II), Ni(II) and Ag(I) ions by the precipitation of coordination polymers, and exhibited reversible proton-triggered fluorescence quenching behaviour. Macrocycle 4 thus represents a unique type of molecular sensory platform, which may find a wealth of potential applications such as the detection of heavy-metal pollutants, as well as for the fabrication of proton-switchable materials and coordination polymers with novel electronic and magnetic properties. 相似文献
24.
The mononuclear macrocyclic polyamine metal complexes 5a-5e have been shown to form stable 1 : 1 complexes with bases and nucleosides. Their binding constants (K) were determined by UV-visible spectrometric titration. The results show that recognition ability of the complexes 5a--5e for uracil, U (Uridine), dT (Thymidine) is higher than that for the other bases or nucleosides (such as Cytidine, Guanosine, Adenosine). The metal ion also plays an important role for the recognition ability of complexes. 相似文献
25.
ZHANG Xingwen HU Lijiang HUANG Yudong SUN Dezhi & SUN Yi . Department of Applied Chemistry Harbin Institute of Technology HUANG Yudong Harbin China . Department of Environmental Engineering Harbin Institute of Technology Harbin China . Department of Experimental Mechanics Harbin Institute of Technology Harbin China 《中国科学B辑(英文版)》2004,47(5):388-395
Silsesquioxanes (SSO) or polyhedral oligomericsilsesquioxanes (POSS) are generally prepared frommolecular precursors using the hydrolytic condensa-tion of trialkoxysilane, RSi(OR')3. They are organic/inorganic hybrid nanostructural blocks with theircomplete general formula Tn(T = RSiO1.5, n = 1,2, …), and the incomplete generic formula is Tn-(OH)x(OR')y[x, y = 0, 1, 2, …, T= RSiO1.5 ?(x+y)/2n][1,2].Each VSSO, possessing a certain structural formulaand molecular weight, may h… 相似文献
26.
铜(II)-5-取代邻菲啰啉-二氧四胺大环三元体系的稳定性研究 总被引:1,自引:0,他引:1
The stability of copper (Ⅱ)-13-(2'-Hydroxy-3',5'-substituted benzyl)-1,4,8,11-tetraazacyclotetradecane-12, 14-dione(RTADO-14) binary complex compounds and of copper (Ⅱ)-5-substituted-1,10-phenanthrolines(R'TADO)-RTADO-14 ternary complex compounds was studied by means of pH titration method at 25.0±0.1 ℃ and I=0.1mol?dm-3KNO3. The formation constants of binary and ternary complexes were obtained. The structures of the binary and ternary complxes and the effects fo substituents on macrocyclic ligands and on R'Phen were also discussed. 相似文献
27.
Tezuka Y 《Chemical record (New York, N.Y.)》2005,5(1):17-26
A collection of recent developments in topological polymer chemistry is presented. First, topological isomerism occurring on randomly coiled, flexible polymer molecules having cyclic and linear structures is discussed. Second, an electrostatic self-assembly and covalent fixation strategy has been developed for the synthesis of polymeric topological isomers. These isomers have double cyclic, manacle-, and theta-shaped constructions, and are prepared by using either linear or star telechelic polymer precursors having moderately strained cyclic ammonium salt groups, which carry multifunctional carboxylate counteranions. A technique of reversed-phase chromatography (RPC) is demonstrated as an effective means to separate polymers with different topologies, especially polymeric topological isomers. A further extension of topological polymer chemistry has been observed by dynamic selection from electrostatic polymer self-assembly to enable the effective formation of tadpole-shaped, cyclic-linear hybrid topologies. 相似文献
28.
Tatsuya Oshima Masahiro Goto Shintaro Furusaki 《Journal of inclusion phenomena and macrocyclic chemistry》2002,43(1-2):77-86
A series of calixarene carboxylic acid derivatives were synthesized for the extraction of amino acids. A calix[6]arene carboxylic acid derivative showed the highest extractability to the target tryptophan ester. The main driving forcefor the complexation was the interaction between the ammonium cation of the aminoacid and the oxygen atoms of the host molecule. Stripping of amino acids was alsoaccomplished by contacting the organic solution with a fresh acidic solution. Basedon slope and Job method analyses, it was confirmed that the calix[6]arene formsa 1 : 1 complex with the amino acid ester. The structure of the complex between the calix[6]arene and the amino acid was investigated by 1H-NMR and CD spectra. The calix[6]arene includes a guest molecule in the cavity, and the inclusion induces the asymmetrization of the host molecule. This host compound functions as a novel recognition tool for amino acids. 相似文献
29.
30.
Griffiths PC Fallis IA Willock DJ Paul A Barrie CL Griffiths PM Williams GM King SM Heenan RK Görgl R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(8):2022-2028
The morphology of micelles formed by two novel metallosurfactants has been studied by small-angle neutron scattering (SANS) and small-angle-X-ray scattering (SAXS). The two surfactants both contain a dodecyl chain as the hydrophobic moiety, but differ in the structure of the head group. The surfactants are Cu(II) complexes of monopendant alcohol derivatives of a) the face-capping macrocycle 1,4,7-triazacyclanonane (tacn), and b) an analogue based upon the tetraazamacrocycle 1,4,7,10-tetraazacyclododecane. Here, neutron scattering has been used to study the overall size and shape of the surfactant micelles, in conjunction with X-ray scattering to locate the metal ions. For the 1,4,7,10-tetraazacyclododecane-based surfactant, oblate micelles are observed, which are smaller to the prolate micelles formed by the 1,4,7-triazacyclononane analogue. The X-ray scattering analysis shows that the metal ions are distributed throughout the polar head-group region, rather than at a well-defined radius; this is in good agreement with the SANS-derived dimensions of the micelle. Indeed, the same model for micelle morphology can be used to fit both the SANS and SAXS data. 相似文献