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1.
Fullerenehasgeneratedarapidlygrowingandactiveresearchareal.InclusioncomplexesoffullerenehavebeenpreparedforCoowithavarietyofhostsystemsincludingcalixarenes,cyclotriveratrylene,andy-cyclodextrin.TheselectiveformationofaclathratefromCooandcall-c[8]areneswasexcellentlyutilizedfortheseparationofCooandC,,'.HereinwereportthatCoocanbeincludedinthecavityofanewkindoffunctionnedcalixlslarene,p-tert-butylcall-c[8]arenetetraphenylether(1).ThefixtureofCooand1(lfZmolarratio)wasrefluxedintoluenefor2--3h,d…  相似文献   

2.
Depending on the initial concentrations of fullerene (C60) and p-tert-butyl calix[8]arene (C[8]A) in toluene, two regimes of their interaction were distinguished. The changes in optical absorption of C60:C[8]A mixed solutions observed over a period of time suggest that the following consecutive processes take place upon interaction between C60 and C[8]A in toluene: (1) molecular inclusion, and (2) growth and sedimentation of the insoluble C60/C[8]A clusters. At increased concentrations of the components, process (2) is suppressed and stable C60/C[8]A colloids can be formed. Spectral features of these colloids in different solvents clearly indicate the difference between self-aggregated C60 and small clusters of the complex. A specific influence of the C[8]A cage on the entrapped C60 molecules is also confirmed by IR spectroscopy of the complex in the solid state.  相似文献   

3.
 激光抽运和自旋交换的超极化 129Xe 核磁共振是近几年发展起来的一种新方法,它比普通 129Xe 核磁共振的检测灵敏度提高约104 ~105倍,是研究材料孔结构和孔内粒子分布的强有力工具. 本文介绍了超极化 129Xe 核磁共振技术并综述了其在多孔催化材料研究中的应用,特别是对催化反应中广泛使用的无机微孔和介孔材料中的应用进行了详细的讨论. 最后展望了此技术的应用前景.  相似文献   

4.
This article reports the synthesis and the properties of 5,11,17,23-tetra(t-butyl)-25,27-bis-(ethoxy-1,8-naphthalimide)-26,28-hidroxy-calix[4]arene and the formation of an inclusion compound in organic medium. This functionalized calix[4]arene was conceived as the association of a potential host species with a good fluorophore for optical sensoring purposes. Calix[4]-NI as we will call it, maintains its ‘cone-pinched’ configuration and exhibits typical naphthalimide fluorescence bands in non-polar solvents. Its ability to interact with guest species via hydrogen bonding in its endo-hydrophilic cavity to form inclusion compounds was verified with absorption and fluorescence measurements using N-ethanol-1,8-naphthalimide as guest species, which was projected to fit exactly the host cavity and to interact with its naphthalimide π electrons. For this reason, it was possible to follow the formation of the inclusion compound with electronic spectroscopy.in final form: 17 November 2004.This revised version was published online in July 2005 with a corrected issue number.  相似文献   

5.
CrystalStructureofCalix[4](dioxo)crown-6Acetonitrile(1:3)InclusionComplexZHONGZhen-Lin;CHENYuan-Yin;LUXue-Ran(DepartmentofChe...  相似文献   

6.
Chromium(VI) is one of the major toxic elements present in environmental samples. The polymer inclusion membrane (PIM), has been developed to provide metal ion transport with high selectivity. This study was conducted to discover efficient methods for removing Cr(VI) from wastewater. A functionalized calix[4]arene carrier 1 in a PIM system was used to transport Cr(VI) from an acidic aqueous donor phase solution to an acceptor phase that contained an acetic acid/ammonium acetate solution at pH 6. The prepared PIM was characterized with Fourier Transform Infrared (FT-IR) spectroscopy and the Atomic Force Microscopy (AFM) techniques as well as with contact angle measurements. The efficiency of Cr(VI) transport through the PIM was investigated by studying the effects of carrier concentration on the membrane phase as well as by measuring the amount of plasticizer in the membrane, the pH in the acceptor phase and the membrane's stability and thickness. The kinetic parameters were calculated as rate constant (k), permeability coefficient (P), flux (J) and diffusion coefficient (Do). The transport efficiency of Cr(VI) was observed to be 98.61% after 10 h under optimized conditions. The experimental results show that Cr(VI) can transport from the donor phase to the acceptor phase with high efficiency through the PIM. The results also suggest that the transport efficiency of the PIM was reproducible and that a PIM is effective for long-term separation processes.  相似文献   

7.
近年来 ,杯芳烃衍生物与稀土离子配合物的发光因在荧光免疫分析和发光材料的开发上具有潜在的应用价值而引起了人们极大的兴趣 [1~ 3] .人们已经合成了一系列带有羧基、吡啶和羰基等官能团的杯 [4]芳烃衍生物 ,并在非水溶剂中能敏化稀土离子发光 ,但在水溶液中效果并不理想 [4~ 7] .本文报道Scheme1  The structure of calix[4]arenesulfonate水溶性杯 [4]芳烃衍生物与稀土铽 [ ]离子形成配合物的荧光行为 .结果表明 ,乙酸修饰的磺化杯 [4]芳烃 L2 在水溶液中不仅能对 Tb3+进行有效的能量传递 ,形成高效的能量传递发光体系 ,而且也能与…  相似文献   

8.
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   

9.
Abstract

Recognition ability of both cationic pillar[5]arene and calix[4]arene has been studied in aqueous media. Anion complexation can be evaluated from their ability to complex their counterions as well as an added external organic anion. DOSY NMR experiments and fluorescence quenching show that pillararenes have a larger ability for including their own counterions than calixarenes irrespective of the anion (tetrafluoroborate or chloride or bromide) and the structure of the cationic moiety (trimethylammonium or methylimidazolium). Counterion complexation shows a picture where four to five positive charges of the pillar[5]arene are neutralised, meanwhile only one positive charge of the calixarene is neutralised for a 1 mM solution of the macrocycle. Irrespective of the smaller net positive charge in the pillar[5]arene, its binding ability for organic anions (toluenesulfonate or hydroxybenzoate) is larger than for calix[4]arene allowing a better accommodation of the guest in its cavity. The larger separation between the cationic groups of the receptor and its electron-rich aromatic region improves the anion recognition ability for pillar[5]arene.  相似文献   

10.
X-ray crystal structures of the inclusion complexes of calix[4]arene monomethoxycarboxylic acid 1 (C30H2606) with acetontrile and acetone are reported. The crystal of C30H26O6·CH3CN is of monoclinic, space group P2 1/c with a = 11.691(5), b = 13.753(5), c = 17.072(7)A, β = 100.104(7)°, C32H29NO6, Mr = 523.56, V = 2702.4(18)A^3, Z = 4, De= 1.287 g/cm^3, μ(MoKα) = 0.089 mm^-1, T = 293(2) K, 5570 independent reflections with 3220 observed ones (1 〉 2σ(I)), R = 0.0521 and wR = 0.1132 with GOF = 1.042 (R = 0.1055 and wR = 0.1350 for all data). The data for C30H26O6·CH3COCH3: monoclinic, space group P2 1/c, α = 12.366(4), b = 12.119(4), c = 18.796(6) A, β = 90.871(6)°, C33H32O7, Mr = 540.59, V = 2816.6(16)A^3, Z = 4, Dc = 1.275 g/cm^3, μ(MoKα) = 0.089 mm^-1, T = 293(2) K, 5783 independent reflections including 2580 observed ones (I 〉 2σ(I)), R = 0.0555 and wR = 0.1424 with GOF= 0.975 (R = 0.1601 and wR = 0.1884 for all data). Their architectures exhibit one-dimensional inclusion polymers which are mediated head-to-tail by the guests.  相似文献   

11.
The interaction of 1,3-alternate tetrapropoxycalix[4]arene (1) with n-butylammonium ion (2) in CD(2)Cl(2) was examined using (1)H, (13)C and (14)N NMR spectroscopy and DFT (density functional theory) calculations. NMR shows that 1 forms with 2 an equimolecular hydrogen-bonded complex with the equilibrium constant 5.91 x 10(3) l/mol at 296 K. The structure of the complex can be shown to be asymmetric at 203 K, with 2 interacting by hydrogen bonds with the two ethereal oxygen atoms of one half of 1 and with the pi system of the other half, but is rapidly averaged to an apparent C(4h) symmetry by chemical exchange at higher temperatures. Using two related but independent techniques based on transverse and rotating-frame proton relaxation, it is shown that only an intermolecular exchange of 2 between the bound and free states takes place, in contrast to previously studied interaction of 1 with H(3)O(+). Its correlation time is 0.169 ms. It is shown by DFT calculations that such swift exchange is not possible without a cooperative interaction of both 2 and 1 with several molecules of water present. Similarities and contrasts between the exchange processes of 2 and H(3)O(+) bound to 1 are discussed, in particular with respect to the apparent quantum tunneling of the latter inside the molecule of the complex.  相似文献   

12.
LI  Liang  GU  Weiwei  YAN  Chaoguo 《中国化学》2009,27(10):1975-1980
Four p‐tert‐butylcalix[4]arene derivatives with different Schiff base groups at the lower rim were efficiently prepared in three steps. p‐tert‐Butylcalix[4]arene was firstly O‐peralkylated with ω‐haloalkylphthalimide in the system of NaH/DMF to give calixarene tetraalkylphthalimides, which were in turn hydrazinolyzed to give tetraaminoalkylcalixarenes. Then by condensation of the latter with salicylaldehyde and 2‐hydroxy‐1‐naphthaldehyde, a series of calixarene Schiff bases were obtained in satisfying yields. The complexing properties of these Schiff bases for transition metal ions were investigated with UV spectroscopy.  相似文献   

13.
The stability constants (log K), the reaction enthalpy( H) and entropy ( S) of the complexesformed between some amino acids (glycine, L-alanine,L-valine, L-leucine, L-phenylalanine, L-tryptophan,L-threonine, and L-lysine) and peptides (glycyl-glycine,glycyl-L-alanine, glycyl-L-leucine, glycyl-L-phenylalanine,L-leucyl-glycine, L-leucyl-L-alanine, glycyl-L-valine,L-leucyl-glycyl-glycine, and glycyl-glycyl-glycine) withp-sulfonatocalix[4]arene and hexasodiump-sulfonatocalix[6]arene in aqueous solutions by meansof calorimetric titration have been investigated. The reportedresults demonstrate that the amino acids and peptides under studyform complexes with both p-sulfonatocalix[4]areneand hexasodium p-sulfonatocalix[6]arene. In the case of theamino acids and peptides the complexation with water-solublecalixarenes in aqueous solution is favored by enthalpiccontributions and disfavored by entropic contributions. However,no influence of the ring size of the calixarenes upon thecomplexation is observed. By comparison with the reaction ofthe sodium salt of phenol-4-sulfonic acid with amino acids amacrocyclic effect in case of the calixarenes is possible.  相似文献   

14.
As a new member of the water‐soluble calixarene family, p‐sulfonatothiacalix[4]arene possesses unique properties resulting from its inherent structural characteristics. In our recent research, we have investigated the self‐assembly of bowl‐like p‐sulfonatothiacalix[4]arenes with or without transition‐metal ions in the presence of suitable guests. We have obtained a series of compounds with different structural motifs, such as capsules, tetranuclear clusters, and molecular clefts. In addition, p‐sulfonatothiacalix[4]arenes show good inclusion abilities and can capture different guests by utilizing their hydrophobic cavities through supramolecular interactions. Even when a cone‐like conformation is fixed, the p‐sulfonatothiacalix[4]arene can also splay its opposite aromatic rings apart to adjust its cone‐like conformations from C4v to C2v and even lower symmetries. All of these show that it is a good candidate for the research of inclusion phenomena. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 155–168; 2009: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.200800033  相似文献   

15.
Biscalixarenes, as examples of higher order molecular architectures than normal calixarene derivatives, were studied extensively in the recent years due to they possess two calixarene cavities which have the potential for complexing with two guests in two…  相似文献   

16.
卢奎  苑乃香  周稚仙  吴养洁 《应用化学》2002,19(10):958-962
配位作用;液膜传递;四乙氧羰基甲氧基杯[4]芳烃的合成与性质  相似文献   

17.
In this paper we report evidence for an inclusion complex between carbon dioxide and p-t-butylcalix[4]arene. The complex was studied with infrared spectroscopy,single-crystal X-ray diffraction, solid-state NMR, and thermogravimetric analysis.Results indicate that 70% of the p-t-butylcalix[4]arene cavities could be occupiedby a CO2 molecule following exposure at 30 MPa and 40 °C.  相似文献   

18.
The Sc(OTf)3-catalyzed mixed cyclocondensation of bis-1,2-(2,6-dihydroxyphenyl)ethane and 2-hexylresorcinol gave a singly bridged double-resorcinarene bearing sixteen hydroxyl groups at the peripheral positions. In methanol, the double-resorcinarene binds quaternary ammonium ions to form capsular-type 1:1 complexes.  相似文献   

19.
The stability constants, enthalpy ΔH 0, entropy ΔS 0, and Gibbs energy ΔG 0 were determined for the host–guest complexes (1:1) of calix[4]arene bis-hydroxymethylphosphous acid with glycine, l-alanine, l-valine, l-leucine, l-isoleucine residues in methanol solution with the aid of the titration experiments followed by calorimetric and spectroscopic (1H NMR, UV) methods. The experimental data indicated that the host–guest complexation was under control of the direct electrostatic interaction between negatively charged calixarene phosphoryl group and amino acid residue NH 3 + group, modulated by the hydrophobic interaction, which drive the inclusion of the residue alkyl side-chain into the calixarene cavity. The stability of the inclusion complexes was found correlated with the size of the aliphatic amino acid’s side-chain. The experimental data were additionally analyzed in the terms of the three state model corresponding to coexistence of 2:1 and 1:1 complexation equilibria.  相似文献   

20.
IthasbeenshownthatcalixarenescanperformselectiveiontranspoFtandformneutralcomplexeswithcanonsthroughprotonlossl.Olmsteadreported'thesynthesisandXraycrystalstructuresofTitanium(IV),Iron(ill)andCobalt(II)complexesofp-tertbutylcalix[4]areneandfoundthatacompleteexchangeofallfourOHgroupsinp-lertbutylcalix[4]arenetookplacewhentreatedwithTi(NMe=).togivethearyloxocomplex[{Ti(p-lerl-butylcalix[4]arene)},]'6whichmaybeformallydescribedasacentrosymmetrictitaniumaryloxidedimerconsistingoftwoTi(P-lerl…  相似文献   

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