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1.
通过对杯[4]芳烃以及杯[6]芳烃上缘进行烯丙基化和硅氢加成2步衍生化反应得到硅氢化杯[4]芳烃以及硅氢化杯[6]芳烃,再将这2种硅氢化杯芳烃衍生物分别接枝到超细SiO2上。在不同的pH值条件下,就2种杯芳烃接枝超细SiO2衍生物对水合Cu2+及Ag+的萃取性能进行了研究。结果表明,与对叔丁基杯芳烃相比较,杯芳烃接枝超细SiO2衍生物对Cu2+和Ag+的萃取率都有所提高,其中杯[4]芳烃接枝超细SiO2对Ag+的最高萃取率达到98.78%,杯[6]芳烃接枝超细SiO2对Cu2+的最高萃取率达到67.74%。  相似文献   

2.
A polymeric compound containing more than one calixarene molecule was synthesized by reacting the oligomer ( 2 ) with 25,26,27-tribenzoyloxy-28-hydroxy calix[4]arene. After basic hydrolysis of 3a , the polymeric calixarene ( 3b ) was utilized for selective extraction of some metal cations from aqueous phase to organic phase. It was found that the compound ( 3b ) was selective toward Fe3+ from an aqueous solution containing Cu2+, Ni2+, Co2+ and Fe3+ cations. The mechanism of the extraction process was discussed. © 1994 John Wiley & Sons, Inc.  相似文献   

3.
Abstract

Two new calixarene derivatives: 5,11,17,23-tetra-t-butyl-25,26,27,28-tetrakis-(piperidinocarbo-nylmethyoxy)calix[4]arene (L4) and 5,11,17,23,29,35,41,47-octa-t-butyl-49,50,51,52,53,54,55, 56-octa-(piperidinocarbonylmethoxy)calix[8]arene (L8), which show good binding abilities to metal ions, were synthesized by the reaction of the corresponding calixarene derivatives with piperidine. The ligand L4 is capable of separating a tight ion-pair formed by Pb2+ and the picrate anion in THF. The interactions of the new ligands (Ln n = 4, 8) with Na+, Pb2+ and Cd2+, in the presence or absence of picrate, were investigated by 1H NMR and electrospray mass spectrometry. It is found that L4 reacts with these metal ions to form a unique complex which can be described as [Mm+L4]m+ while L8 forms a variety of complexes depending on whether there are picrate anions in solution. [Mm+L8]m+ is formed in the absence of the picrate, and two complexes, [PbL8]·CH3CN·H2O and [PbNaL8]3+, are formed in the presence of the picrate. The higher conformational flexibility and larger macro-ring size of L8 account for the fact that it forms a variety of complexes as compared with L4.  相似文献   

4.
Five new polymeric compounds containing more than one calix[4]arene have been synthesized by reacting an oligomer with 5,11,17,23-tetrakis[(diethylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (L1), 25,27-dimethyl-26,28-dihydroxy-p-tert-butylcalix[4]arene diketone (L2), and p-nitrocalix[4]arene (L3), and chloromethylated polystyrene with 25,27-dimethyl-26,28-dihydroxy-p-tert-butylcalix[4]arene diketone (L4) and p-nitrocalix[4]arene (L5). These compounds were studied by the selective extraction of Fe3+ cation from the aqueous phase into the organic phase and was carried out by using compounds L1L5. It was observed that the polymer support attached to the lower rim of p-nitrocalix[4]arene was the most efficient carrier of Fe3+ in the extraction process.  相似文献   

5.
A series of new calix[4]arene(amido)mono-crown compounds have been synthesized through aminolysis of calix[4]arene esters and intramolecular cyclization of the intermediates. The title compounds were converted into their nitro and azo substituted derivatives to provide novel photoresponsive molecular receptors for transition metal ions. Single crystal X-ray analysis of calix[4]arene(ethyleneamido)mono-crown (2a) revealed that the compound is present in a cone conformation with an amido loop that caps the lower rim of calix[4]arene cavity to result in stacking along axis a and axis c to provide supramolecular aggregates in the solid state. Evaluation of synthesized macrocycles in the solution phase for recognition of transition metal cations (Cr3+, Fe2+, Co2+, Ni2+, Cu2+, Ag+, Cd2+, Pb2+, Hg+, Hg2+, Pd2+, and Pt2+) by UV-visible spectroscopy revealed that p-tert-butyl-calix[4]arene mono-(amidocrown) 1c selectively shows a blue shift at 38 nm on interaction with Hg+ ions.  相似文献   

6.
The development of sensors for the detection of transition metal ions has attracted a special attention because of the toxic impact of these elements on our environment. Due to their sensitivity, reliable, inexpensive and easy use for on site analysis, optical chemical sensors (optodes) have received an increasing attention for a rapid determination of toxic species in water. A new chromogenic calix[4]arene has been investigated on the basis of the high recognition properties of calixarenes associated to the optical response provided by their functionalization with a phenyl azo group. Thin tetrakis-(phenylazo) calix[4]arene amide derivative layers deposited on a glass suprasil substrate have been characterized by contact angle measurements showing a good surface coverage whereas a uniform morphology of the calixarene membrane in acetonitrile solvent was observed by scanning electron microscopy (SEM). The ability of the tetrakis-(phenylazo) calix[4]arene amide derivative thin film to complex Hg2+, Ni2+ and Eu3+ ions have been demonstrated by the modification of the calixarenes main absorption band at 343?nm and appearance of a new absorption band at 500?nm upon addition of Eu3+. The different sensors could be regenerated with hydrochloric acid. The dynamic concentration range, ion selectivity, response time, repeatability and reproducibility are discussed. These results are suitable to the development of optodes for the detection of metal pollutants.  相似文献   

7.
The structures and stability of outer-sphere associates of sulfonate derivatives of thiacalix[4]arene and calix[4]resorcinarene with coordinatively saturated cobalt(iii) bis- and tris-chelates ([Co(L-His)2]+, [Co(en)2ox]+, [Co(en)3]3+, and [Co(dipy)3]3+) were compared based on the data from UV, CD, 1D 1H NMR, and 2D (2D NOESY) 1H NMR spectroscopy and conductometry. Outer-sphere association is accompanied by partial penetration of the chelate rings of the complexes into the hydrophobic cavity of calixarene, which induces changes in the spectroscopic and spectropolarimetric properties of the cobalt(iii) complexes.  相似文献   

8.
The binuclear Co(II) complexes of calix[4]arene substituted 2-vanillin (R1) and 2-hydroxy naphthaldimine (R2), Schiff bases (Co2L1 and Co2L2) have been synthesized, characterized and employed as models to mimic monooxygenase in the catalytical oxidation of olefins. The kinetic mathematical model (oxygen rebound mechanism) for olefin cleavage catalyzed by the complexes has been proposed. The results show that, compared to the calix[4]arene-free analogous, the mono and multinuclear complexes of calix[4]arene Schiff bases as catalyst exhibit high activity in the olefin catalytic oxidation.  相似文献   

9.
Several new nitrogen-containingcalixarene derivatives have been synthesized andtheir ion-binding properties investigated byUV spectroscopy and solventextraction. These derivatives include5,11,17,23-tetra-t-butyl-25,26,27,28-tetrakis(piperidinocarbonylmethoxy)calix[4]arene (5),5,11,17,23,29,35,41,47-octa-t-butyl-49,50,51,52,53,54,55,56-octa(piperidinocarbonylmethoxy)calix[8]arene (6) and5,11,17,23,29,35,41,47-octa-t-butyl-49,50,51,52,53,54,55,56-octa(N,N-diethyl-car-bamoyl-methoxy)calix[8]arene(7). The UV spectra of and 7revealed they had an ability to transform tight lead picrate ionpairs into separated ones by complexationwith Pb2+ in tetrahydrofuran.Both derivatives give 1 : 1 complexes with Pb2+. Extraction studies showed that these derivativescould efficiently extract Pb2+ (as picrate salts) from the aqueous phase into chloroform. Theextractability of these derivatives were also compared with that ofthe oxygen-containing ester derivative calix[8]arene 2 and the other two nitrogen-containingcompounds 8 and 9.  相似文献   

10.
A novel calix[4]arene derivative with two ferrocenyl Schiff-base groups at the upper rim 3 has been synthesized from 5,17-diformyl-25,27-dipropoxy-26,28-dihydroxy calix[4]arene and 4-ferrocenylaniline via condensation reaction. Reduction of 3 with sodium borohydride led to calix[4]arene derivative 4 with two amino ferrocenyl groups at the upper rim. The ferrocenyl Schiff-base calix[4]arene and its corresponding reduced amine have been purified and characterized by elemental analysis,1H NMR, FTIR, Mass and UV-vis spectral data. Electrochemical properties of compounds 3 and 4 have been investigated. Cyclic voltammograms of 3 and 4 show reversible redox couples of ferrocene/ferrocinium at E1/2=0.401 V and 0.346 V, respectively. Electrochemical studies show these redox active compounds electrochemically recognize trivalent lanthanides La3+ and Ce3+ and divalent Pb2+ and Cu2+cations. With ferrocenyl Schiff-base calix[4]arene 3 an anodic shift as large as 130 mV is observed on addition of one equivalent of Ce3+ ion. Also extraction properties of compound 4 towards some metal cations have been described. It has been observed that compound 4 has a good selectivity for metal cations Fe3+, Cu2+, Pb2+ and Cd2+ against Ni2+ and Co2+.  相似文献   

11.
The inclusion of small neutral organic guests (C6H14, CH2Cl2, CH3OH) by calix[4]arene receptors was found by 1H NMR spectroscopy and microanalysis. The studied calix[4]arenes can form stable intramolecular complexes with solvent molecules which keep the stoichiometric composition without changing under conditions of the sublimation experiment. The saturated vapour pressures of calix[4]arenes and complexes of calix[4]arenes with solvent molecules were determinated for the first time by the Knudsen’s effusion method in the wide temperature range. The changing of standard thermodynamic parameters of complexation by transfer process from condensed state to vapour phase was estimated. It was shown that the large flexibility of the calixarene ligand structure corresponds to a strongly negative entropic contribution as well as negative enthalpy term to the Gibbs energy of formation of host–guest complexes in the gas phase.  相似文献   

12.
Two novel calix[4]arene receptors containing ferrocene units in cone (L1) and 1,3-alternate (L2) conformations have been synthesized from 25,27-dihydroxy-26,28-bis[(3-aminopropyl)oxy]calix[4]arene 4 or 25,26,27,28-tetra[(3-aminopropyl)oxy]calix[4]arene 6 and ferrocenecarboxaldehyde via condensation, respectively. Their structures have been characterized by 1H, 13C, APT, COSY NMR, FTIR, HSMR, and UV–vis spectral data. The electrochemical behavior of L1 and L2 has been investigated in the presence of F?, Cl?, Br?, H2PO4?, CH3COO? anions. Electrochemical studies show that these receptors electrochemically recognize CH3COO?, H2PO4?, and Cl?, anions. Using an UV–vis study, the selectivity to these anions in DMSO solution was confirmed.  相似文献   

13.
Anthracene anchored 1,3-di-derivatives of lower rim p-tert-butyl-calix[4]arene were synthesized and characterized. These derivatives were subjected to the binding studies with the divalent metal ions, viz., Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+ and Zn2+ using fluorescence and absorption spectra. The imine moiety that is in conjugation with the anthryl unit is responsible for quenching the fluorescence in the absence of metal ion, however, in the presence of Fe2+ and Cu2+, the spectra showed very high enhancement in fluorescence intensity indicating that the lone pair present on the imine-N is involved in the metal ion binding and as a result the photo-induced electron transfer is prevented. Based on the photo-physical studies, it has been found that the anthracene derivative that is coupled with the calix[4]arene unit through an imine bond acts as a chemosensor for Fe2+ and Cu2+. The fluorescence studies are further augmented by the absorption spectra.  相似文献   

14.
The influence of metal cations (Li+, Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, Ag+, Cd2+, Co2+, Fe2+, Hg2+, Mn2+, Pb2+, Zn2+ and Fe3+) on the spectroscopic properties of two dansyl (1-dimethylaminonaphthalene-5-sulfonyl) groups linked to the lower rims of a series of three, structurally related, di-ionized calix[4]arenes was investigated by means of absorption and emission spectrophotometry. Di(tetramethylammonium) salts of the di-ionized ligands, (TMA)2L1, (TMA)2L2 and (TMA)2L3, which differ in having zero, two and four tert-butyl groups, respectively, on the upper rim of the calix[4]arene scaffold were utilized for the spectrofluorimetric titration experiments in acetonitrile. On complexation by alkaline earth metal cations, both the absorption and emission spectra undergo marked red shifts and quenching of the dansyl fluorescence. These effects are weaker with alkali metal cations. Transition metal cations interact strongly with the ligands. In particular, Fe3+, Hg2+ and Pb2+ cause greater than 97% quenching of the dansyl fluorescence in the di-ionized ligands.  相似文献   

15.
The novel chiral polymeric compounds containing more than one calix[4]arene have been synthesized by reacting a new calix[4]arene diamine derivative with two chiral monomers. These newly prepared compounds were studied by extraction of toxic heavy metal (Cu2+, Co2+, Cd2+, Hg2+), silver and alkali metal (Na+, K+) cations from aqueous phase. It was observed that the resulting calixarene-based polymers have a good complexing ability towards silver, alkali metal and toxic heavy metal cations.  相似文献   

16.
In this study, seven new compounds p-(4-butyl-phenylazo)calix[6]arene(1), p-(4-(phenylazo)phenylazo)calix[6]arene (2),p-(4-hydroxyphenylazo)calix[6]arene (3),p-{4-[N-(thiazol-2-yl)sulfamoyl]phenylazo\}calix[6]arene(4), p-(4-acetamidophenylazo)calix[6]arene (5),p-(thiazol-2-ylazo)calix[6]arene (6) andp-(2-sulfanylphenylazo)calix[6]arene (7) have been synthesizedfrom calix[6]arene by diazo coupling with the corresponding aromaticamines. UV-Vis, IR, 1H and 13C NMR spectral data have been used to elucidate the structures of the compounds elemental analyses  相似文献   

17.
李广科a  b  刘敏a  b  杨国强a  陈传峰  a  黄志镗  a 《中国化学》2008,26(8):1440-1446
我们方便地合成了上沿修饰四丹磺酰胺基团的杯[4]芳烃衍生物1,发现该化合物在含50%水的乙腈中显示出对汞离子高选择性和灵敏性的识别作用,竞争实验表明多数金属离子对其检测干扰较小。机理研究结果表明荧光萃灭源于由丹磺酰胺基团到汞离子的光致电子转移过程。另外,通过研究1和1-Hg2+的荧光衰减实验,以及对比双丹磺酰胺杯[4]芳烃2和单丹磺酰胺杯[4]芳烃3对汞离子的识别作用,发现化合物1的四丹磺酰胺基团具有很好的预组织和协同作用。化合物1对汞离子的检测限为3.41×10-6 mol·L-1,这可以使1成为一个潜在的汞离子荧光化学传感器。  相似文献   

18.
The cone-shaped calixarene N-chalconeamides were synthesized by the reaction of calix[4]arene carboxylic acids or acid chlorides with aminochalcones. It was found, that calixarene chalconeamides influence the Mg2+, ATP-dependent Ca2+ accumulation in mitochondria and sarcoplasmatic reticulum of the smooth muscle cells.  相似文献   

19.
The synthesis and calcium-selective chromogenic ion binding properties of benzothiazolium derivative of calix[4]arene are described. The merocyanine-type ionophore derived from calix[4]arene-diamide showed selective chromogenic properties toward Ca2+ ions in aqueous methanol. The compound showed significant Ca2+ ion dependent changes in UV-vis spectral properties in the presence of other physiologically important metal ions (Na+, K+, and Mg2+). The pH sensitive chromogenic behavior also suggests that the compound can be used as a sensitive pH indicator around pH 6.5.  相似文献   

20.
The influence of Li+, Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, Ag+, Cd2+, Co2+, Fe2+, Hg2+, Mn2+, Pb2+, Zn2+ and Fe3+ on the spectroscopic properties of two dansyl (1-dimethylaminonaphthalene-5-sulfonyl) groups linked to the lower rims of a series of three, structurally related, di-ionized calix[4]arenes is investigated by means of absorption and emission spectrophotometry. Di(tetramethylammonium) salts of the di-ionized ligands, L, L1, and L2, which differ in having no, two and four allyl groups, respectively, on the upper rim of the calix[4]arene scaffold, are utilized for the spectrofluorimetric titration experiments in MeCN. On complexation by alkaline earth metal cations, the emission spectra undergo marked red shifts and quenching of the dansyl fluorescence. These effects are weaker with alkali metal cations. Transition metal cations and Pb2+ interact strongly with the ligands. In particular, Fe3+, Hg2+ and Pb2+ cause greater than 99% quenching of the dansyl fluorescence.  相似文献   

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