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1.
The binding properties of two phenylketones (2a and 3a) and two ethylesters (2b and {3b) derived from p-tert-butyldihomooxacalix[4]arene or from p-tert-butylcalix[4]arene, in the cone conformation, towards transition (Ag+, Ni2+, Cu2+, Co2+, Zn2+, Fe2+ and Mn2+) and heavy (Cd2+, Hg2+ and Pb2+) metal cations have been determined by extraction studies with metal picrates and liquid membrane transport experiments with the same salts. The affinity of these ligands for Ag+ has also been investigated by 1H NMR spectroscopy. Both ketones are better extractants than the esters, and show a strong preference for Ag+, while Cu2+ is the most extracted cation with the esters. 1H NMR titrations with AgSO3CF3 indicate 1 : 1 complexes for all ligands, those with ketones are more stable, on the NMR time scale, than those with esters. Both esters are good carriers for Ag+, and 2b exhibits the highest transport rate (4.7 mol h-1) found until now with dihomooxacalix[4]arene derivatives.  相似文献   

2.
A new series of crown compounds crownopaddlanes 3a-c bearing three cyclobutane rings were prepared by means of intramolecular [2+2] photocycloaddition of styrene derivatives. The yield of crownopaddlane 3b possessing five ethereal oxygen atoms was remarkably high 52% with the addition of sodium borofluoride in the photoreaction system. As this template effect suggests, 3b showed extraordinarily high Na+-selectivity with high efficiency on the liquid-liquid extraction of alkali metal picrates, though 3a having four ethereal oxygen atoms did not extracted any cations in this system. The high Na+-selectivity of 3b was further clarified by the equilibrium stability constants (log Ka) for Na+ (5.85) and K+ (2.91) in acetonitrile solution. The complexation of 3b to Na+ cation was also examined by X-ray crystallography. Crownopaddlane 3c bearing six ethereal oxygen atoms also efficiently and selectively extracted alkali metal cations, compared with conventional 18-crown-6 derivatives.  相似文献   

3.
合成了基于下缘含有酰肼基团的硫杂杯芳烃衍生物的银离子载体1,其核磁研究证实硫杂杯芳烃以1,3-交替构象存在,并且通过非竞争萃取实验和竞争萃取实验研究了它对碱金属和过渡金属离子(Li+, Na+, K+, Cs+, Co2+, Ni2+, Cu2+, Zn2+ and Ag+)的键合能力和选择性。实验结果表明:将酰肼基团引入1,3-交替构象的硫杂杯芳烃骨架的下缘可以提高其对Ag+的键合能力和选择性,同时,对Cu2+的萃取能力较弱,对碱金属离子和其它的重金属离子几乎没有萃取能力。进一步的核磁滴定和电喷雾质谱实验显示化合物1与银离子形成配合物的配合计量比为1:1,由此推断主要由“N-Ag+”配位键以及硫杂杯芳烃骨架的协同作用构成了化合物1与银离子的配合模式。  相似文献   

4.
Bis-crown ethers in which the benzo-15-crown-5 units were linked to 1,1′-positions of metallocene (M = Fe or Ru) with amide, ester, or ? C? C? bonds were synthesized. Complexing ability of the compounds with alkali, alkali earth, and transition metal cations were measured by the solvent extraction method. The results showed that these crown ethers had high affinity toward alkali metal cations (Li+, Na+, K+, and Rb+) and heavy-metal cations (Ag+ and Tl+). The difference of complexing ability for metal cations between ferrocene and ruthenocene derivatives could not be detected significantly. The extractability of metallocene-bis-crown ethers for metal cations was more larger than that of the corresponding mono-crown ethers, and irregular increments of extractability were explained by assuming the existence of a mixture of 1:1 and 2:1 complexes.  相似文献   

5.
Double-armed and tetra-armed cyclen-based cryptands (1a1d and 2) that bridge two aromatic rings by diethyleneoxy and triethyleneoxy units were prepared. The CSI-MS of 1:1 mixtures ([Ag+]/[ligand]) indicated that these new cryptands form 1:1 complexes with Ag+. The log K values for the interaction between Ag+ and 2 was greater than those of 1a1d, double-armed cyclens (3a3c and 4), and tetra-armed cyclen (5). The Ag+-ion-induced 1H NMR spectral changes suggest that the Ag+π interactions of the Ag+ complexes with the cryptands (1a1d and 2) are stronger than those in Ag+/double-armed and tetra-armed cyclens. To visualise the Ag+?π interactions, the isosurfaces of the LUMO and HOMOs of the Ag+ complexes were calculated at the B3LYP/3–21G(*) theoretical level. The LUMO of the Ag+ ion is distorted by interaction with the HOMOs of the aromatic side arms. The calculations reveal Ag+?π interactions between the Ag+ ion and the aromatic side arms, and these are shown graphically.  相似文献   

6.
Four imidazolyl acetamido p-tert-butylcalix[4]arenes 5–8 have been prepared by reacting the corresponding methyl esters derivatives 1–4 with histamine in 1:1 mixture of methanol:toluene. The yields ranged from 56 to 68%. 5–8 have been shown to be in cone conformation. The complexation behaviour of 5–8 towards monovalent metal picrates M+Pic with M+ = Li+, Na+, K+, Rb+ and Cs+ and divalent metal picrates M2+(Pic)2 with M2+ = Mg2+, Ca2+, Sr2+, Ba2+, Pb2+, Cd2+, Zn2+ and Co2+ are given. Tentative localisation of the metal cations in the receptors is given. The binding properties towards these cations have been determined along with stoichiometries of the complexes.  相似文献   

7.
New benzo-15-crown-5 derivatives containing nitro, amine and imine groups were prepared. Nitro compound (1) was prepared after the reaction?4′,5′-bis(bromethyl)benzo-15-crown-5 and o-nitrophenol in the presence of NaOH. After reduction process by using hydrazine hydrate and Pd/C amine compound (2) was formed. New crown ether imine compounds (35) were synthesized by the condensation of corresponding crown ether diamine (2) with salicylaldehyde derivatives. Sodium complexes of the crown compounds (1a5a) form crystalline 1:1 (Na+: ligand) complexes with sodium perchlorate. Nickel(II) complexes (3b5b) with 1:1 (Ni2+:ligand) stoichiometries were also been synthesized from the Schiff bases (35). The results indicated that the Schiff base ligands coordinated through the azomethine nitrogen and phenolic oxygen. The extraction ability of compounds (1, 3, 4 and 5) were also evaluated in chloroform by using several alkali and transition metal picrates such as Li+, Na+, K+, Cr3+, Mn2+, Ni2+, Cu2+, Zn2+ and Pb2+.  相似文献   

8.
The binding properties of three p-tert-butyldihomooxacalix[4]arene tetraketone derivatives (tert-butyl 2b, adamantyl 2c and phenyl 2d) in the cone conformation and one derivative (methyl 2a) in a partial cone conformation, towards alkali and alkaline earth metal cations have been established by extraction studies of metal picrates from water into dichloromethane, stability constant measurements in methanol and acetonitrile, and by 1H NMR spectrometry. Transport experiments of metal picrates through a dichloromethane membrane were also performed. The results are compared to those obtained with closely-related calix[n]arene derivatives (n = 4 and 5) and discussed in terms of the substituents, size and conformational effects. Methylketone 2a is a poor binder for all the cations studied, due to its partial cone conformation. Ketones 2b, 2c and 2d show high extraction and complexation levels for the alkali cations, with similar profiles and preference for K+ and Na+ (plateau selectivity). Towards alkaline earth cations, these ketones show a strong peak selectivity for Ba2+ in extraction, but a plateau selectivity for Ca2+, Sr2+ and Ba2+ in complexation. The nature of the substituent attached to the ketone function has some influence on their binding properties, with phenylketone 2d being a slightly weaker binder than ketones 2b and 2c. 1H NMR titrations confirm the formation of 1:1 complexes between the ketones and the cations studied, also indicating that they should be located inside the cavity defined by the phenoxy and carbonyl oxygen atoms. Ketones 2b, 2c and 2d show transport rates that do not follow, in general, the same trends observed in extraction and complexation.  相似文献   

9.
The structures of new butadienyl dyes of the benzothiazole series containing the dithia-15-crown-5 (2a) or dithia-18-crown-6 (2b) fragments were established by X-ray diffraction. Complexation of dyes 2a,b with Hg2+, Pb2+, Cd2+, Ag+, Zn2+, and alkaline-earth cations in aqueous-acetonitrile solutions was studied by spectrophotometry. At a high percentage of water in solutions (P w ≈ 50%), these dyes have a very low ability to bind Pb2+ cations (logK < 2) and virtually do not bind Cd2+, Zn2+, and alkaline-earth cations. At the same time, these dyes form stable 1: 1 complexes with Hg2+ and Ag+ cations at all P w. The stability constants of complexes with the Ag+ cation increase with increasing P w because the free energy of hydration of this cation is much lower than the free energy of solvation in acetonitrile. In the P w range from 0 to 75%, the stability constants of the complexes of dyes 2a,b with the Hg2+ cation are larger than those of the corresponding complexes with the Ag+ cation by more than four orders of magnitude. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 90–96, January, 2006.  相似文献   

10.
To determine the metal ion complexing ability of high molecular weight macrocyclic polyamines and polyamides, lipophilic derivatives of azacrown [18]-N6 (hexacyclen) were prepared. Transition and heavy metal picrates, but not alkali and alkaline earth picrates, were extracted from water into chloroform and transported from water through chloroform into a second water phase by the hexa-4-dodecyloxybenzoyl and hexa-3,4-bis-dodecyloxybenzoyl amide derivatives1 and2 and by the hexa-4-dodecyloxybenzyl amine derivative3 of [18]-N6 (hexacyclen). The relative amounts of picrates extracted by hexamine3 from a pH 5 aqueous solution were Cu2+Ag+Pb2+> Hg2+>Zn2+>Co2+>Ni2+Cd2+. Using a pH 7 receiving phase, none of the metal ions were transported rapidly through chloroform, and only Co2+, Cu2+, and Pb2+, were transported rapidly into a pH 11 aqueous phase. The hexamide2, but not hexamide1, extracted significant amounts of the picrates of Cu2+, Ag+, and Hg2+, and transported Cu2+ and Ag+ but not Hg2+.  相似文献   

11.
New thiacalix[4]arenes 2a, 3a, 4 and 5 functionalized with biheterocyclic and azophenyl groups at the lower rim and the upper rim of the macrocycle, respectively, were synthesized and their extraction properties towards Cu2+, Ag+, Ni2+ and Pb2+ studied. The complexation properties of the bithiazolyl receptors 2a, 4 and the bipyridyl receptors 3a, 5 were investigated by fluorescence and UV–visible titrations, respectively. The stoichiometries of the complexes were determined. A stoichiometry of 1:1 was found for the Cu-2a, Ag-3a complexes and 2:1 for the Cu2-4, Ag2-5 complexes as a function of the number of grafted bithiazolyl groups. The association constants for the 1:1 complexes were calculated using the Benesi–Hildebrand plot and by linear regression analysis.  相似文献   

12.
By reacting mono-substituted or 1,3-bi-substituted [2-(p-formylphenyloxy)ethyloxy]-p-tert-butylcalix[4]arene (3 or 4) with hydrazine hydrate in ‘1+2’ or ‘2+2’ condensation mode, novel benzalazine-bridging biscalix[4]arenes 5 and 7 were conveniently obtained in the yields of 76 and 81%, respectively. Condensation of compound 4 and salicylide hydrazone gave a novel calix[4]arene benzalazine derivative 6 in the yield of 85%. The structures and conformations of all new compounds were characterised by elemental analyses, ESI-MS, 1H NMR and 1H–1H COSY techniques. Biscalix[4]arene 7 adopts a symmetrical cone conformation with tube cavity. The liquid–liquid extraction experiment showed that all new hosts possessed excellent complexation abilities towards soft metal cations. Compound 7 exhibited high complexation selectivity towards Ag+. The Ag+/Na+ and Ag+/Hg2+ extraction percentages of host 7 were as high as 73.1 and 54.9, respectively. The UV–vis spectra complexation experiments revealed that the complexation constant of receptor 7 with Ag+ was 1.9 × 105 M? 1 and the 1:1 stoichiometry of receptor 7–Ag+ complex was formed. The 1H NMR spectra complexation experiments suggested that Ag+ was bound in a cavity composed of two benzalazine groups on bridging chains.  相似文献   

13.
Seiichi Inokuma 《Tetrahedron》2006,62(42):10005-10010
Novel crownophanes with two bipyridine moieties (bipyridinocrownophanes 1a and 1b) were conveniently prepared by means of intramolecular [2+2] photocycloaddition of vinylbipyridine derivatives. In the liquid-liquid extraction of heavy metal cations, 1a and 1b exhibited perfect selectivity toward Ag+ with high efficiency. It was found that the ethereal oxygen atoms and the four nitrogen atoms in 1a and 1b acted as ligating sites, according to the high extractability and complexing stability constant for Ag+ compared to those of the corresponding pyridinocrownophanes 4a and 4b. 1H NMR and ESI-MS analyses suggested that the crownophanes formed a 1:1 complexes with the Ag+ ion.  相似文献   

14.
Abstract

The cyclopolymerizations of 1,2:5,6-dianhydro-3,4-di-O-pentyl-D-mannitol (1b) and 1,2:5,6-dianhydro-3,4-di-O-decyl-D-mannitol (1c) were carried out using BF3OEt2 and t-BuOK. All the resulting polymers consisted of cyclic constitutional units, i.e., the extent of cyclization was 100%. The polymer structures for the polymerization with t-BuOK were (1→6)-2,5-anhydro-3,4-di-O-pentyl-D-glucitol (2b) and (1→6)-2,5-anhydro-3,4-di-O-decyl-D-glucitol (2c), whereas those with BF3O-decyl2 comprised 2,5-anhydro-D-glucitols as major units along with other cyclic ones. These polymers were soluble in n-hexane, CHCl3, and THF, but insoluble in water, which differs from the amphiphilic solubility of (1→6)-2,5-anhydro-3,4-di-O-methyl-D-glucitol (2a). The cation-binding properties of 2b and 2c were examined using alkali-metal picrates in order to compare them with those of 2a. The extraction yields for each cation decreased in the order of 2c < 2b < 2a. Every polymer exhibited a similar cation-binding selectivity in the order Cs+ > Rb+ > K+ ? Na+ > Li+. The ratio of K+ and Na+, K+/Na+, was 4.6 for 2a, 5.1 for 2b, and 7.1 for 2c in the increasing order 2a < 2b > 2c.  相似文献   

15.
This article describes extraction properties of mono- (A1A8) and di- (B1B8) substituted azocalix[4]arene analogues. The ionophore solvent extractions of alkaline-earth (Sr2+), basic metal (Pb2+) and transition metal cations (Ag+, Hg+, Hg2+, Co2+, Ni2+, Cu2+, Cr3+) from aqueous phase to organic phase were carried out by azocalix[4]arene derivatives. It has been observed that they show a good extraction behavior toward selected heavy metal (Hg) and toxic metal (Cr), while A4 and B4 prefer Hg+, Hg2+ and Cr3+ among transition metal cations, respectively. The azocalix[4]arenes (A1A8) and (B1B8) are not efficient extractants for all of the selected metal cations, whereas A4 and B4 are selective only for Hg metal cation.  相似文献   

16.
Three novel chromogenic cone azocalix[4]arenes 5ac, which have cavity and the azo groups as metal-binding sites and as coloration sites were synthesized. They were studied by the liquid–liquid extraction of selected metal cations (Sr2+, Ag+, Hg+, Hg2+, Co2+, Ni2+, Cu2+, Zn2+, Cr3+, Al3+). Through examination of the extraction, a novel selectivity of these compounds toward Hg2+ cations has been determined. Besides, it has been also found that azocalix[4]arene 5c is highly sensitive to acid–base titration, which can be detected by the naked eye.  相似文献   

17.
Summary From extraction experiments andg-activity measurements, the extraction constant corresponding to the Ag+(aq) + NaL+(nb)?AgL+(nb) + Na+(aq) equilibrium in the two-phase water-nitrobenzene system (L=valinomycin; aq=aqueous phase, nb=nitrobenzene phase) was evaluated as log Kex(Ag+,NaL+)=-0.6±0.1. The stability constant of the valinomycin-silver complex in nitrobenzene saturated with water was calculated: log bnb(AgL+)=4.6±0.1. The stability constants of complexes of some univalent cations with valinomycin were summarized and discussed.  相似文献   

18.
The complexing properties of four dimalonate and one diester calix[4]arene derivatives toward alkali and alkaline earth cations have been investigated in acetonitrile by means of UV spectrophotometry. Mononuclear complexes have been detected for all the complexesexcept in the case of ligands 4 and 5 with Na+ and Ca2+ where a biligand species (ML2) is present. This later stoichiometry was also confirmed by 1H-NMR and FAB+ MS methods. In the case of ligand 3 and Sr2+we observed the formation of both mono and binuclear species (ML, M2L). Particular selectivities have to be noted from the unique complexation of Na+ and Ba2+ byligand 2 and Rb+ by ligand 3 toward the two series of cations. The complexation is predominantly dependent on the bulkiness of the cavity and the cation size.  相似文献   

19.
The complexation of 13- and 16-memberedazo- and azoxycrowns with metal cations of similarionic diameter (Na+ and Ca2+; and K+,Ba2+, Ag+ and Pb2+) was studied byuv/visible spectroscopic titration in acetonitrile andMeOH. In MeOH the 13-membered azo- and azoxycrowns 1 and 2 are weakly and non-selectively bound tohard cations of similar ionic diameter, but differentcharge (Na+ and Ca2+). At the same time thebinding to the soft cation Ag+ of larger sizethan the macrocycle cavity is considerably stronger.In contrast to solutions in acetonitrile no bindingwith the small Li+ cation was found.The 16-membered azocrowns 3 and 4 alsodiscriminate silver cation in MeOH withlog K = 3.65 ± 0.1 for both compounds.Unexpectedly low bindingwith the hard barium divalent cation of similar size(log K = 1.55 ± 0.4 and 1.95 ± 0.2, respectively)was found for these compounds. Similarly to13-membered compounds no binding with the smallLi+ cation was detected. A reverse order ofselectivity was observed for these crowns inacetonitrile with binding constant for association of3 with Ba2+ (log K 5.3) considerablyhigher than for other cations. The previously observedstrong binding with the smaller Li+ and Na+cations is confirmed.  相似文献   

20.
Three new macrocyclic crown ether ligands containing nitrogen–oxygen donor atoms were designed and synthesized from 1,4-bis(2′-formylphenyl)-1,4-dioxabutane and 4-nitro-o-phenylenediamine. Ion-pair extraction of metal picrates such as Ag+, Hg2+, Cd2+, Zn2+, Cu2+, Ni2+, Mn2+, Co2+, and Pb2+ from aqueous phase to the organic phase was carried out using the novel ligands. The solvent effect over the metal picrate extractions was investigated at 25 ± 0.1 °C by using UV–visible spectrometry. The extractability and the values of the extraction constants (log Kex) were determined for the extracted complexes.  相似文献   

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