共查询到20条相似文献,搜索用时 609 毫秒
1.
Novel monoazacryptand-type fluorescent chemosensors, (derived from an 18-crown-6) and (derived from a 15-crown-5) both with a pyrene ring as their photoresponsive moiety, were synthesized. Their fluorescence properties for alkali metal and alkaline earth metal cations in water were then examined. The detection of metal cations was accomplished by a change in the fluorescence intensity of the host compounds, based on a photoinduced electron transfer (PET) mechanism. In aqueous solution, showed little fluorescence upon the addition of Ba2+ because of the very weak complexation with Ba2+, but the presence of micelles of polyoxyethylene(10) isooctylphenyl ether (Triton X-100) enabled to show highly sensitive and selective Ba2+ detection among alkali metal and alkaline earth metal cations. With respect to the selective fluorescent detection of important metal cations (Na+, K+, Mg2+, Ca2+) relevant to living organisms, was found to detect K+ with high selectivity in aqueous micellar solutions of polyoxyethylene(20) sorbitan monostearate (Tween-60). The selectivity for metal cations was mainly dependent on the goodness of fit of the host cavity and the metal cation size. In the presence of anionic surfactants, detected alkaline earth metal cations more effectively than alkali metal cations. 相似文献
2.
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
3.
Studies on 16-Membered Azothia- and Azoxythiacrown Ethers as Ion Carriers in Ion Selective Membranes
Jolanta Szczygelska-Tao Jan F. Biernat Łukasz Górski Elżbieta Malinowska 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(1-2):167-171
16-Membered azothia- and azoxythiacrown ethers have been studied as ion carriers in ion-selective membranes. Their selectivities towards alkali, alkaline earth, transition and heavy metal cations were evaluated. The complex formation constants for these compounds with chosen cations have been determined using segmented sandwich membranes method. 相似文献
4.
M. I. Naumova N. V. Kuratieva D. Yu. Naumov N. V. Podberezskaya 《Journal of Structural Chemistry》2004,45(1):107-113
Crystals of anhydrous K, Rb, and Cs hypophosphites have been obtained. The structures of these compounds were determined by X-ray diffraction analysis. The structure in general is a packing of layers of metal cations and hypophosphite anions coordinated to them. In all compounds, the hypophosphite anion performs the function of a bridge between four cations in a layer. Each oxygen atom is linked to two cations. The compounds RbH2PO2 and CsH2PO2 are isostructural. 相似文献
5.
A. R Hajipour S. Habibi A. E. Ruoho 《Journal of inclusion phenomena and macrocyclic chemistry》2011,69(1-2):107-117
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
6.
Thermal decomposition of potassium chlorate in the presence of various additives is studied using thermogravimetric analysis and differential thermal analysis. Catalytic effects of metal oxides with comparable surface areas are compared, and the catalytic effects of a number of nonoxide additives are also studied. The nonoxide additives show catalytic activities similar to the corresponding metal oxides. Metal cations and their electron configurations determine the catalytic activity of various compounds. Metal cations with partially filledd shells have the highest activity, transition metal cations with completely emptyd orbitals are moderated active, and metal cations with completely filledd shells or noble gas configurations have minimum activity. 相似文献
7.
Characterizing Polyoxovanadate-Alkoxide Clusters Using Vanadium K-Edge X-Ray Absorption Spectroscopy
Rachel L. Meyer Samuel M. Greer Anastasia V. Blake Samantha K. Cary Alexander S. Ditter Scott R. Daly Feng Li Stosh A. Kozimor Ellen M. Matson Veronika Mocko Gerald T. Seidler Benjamin W. Stein Samuel D. Weinstein 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1592-1597
A number of technologies would benefit from developing inorganic compounds and materials with specific electronic and magnetic exchange properties. Unfortunately, designing compounds with these properties is difficult because metal⋅⋅⋅metal coupling schemes are hard to predict and control. Fully characterizing communication between metals in existing compounds that exhibit interesting properties could provide valuable insight and advance those predictive capabilities. One such class of molecules are the series of Lindqvist iron-functionalized and hexavanadium polyoxovanadate-alkoxide clusters, which we characterized here using V K-edge X-ray absorption spectroscopy. Substantial changes in the pre-edge peak intensities were observed that tracked with the V 3d-electron count. The data also suggested substantial delocalization between the vanadium cations. Meanwhile, the FeIII cations were electronically isolated from the polyoxovanadate core. 相似文献
8.
Studies on the Synthesis and Complexing Behavior of Crown Ethers with External Coordination Center 总被引:1,自引:0,他引:1
Jing Chao TAO Yang Jie WU* Shang Jie XU Da Peng ZOU Department of Chemistry Zhengzhou University Zhengzhou 《中国化学快报》2001,(6)
Ligands capable of positioning two or more very different metal cations, like transition metal and alkali or alkaline earth metal cations, have been described recently1-3. Reinhoudt et al. have synthesized a number of ligands with the cavity for transition metal cations as well as the cavity for alkali metal cations and the corresponding comlexes with different kinds of metal ions4,5. It was anticipated that co-complexation of a hard cation closing to the complexed transition metal cation woul… 相似文献
9.
Stephane Dumas Ivo Grabchev Polia Stoikova Jerome Chauvin Jean-Marc Chovelon 《Journal of photochemistry and photobiology. A, Chemistry》2009,201(2-3):237-242
The paper reports on the synthesis of two new benzanthron derivatives with intense yellow-orange fluorescence and their copolymers with styrene. The photophysical characteristics of the new low and high molecular weight fluorescent compounds have been studied in organic solvents of different polarity. The effect of the chemical nature of the C-3 substituent on the photophysical properties of the new dyes is discussed. The complexes formed between the benzanthron fluorophores and metal cations in solution have been studied with regard to potential applications as fluorescent sensors for metal ion contamination. The results show that the C-3 substituent determines a selective response to the presence of Cu2+ cations. In the case of copolymers the effect of the metal cations on the fluorescence intensity is negligible. 相似文献
10.
Ali A. Abdel Hafez Ibrahim M. A. Awad 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):381-389
Abstract Some new sulphonyl-N-heterocyclo-8-hydroxy quinolines have been synthesised by the reaction of 8-hydroxyquinoline-5-sulphonyl hydrazide with different active methylene compounds. The pyrazole, pyrazoline, pyrazolidine and pyridazine derivatives were reacted with some metal cations to give the corresponding chelates. All synthesized compounds have been screened in vitro for their biological activities. 相似文献
11.
Jerald S. Bradshaw Peter Huszthy Reed M. Izatt 《Journal of heterocyclic chemistry》1986,23(6):1673-1676
A new series of macrocyclic ligands containing the dialkylhydrogenphosphate moiety is reported. These compounds were prepared by reacting phosphorus oxychloride with the appropriate oligoethylene glycol followed by a hydrolysis step. One of these new macrocyclic compounds transported the alkali metal cations as well as lead, zinc and silver ions. 相似文献
12.
S. E. Solovieva M. Grüner A. O. Omran A. T. Gubaidullin I. A. Litvinov W. D. Habicher I. S. Antipin A. I. Konovalov 《Russian Chemical Bulletin》2005,54(9):2104-2112
The interaction of p-tert-butylthiacalix[4]arene with N,N-diethylchloroacetamide was studied in the presence of alkali metal carbonates in acetone. Three stereoisomers, viz., cone, partial cone, and 1,3-alternate, of the tetraamide derivative of thiacalixarene substituted at the lower rim were
synthesized selectively using the template effect of alkali metal cations, as well as a complex of the 1,3-alternate stereoisomer
with potassium chloride. The structures of the compounds synthesized were studied by 2D NMR spectroscopy. A high extraction
ability of the compounds toward alkali metal cations was demonstrated.
Dedicated to Academician A. L. Buchachenko on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2041–2049, September, 2005. 相似文献
13.
Reed M. Izatt Gypzy C. Lindh Jan F. Biernat Maria Bochenska Ronald L. Bruening Jerald S. Bradshaw James J. Christensen 《Journal of inclusion phenomena and macrocyclic chemistry》1989,7(5):487-499
The transport of alkali metal cations by several macrocycles possessing two sulfonamide groups as a part of an 18-, 20-, or 21-membered macroring has been studied. Some of these compounds were found to be more effective transport agents than the proton-ionizable pyridone- and triazole-containing crown ethers reported previously. The factors affecting transport, such as ring size, source and receiving phase pH, and the nature of the groups attached to the sulfonamide nitrogen atoms were examined. Also, extraction experiments by some of the ligands were performed. The behavior of sulfonamide type crowns in single and competitive transport of the alkali metal cations is explained. The mechanism of transport appears to be complex. Transport of one or two cations per molecule of the disulfonamide carriers occurs. Complexation of these cations appears to occur both within and outside the macrocycle cavity. Our results also suggest that kinetic factors may play a significant role in transport rates and selectivities.Deceased: September 5, 1987. 相似文献
14.
Fafu Yang Ziyu Jiao Zhisheng Huang Jianwei Xie Hongyu Guo 《Journal of inclusion phenomena and macrocyclic chemistry》2012,74(1-4):257-263
By formylation of calix[4]-1,3-aza-crown in hexamethylenetetramine/trifluoroacetic acid system, the first formylated calix[4]-aza-crown derivative 6 was synthesized in yield of 61%. Reacting compound 6 with salicyloyl hydrazine, 2,4-dinitrophenyl hydrazine, nicotinyl hydrazine or phenyl thiosemicarbazide afforded four novel calix[4]crown hydrazone derivatives 7a–d in yields of 70–90%. By condensating compound 6 with series of bifunctional reagents, the novel mono-bridged biscalix[4]-aza-crown hydrazone derivatives 8a–c were prepared in high yields. The extraction experiments showed that all new compounds were good receptors for metal cations, especially, for soft metal cations. The extraction results suggested that the hydrazone groups produced favorable influences for binding soft cations. The two calix[4]arene units in compounds 8a–c could bind metal cations concurrently. 相似文献
15.
The synthesis and characterization of new tetramethoxy resorcinarene bis-crown ethers BC4 and BC5 are described. The complexation properties of the compounds toward alkali metal cations were studied by 1H NMR spectroscopy and X-ray crystallography, which revealed that BC5 can accommodate two cations simultaneously inside the crown pockets formed by the crown ether bridges and the resorcinarene skeleton. [reaction: see text]. 相似文献
16.
Fafu Yang Zhisheng Huang Jianwei Xie Xiaoyi Zhang Hongyu Guo 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(1-2):11-18
Four novel calix[4]arene hydrazone-based receptors 3a?Cd were prepared in yields of 69?C87% by condensating formylated calix[4]arene ester (2) with salicylyl hydrazine, 2,4-dinitrophenyl hydrazine, nicotinyl hydrazine or phenyl thiosemicarhazide, respectively. New compounds were characterized through elemental analysis, IR, ESI?CMS, 1H NMR studies. Compounds 3a?Cd containing two binding sites had the complexation abilities for hard and soft cations concurrently. The noncompetitive extracting experiments showed compounds 3a?Cd were excellent receptors for hard and soft metal cations. The competitive extracting experiments exhibited the cooperative complexation in binding hard and soft metal cations and compound 3a possessed outstanding selectivity for Na+ and Hg2+. The IR spectra of compound 3a before and after complexation revealed that the soft metal cation was binded in the cavity composed of hydrazone groups and azo groups at the upper rims of calix[4]arene units and hard metal cations was binded in cavity composed of ester groups and phenolic hydroxyl groups at the lower rims of calix[4]arene units. 相似文献
17.
Daniel Ammann Ren Bissig Marc Güggi Ern Pretsch Wilhelm Simon Irving J. Borowitz Louis Weiss 《Helvetica chimica acta》1975,58(6):1535-1548
The preparation of a series of non-cyclic, uncharged ligands able to selectively complex alkali and alkaline earth metal cations is described. These molecules are designed to be used as carriers for cations through membranes. Some of the compounds show high Ca2+ and Na+ selectivity, respectively, in liquid membrane electrodes. 相似文献
18.
Sadatoshi Akabori Yoichi Habata Hiroyuki Muneguni Masaru Sato 《Tetrahedron letters》1984,25(19):1991-1994
Synthesis and extraction ability of macrocyclic compounds containing ruthenocene as an integral part of the macrocyclic skelton are reported. Also, the complexes of the 1,n-dithiaoxa[n]ruthenocenophanes with transition metal cations were isolated. 相似文献
19.
20.
A. B. Smolentsev V. V. Korolev E. M. Glebov V. P. Grivin V. F. Plyusnin A. I. Kruppa A. V. Chebun’kova S. V. Paramonov O. A. Fedorova V. Lokshin A. Samat 《Kinetics and Catalysis》2012,53(1):54-64
The photochemistry and complexation with alkaline-earth metal cations of two crown-containing naphthopyrans and their crownless analogues are reported. Two types of photoreactions occur in the system, namely, the reversible formation of the open form, which is responsible for the photochromism of these compounds, and the geometric isomerization of the closed form. The photochromic properties (UV spectrum and lifetime) of the naphthopyrans do not change upon complexation with metal cations. This is explained by the specific features of the structure of the open form and by the kinetic parameters of the processes. 相似文献