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1.
New Type of Lariat Ethers: Synthesis and Cation Binding Ability of Phosphonoalkyl-Azacrown Ethers 总被引:2,自引:0,他引:2
György Keglevich Tibor Novák Péter Bakó Kálmán újszászy Krisztina Ludányi Klára Tóth László Tõke 《Journal of inclusion phenomena and macrocyclic chemistry》1999,34(3):299-309
The synthesis of azacrown ethers with phosphonoalkyl side chains of two to five carbon atoms ( 3–8, 10), potentially useful as a new type of cation binding agent, is described. Introduction of the phosphonoalkyl moiety into the parent monoaza-15-crown-5 ( 1) decreases the cation extraction ability, but results in an increase in the selectivity towards the cations examined. The effect of the phosphonoalkyl-azacrown ethers on the properties of membranes used in ion-selective electrodes is also reported. 相似文献
2.
Alan P. Marchand Anna Hazlewood Zilin Huang Satish Kumar Vadlakonda John-David R. Rocha Trevor D. Power Kata Mlinarić-Majerski Lada Klaić Goran Kragol Jeffrey C. Bryan 《Structural chemistry》2003,14(3):279-288
Bis-cage-annulated 18-crown-6 and 20-crown-6 macrocyclic ethers (i.e., 1 and 2, respectively) have been synthesized, and their alkali metal picrate extraction profiles have been determined. Host system 1 proved to be a significantly more avid alkali metal cation complexant than 2 and somewhat more avid than 18-crown-6. Both 1 and 18-crown-6 display modest selectivity toward K+ and Rb+. A stable host–guest complex was prepared by slow evaporation of a CH2Cl2–hexane solution of an equimolar mixture of 2 and potassium picrate. The X-ray crystal structure of this complex reveals that picrate anion functions as a bidentate ligand therein. The gas-phase interaction energy between the 2 K+ complex and picrate anion was calculated to be ca. –64.9 kcal mol–1, thereby indicating that participation of picrate anion as an additional bidentate ligand results in significant stabilization of complex 10. 相似文献
3.
Zhijun Zhang Haoyun An Xiaodong Ma Xingtang Zhang Yangjie Wu Ziquiang Zhu 《Journal of inclusion phenomena and macrocyclic chemistry》1992,13(4):329-335
4-Octadecanoylbenzo-15-crown-5 (I) and four 4-alkylbenzo-15-crown-5 ligands [4-XB15C5 where X =n-C18H37 (II), X =n-C16H33 (III), X =n-C14H29 (IV), and X =n-C12H25 (V)] have been synthesized. The -A isotherms ofI andII were systematically investigated. The results indicated that the Langmuir-Blodgett (LB) films have high stability where the ratios ofI/SA andII/SA were 1 : 1 and 1 : 10, respectively, with a 6.2 pH subphase. The LB films of the crown ethers were deposited onto graphite electrodes pretreated by immersing them in liquid wax. The peak current reached the maximum value when the electrode surface was modified with five layers of the amphiphilic crown ethers. 相似文献
4.
A. V. Podolskii T. G. Khonina O. V. Koryakova M. I. Kodess 《Russian Chemical Bulletin》1993,42(6):1052-1055
Crown ethers form strong proton-acceptor complexes with CF3COOH or C4F9COOH that undergo thermal decarboxylation at 200–260 °C which results in 60–80% of CF3H or C4F9H (including up to 20 % of a mixture of C4F8). Critical parameters of the process were determined in relation to the temperature and amount of crown ether. The relative activities of different crown ethers in decarboxylation were also established. A scheme is proposed that explains the effect of the structure of crown ethers on this reaction. The data obtained substantiate the view that the topological correspondence concept is insufficient to explain the ability of crown ethers to form complexes with cations.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1098–1101, June, 1993. 相似文献
5.
Hans-Jurgen Buschmann 《Journal of solution chemistry》1986,15(6):453-461
The complexation of alkaline-earth cations by different crown ethers, azacrown ethers, and cryptands has been studied in methanol solutions by means of calorimetric and potentiometric titrations. The smallest monocyclic ligands examined form 21 complexes (ratio of ligand to cation) with cations which are too large to fit into the ligand cavity. With the smallest cryptand, only Sr2+ and Ba2+ ions are able to form exclusive complexes. In the case of the reaction of cryptand (211) with Ca2+, a separate estimation of stability constants for the formation of exclusive and inclusive complexes was possible for the first time. Higher values for stability constants are found for the reaction of alkaline-earth cations with cryptands compared to the reaction with alkali ions. This increase is only caused by favorable entropic contributions. 相似文献
6.
The relative thermodynamic stabilities of a number of isomeric allyl vinyl and propenyl vinyl ethers were determined by chemical equilibration in DMSO solution with KOBu-t as catalyst. From the temperature dependence of the values of the equilibrium constant the parameters G
m
, H
m
and S
m
of isomerization at 298.15 K were evaluated. Propenyl vinyl ethers, owing to their low enthalpy contents, are much more stable than the isomeric allyl vinyl ethers. It appears that in the parent propenyl vinyl ether, the Me group attached to C- of the divinyl ether skeleton has a strong stabilizing effect, comparable to that of alkyl groups in ordinary olefins, on the unsaturated system. In more heavily alkyl-substituted divinyl ethers, however, the stabilizing effects of alkyl groups are less prominent, being comparable to the low stabilization energies of alkyl groups in vinyl ethers, and depend moreover, on the pattern of substitution. 相似文献
7.
E. Luboch A. A. Dvorkin Yu. A. Simonov 《Journal of inclusion phenomena and macrocyclic chemistry》1994,20(4):335-351
Lipophilic derivatives of benzo-12-crown-4 and naphtho-12-crown-4 have been synthesized. The behavior of the parent compounds and their derivatives in membrane ion-selective electrodes have been studied. Selectivity changes have been observed with the rise in lipophilicity. Crystal structures of the NaI and KI complexes of benzo-12-crown-4 (1 and2) have been determined by X-ray analysis. The alkali metal and iodide ions are in direct contact in2 but not in1. Compound1 [Na(benzo-12-crown-4)2]·I is triclinic, witha=13.368(8),b=10.727(7),c=10.325(4) Å; =73.56(4),=77.73(4), =108.70(5)°;Z=2, space group is
. Compound2 [K(benzo-12-crown-4)2·I] is monoclinic, witha=15.807(8),b=12.043(4),c=15.601(6) Å,=117.74(3)°;Z=4, space groupC2/c. In both compounds the cations interact with all oxygen atoms of two crown ether molecules. Correlation of the crystal structures and behavior of the crown ethers in ion-selective membrane electrodes is discussed.
Supplementary Data related to this article have been deposited with the British Library as Supplementary Publication No. 82185 (15 pages). 相似文献
8.
Péter Bakó Tibor Bakó Katalin Bisztray Áron Szöllősy Kornél Nagy László Tőke 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):247-251
New chiral monoaza-15-crown-5 ethers have been synthesised from 1,2:5,6-di-O-isopropylidene-D-mannitol. The substituent at the nitrogen atom has a major influence on the cation extraction ability of the azacrown. These sugar-based crown ethers show asymmetric induction as chiral phase transfer catalysts in the Michael addition of 2-nitropropane to chalcone (67% ee). 相似文献
9.
Yurii A. Simonov Alexandr A. Dvorkin Marina S. Fonari Tadeush I. Malinowski Elżbieta Luboch Andrzej Cygan Jan F. Biernat Edward V. Ganin Yurii A. Popkov 《Journal of inclusion phenomena and macrocyclic chemistry》1993,15(1):79-89
The crystal structures of two 12-membered crown ethers, benzo-12-crown-4 (1) and naphtho-12-crown-4 (2), have been determined by X-ray analysis. Both structures are molecular. Compound1 is monoclonic,P21/b,a=8.466(3),b=8.019(3),c=33.590(10) Å, =90.99(3)o. The unit cell contains two crystallographically independent molecules of1 with similar conformations. Compound2 is also monoclinic,P21/a,a=24.148(8),b=14.535(4),c=7.987(5) Å, =102.87(2)o. Two independent molecules in the unit cell have significantly different conformations.
Supplementary data relating to this publication have been deposited with the British Library as Supplementary Publication No. SUP 82145 (19 pages). 相似文献
10.
11.
Tibor Novák Péter Bakó Timea Imre György Keglevich András Dobó László Tõke 《Journal of inclusion phenomena and macrocyclic chemistry》2000,38(1-4):435-443
Azacrown ethers with phosphonoalkyl-and phosphinoylalkyl side chains of two to five carbonatoms (2–4, 7 and 5–6, 8,respectively) were synthesized in acceptable yields.The cation binding ability of the new lariat etherswas evaluated by the picrate extraction method.Introduction of the P-functionalised N-substituentresulted in a decrease in the cation extractionability in most cases, but the discrimination betweenthe cations examined was, in some instances,significantly increased. 相似文献
12.
V. K. Ahluwalia Ranjna Gupta Nimmi Rani 《Monatshefte für Chemie / Chemical Monthly》1984,115(3):327-332
The reaction of 7-hydroxy-4-methoxy- (1a), 7-hydroxy-4,5-dimethoxy-(1b) and 5-hydroxy-4,7-dimethoxy (1c) -2H-1-benzopyran-2-ones with prenyl bromide in acetone in the presence of anhydrous potassium carbonate gave the corresponding prenyloxycoumarins1d,1e, and1f. The prenyloxy coumarins1d,1e,1f onClaisen migration by refluxing inN,N-dimethyl aniline gave the corresponding 4,4,5-trimethyl-dihydrofuranocoumarins2a,2b, and3. However, the reaction of1a,1b, and1c with 3-chloro-3-methyl-but-1-yne in acetone in presence of potassium carbonate and potassium iodide gave the corresponding propargyl ethers1g,1h,1i, which on refluxing inN,N-dimethyl aniline gave the corresponding 2,2-dimethylchromenopyrans4a,4b, and5. These can also be obtained directly if the reaction is carried out in the presence of dioxan.
Die Reaktion von 4-Methoxycumarinen mit Prenylbromid: Synthese von 4,4,5-Trimethyl-dihydro-furanocumarinen und 2,2-Dimethylchromenopyranen
Zusammenfassung Die Reaktion von 7-Hydroxy-4-methoxy-(1a), 7-Hydroxy-4,5-dimethoxy-(1b) und 5-Hydroxy-4,7-dimethoxy-2H-1-benzopyran-2-onen (1c) mit Prenylbromid in Aceton in der Gegenwart von wasserfreiem Kaliumcarbonat ergab die entsprechenden Prenylcumarine1d,1e und1f. Diese ergaben durchClaisen-Wanderung bei Rückfluß inN,N-Dimethylanilin die entsprechenden 4,4,5-Trimethyldihydrofuranocumarine2a,2b und3. Die Reaktion von1a,1b und1c mit 3-Chlor-3-methyl-1-butin in Aceton in Gegenwart von wasserfreiem Kaliumcarbonat und Kaliumjodid ergab die entsprechenden Propargylether1g,1h und1i, die ihrerseits bei Rückfluß inN,N-Dimethylanilin die jeweiligen 2,2-Dimethylchromenopyrane4a,4b und5 ergaben. Letztere können auch direkt erhalten werden, wenn die Reaktion in Gegenwart von Dioxan durchgeführt wird.相似文献
13.
A. Skwierawska E. Luboch J.F. Biernat V. Ch. Kravtsov Yu. A. Simonov A. A. Dvorkin V. K. Bel'skii 《Journal of inclusion phenomena and macrocyclic chemistry》1998,31(1):71-86
16-Membered dibenzoazo- and dibenzoazoxycrown ethers have been synthesized. The Z and E isomers of the azocrown compound have been separated and the geometry of the –N=N– and –-N(O)=N–- groups determined. Potassium iodide complexes of the azo- and azoxycrown ethers were obtained and their structures were determined by the X-ray method. The crystal of the azocrown ether complex is triclinic, space group P¯1, a = 21.071(5), b = 12.112(4), c = 8.757(2) Å = 81.28(2), = 84.66(2), = 107.49(2)°. The azoxycrown ether complex is monoclinic, space group C2/c, a = 15.648(3), b = 19.597(4), c = 14.651(3) Å; = 111.30(3). 相似文献
14.
Péter Bakó László Fenichel László Tôke 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(4):321-330
Crown ethers1 and4 of the 18-crown-6 type containing two glucose units have been oxidised by KMnO4 into mono- and dicarboxylic acid derivatives (5 and11), and derivatives with different lipophilicities of the above crown ethers, namely the acetyl, benzyl and butyl derivatives (8–10, 13, 14) and methyl esters (6 and12) have been synthesizedThe association constants (K
a) with Li, Na, K and NH4 cations measured in CHCl3 indicate that complexing ability increases on introduction of carboxy groups, and selectivity changes in favour of the Na cation. These compounds were able to transport alkyl-ammonium salts through a CHCl3 liquid membrane, displaying, however, no chiral recognition ability. 相似文献
15.
Mehdi Bakavoli Mohammad Rahimizadeh Esmaeel Rezaei-Seresht Majid Mokaber Esfahani Parisa Ziaee 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2152-2158
The synthesis of some novel crown and thiacrown ethers via the reaction of 2,3-bis(4-hydroxyphenyl) or 2,3-bis(4-mercaptophenyl)quinoxalines and pyridopyridazine with diethylene and triethylene glycol ditosylate is described. The complexing ability of compounds 5b and 5h, as the representatives of both groups of compounds, with alkali and alkali earth metal cations were measured by the solvent extraction method. The results showed that crown ether 5b comparatively had more affinity towards the Mg2+ cation, while thiacrown ether 5h had greater affinity towards the Ca2+ cation. 相似文献
16.
Roman Luboradzki Janusz Lipowski Yurii A. Simonov Marina S. Fonari Edward V. Ganin Arkadii A. Yavolovskii 《Journal of inclusion phenomena and macrocyclic chemistry》2001,40(1-2):59-65
The X-ray crystal structures of two closely related molecular complexes of 15-crown-5 and benzo-15-crown-5 with 3,4-diamino-1,2,5-oxadiazole are reported (I and II). Both complexes are of 1:1 stoichiometry with the host–guest alternation in the infinitechains formed due to the unsymmetrical H-bonding patterns between the components. Crystals of I are monoclinic, P21/c, a = 7.856(3), b = 12.994(1), c = 16.033(1) , = 94.79(2)°, Z = 4, final R-factor is 0.0488. Crystals of II are orthorhombic, P212121, a = 8.260(4), b = 15.692(5),c = 13.955(7) , Z = 4, final R-factor is 0.0522. 相似文献
17.
E. A. El'perina M. I. Struchkova M. I. Serkebaev E. P. Serebryakov 《Russian Chemical Bulletin》1993,42(4):751-754
Starting from 1,32,4-di-O-ethylidene-D-glucitol (1), two regioisomeric monoaza-18-crown-6 ethers withC
2 symmetry were synthesized. A simple route was suggested for the preparation of a diol that is a convenient intermediate for the synthesis of chiral aza-crown ethers from diol1.For Part 7, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 782–785, April, 1993. 相似文献
18.
Pedro Bernal Albert Bunn Jennifer Logan Jennifer McCluan 《Journal of solution chemistry》2000,29(7):651-665
Apparent molar volumes and adiabatic compressibilities of 18-crown-6,15-crown-5, 12-crown-4, tetraglyme, and triglyme were measured at 15, 25, and40°C. Apparent molar expansibilities andK
o
Tvalues were also determined.The contribution of the -CH2CH2O- group to the limiting partial molar volumesand compressibilities of cyclic and open-chain ethers are compared. It isconcluded, on the basis of the compressibility results, that there is a subtle differencebetween the hydration of the ethene-oxide group in cyclic and open-chain ethers. 相似文献
19.
Unlike linear extracting agents, in the extraction of metal salts from aqueous solutions of inorganic acids with crown ethers, the inclusion compounds, whose composition depends on several external and internal factors, go to the organic phase. The study of the molecular structure of the formed complexes by X-ray diffraction analysis showed that adducts of crown ethers with inorganic acids are host–guest complexes in which the hydroxonium ion is in the polyether macrocycle cavity. When the aqueous phase contains metal ions capable of displacing the hydroxonium ions from the macrocycle (K+, Pb2+, Hg2+, Sr2+, NH4
+), complexes containing metal cations as the guest in the macrocycle cavity, according to X-ray diffraction data, go to the organic phase. In addition, metals forming ionic associates (AuCl4
-, FeCl4
-, GaCl4
-) in an aqueous solution are extracted with crown ethers in accordance with the anion-exchange mechanism. A system in which traces of metals in the 2 M HNO3 +5 M HCl mixture serve as the aqueous phase was proposed for estimation of the general extraction ability of crown ethers. Such a system can be used for metal extraction via any possible mechanism. The stereochemical peculiarities of the extraction ability of crown ethers (compared to linear molecules) can be used for selective extraction and separation of metals. 相似文献
20.
Cationic ether lipids containing nitrogenous heterocyclic bases as the positively charged groups were synthesized. Treatment of methylthiomethyl ethers of dialkylglycerols with bromine afforded highly reactive -bromo ethers. These products reacted with various nucleophilic reagents giving rise to a series of cationic alkylglycerols. 相似文献