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1.
A novel series of benzo crown ether (dibenzo 18-crown-6 ether, benzo 18-crown-6 ether, and benzo 15-crown-5 ether) functionalized enamines derivatives from amino benzo crown ether (4-amino dibenzo 18-crown-6 ether, 4-amino benzo 18-crown-6 ether, 4-amino benzo 15-crown-5 ether) and substituted 3-(dimethylamino)-1-phenylprop-2-en-1-one compounds have been synthesized. All the synthesized compounds were characterized by infrared, 1H NMR, 13C NMR, distortionless enhancement polarization transfer, and mass and elemental analysis techniques. The cation recognition property for benzo crown ether enamine 8a was studied by absorption and fluorescence spectroscopy.  相似文献   

2.
The alkali metal- and ammonium picrate extracting ability of d-glucose- and d-mannose-based 15-crown-5 ethers and related lariat ethers was investigated in dichloromethane – water system. A heteroatom was waried in the crown ether containing a 4,6-O-benzylidene-α-d-glucopyranoside unit 6, (X=O), 2 (X=S) and 8a (X=NH). Extracting ability of the latter species (8a) was excellent (97–99%) in regard of all cations (Li+, Na+, K+, Rb+, Cs+ and NH4+) examined, it was not, howewer, selective. Introduction of a side arm on the nitrogen atom of 8a decreased the extracting ability, but increased the selectivity. In this series of compounds (8bf, 4), 4 with a pyridylethyl substituent allowed the extraction of sodium picrate in 72%. The glucose-based macrocycles 8a, 8e and 8f formed a stronger complex with the cations examined than the mannose-based analogues 9a, 9e and 9f, that can be explained by the all-gauche conformation of the former ones. It was pointed out that in the case of crowns with tertiary amine moieties, the basicity increases the quantity of the picrates extracted. According to complex forming measurements by FAB-MS, the best sodium ion selectivity was achieved by the γ-hydroxypropyl substituted lariat ether (8e). Possible structures of the complexes formed by the two types of monosacharides with sodium cation were evaluated by molecule modelling calculations.  相似文献   

3.
Lokman Torun 《Tetrahedron》2005,61(35):8345-8350
Lariat ether carboxylic acids of structure CECH2OCH2C6H4-2-CO2H with crown ether (CE) ring sizes of 12-crown-4, 15-crown-5 and 18-crown-6 are prepared and converted into alkali metal-lariat ether carboxylate complexes. Absorptions for the diastereotopic benzylic protons in the 1H NMR spectra of the complexes in CDCl3 are utilized to probe the extent of side arm interaction with the crown ether-complexed metal ion as a function of the crown ether ring size and identity of the alkali metal cation.  相似文献   

4.
13-Membered azothia- and azoxythiacrown ethers have been applied as ion carriers in ion-selective membrane electrodes. Their sensitivity and selectivity were studied towards alkali, alkaline earth, transition and heavy metal cations. It was found that membranes doped with the azoxythiacrown ether (A) show higher affinity towards Pb2+ than Cu2+ (log KCu,Pb pot = 1.7), whereas membranes with the azothiacrown ether (B) are more selective towards Cu2+ than Pb2+ (log KCu,Pb pot = -2.4). The discrimination of alkali and alkaline earth cations was found to be greater for B than for A. Electrodes with both ionophores suffered from strong interference by Ag+ and Hg2+. The relation between the carrier structure and electrode properties has been discussed.  相似文献   

5.
本文报道了一种合成硫杂冠醚聚合物的新方法。以聚(2′-氯乙基-2,3-环硫丙基醚)为预聚物与二巯基化合物通过大分子反应直接环化,一步法合成了四种以聚硫醚为主链的新型硫杂冠醚聚合物(PD1-PD4)。并测定了它们对Ag~+、Au~(3+)、Pd~(2+)、Pt~(4+)、Cu~(2+)、Hg~(2+)、Zn~(2+)、Cd~(2+)、Pb~(2+)、Mg~(2+)、K~+、Ns~+等金属离子的络合性能。结果表明:它们除不络合K~+、Na~+、Mg~(2+)、Pb~(2+)外,对其它八种离子有不同程度的络合,其中对Ag~+、Au~(3+)、Pd~(2+)等贵金属离子的络合容量较高。  相似文献   

6.
The novel unique structures of bis-crown ethers were successfully synthesized from tri (propylene glycol) di-acrylate with amino- and aza-crown ethers through Michael addition. The crown ethers contained the primary and the secondary amine group such as 2-aminomethyl crown ethers, 4-aminobenzo crown ethers and 1-aza crown ethers. The newly synthesized bis-crown ethers were characterized by elemental analyses, IR, 1H NMR, 13C NMR, mass spectrum, respectively. The newly synthesized host compounds of bis-crown ethers showed complex ability with various sizes of alkali metal cations such as Na+, K+, Rb+ and Cs+. The complexation behavior was examined by 1H NMR spectroscopy and UV spectrometry.  相似文献   

7.
 本文报道了一种合成硫杂冠醚聚合物的新方法。以聚(2′-氯乙基-2,3-环硫丙基醚)为预聚物与二巯基化合物通过大分子反应直接环化,一步法合成了四种以聚硫醚为主链的新型硫杂冠醚聚合物(PD1-PD4)。并测定了它们对Ag+、Au3+)、Pd2+、Pt4+、Cu2+、Hg2+、Zn2+、Cd2+、Pb2+、Mg2+、K+、Ns+等金属离子的络合性能。结果表明:它们除不络合K+、Na+、Mg2+、Pb2+外,对其它八种离子有不同程度的络合,其中对Ag+、Au3+、Pd2+等贵金属离子的络合容量较高。  相似文献   

8.
Six catalysts MnClL1–MnClL6, containing two crown ether rings, were synthesised and characterised by IR spectroscopy and CHN microanalysis. A combination of Oxone, as oxidant, and these catalysts was used for the oxidation of cyclohexene and cyclooctene. Among the prepared catalysts, MnClL3 and MnClL4 exhibited the best catalytic efficiency. Catalysts MnClL1, MnClL2 and MnClL6 showed a moderate efficiency and MnClL1 showed the lowest efficiency. Comparison of MmclL1–MnClL4 and MnClL6 containing crown ether rings with an identical mixture of uncrowned complex MnClL7 [manganese N,N′-bis(salicylidene)ethylenediamine chloride] and crown ether 2 (4′-hydroxybenzo-15-crown-5), revealed a more important role for the crown ether than increasing solubility of Oxone in the organic phase. The effect on reaction times and chemical yields of temperature, pyridine as the axial base, and different alkali metal salts was also investigated.  相似文献   

9.
A new calixcrown‐6 oligomer 5 was synthesized by reacting a 1,3‐distal di‐amino derivative of cone p‐tert‐butylcalix[4]crown‐6 with malonyl dichloride. Extraction studies with precursor monomers 2 and 3 and oligomer 5 showed differences in their metal cation extraction behavior and selectivity. Precursors monomers 2 and 3 were selective for Hg2+; whereas, oligomer 5 showed high affinity towards both alkali (Li+, Na+, K+, and Cs+) and heavy metal cations (Cu2+, Cd2+, Hg2+ and Pb2+).  相似文献   

10.
Four cone calix[4]arene-1,2-crown ethers each with two ionisable side arms containing dansyl groups are synthesised. The crown ether ring on the lower rim is varied from crown-4 to crown-5 with hydrogen or tert-butyl groups on the para position of the upper rim. Di(tetramethylammonium) salts of the di-ionised ligands are utilised for spectrofluorimetric titration experiments in MeCN. The influence of alkali metal, alkaline earth metal and selected transition and heavy metal (Co2+, Fe2+, Hg2+, Mn2+, Pb2+, Zn2+ and Fe3+) cations on the spectroscopic properties of the two dansyl groups linked to the lower rim of the conformationally locked, di-ionised calix[4]arene-1,2-crown ether frameworks is investigated by emission spectrophotometry. All of the metal cations induce red shifts in the emission spectra of the di-ionised ligands. The metal cations produce enhancement or quenching of the fluorescence emissions. Changes in the fluorescence emission as a function of the metal cation identity, the lower rim crown ether ring size and the absence or presence of upper rim tert-butyl groups are investigated.  相似文献   

11.
硫杂冠醚的合成   总被引:4,自引:0,他引:4  
冠醚化合物对金属离子的络合不仅具有较高的稳定性,而且更重要的是具有良好的选择性。当冠醚环中的氧原子部分或全部被氮或硫原子取代后,它们对碱金属、碱土金属的亲和性能降低,而对过渡金属离子的亲和能力相应提高。硫杂冠醚对亲硫的贵金属、重金属离子具有更强的络合能力和更高的选择性。1974  相似文献   

12.
A series of double-armed benzo-15-crown-5 lariats (3–8) have been synthesized by the reaction of 4′, 5′-bis(bromomethyl)-benzo-15-crown-5 (2) with 4-hydroxybenzaldehyde, phenol, 4-chlorophenol, 4-methoxyphenol, 2-hydroxybenzaldehyde, and 4-acetamidophenol in 43 ~ 82% yields, respectively. The complex stability constants (K S) and thermodynamic parameters for the stoichiometric 1:1 and/or 1:2 complexes of benzo-15-crown-5 1 and double-armed crown ethers 3–8 with alkali cations (Na+, K+, Rb+) have been determined in methanol–water (V/V=8:2) at 25 °C by means of microcalorimetric titrations. As compared with the parent benzo-15-crown-5 1, double-armed crown ethers 3–8 show unremarkable changes in the complex stability constants upon complexation with Na+, but present significantly enhanced binding ability toward cations larger than the crown cavity by the secondly sandwich complexation. Thermodynamically, the sandwich complexations of crown ethers 3-8 with cations are mostly enthalpy-driven processes accompanied with a moderate entropy loss. The binding ability and selectivity of cations by the double-armed crown ethers are discussed from the viewpoints of the electron density, additional binding site, softness, spatial arrangement, and especially the cooperative binding of two crown ether molecules toward one metal ion.Graphical Abstract Synthesis of Double-Armed Benzo-15-crown-5 and Their Complexation Thermodynamics with Alkali CationsYU LIU*, JIAN-RONG HAN, ZHONG-YU DUAN and HENG-YI ZHANG This revised version was published online in July 2005 with a corrected issue number.  相似文献   

13.
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   

14.
Complexes of trifluoromethanesulfonates (triflates) with alkali metals Na, Rb, Cs have been prepared in the presence of various macrocyclic polyether crowns [(12‐crown‐4), (15‐crown‐5) and (18‐crown‐6)]. Depending on the combination of alkali ion with crown, the complexes include separated ion pairs [Na(12‐crown‐4)2] [SO3CF3] ( 1 ) and contact ion pairs [Na(15‐crown‐5)] [SO3CF3] ( 2 ), [Rb(18‐crown‐6)] [SO3CF3] ( 3 ), and [Cs(18‐crown‐6)] [SO3CF3] ( 4 ), in which the triflate acts as a bidentate ligand. It is shown that the choice of crown ether is of paramount importance in determining the solid‐state structural outcome. The complex resulting from the pairing of crown ether ( 1 ) develops, when the crown ether is too small in relation to the alkali ion radius. When the cavity size of the crown ether is matched with the alkali ion radius, simple monomeric structures are identified in 2 , 3 and 4 . The title compounds crystallize in the monoclinic crystal system: 1 : space group P2/c with a = 9.942(3), b = 11.014(2), c = 10.801(3) Å, β = 97.30(2)°, V = 1173.1(4) Å3, Z = 2, R1 = 0.0812, wR2 = 0.1133: 2 : space group P21/m with a = 7.949(2), b = 12.063(3), c = 9.094(2) Å, β = 105.98(2)°, V = 838.3(4) Å3, Z = 2, R1 = 0.0869, wR2 = 0.1035: 3 : space group P21/c with a = 12.847(5), b = 8.448(2), c = 22.272(6) Å, β = 122.90(3)°, V = 2029.5(1) Å3, Z = 4, R1 = 0.0684, wR2 = 0.1044: 4 : space group P21/n with a = 12.871(3), b = 8.359(1), c = 19.019(4) Å, β = 92.61(2)°, V = 2044.2(6) Å3, Z = 4, R1 = 0.0621, wR2 = 0.0979.  相似文献   

15.
具有纳米尺寸的四聚四硫富瓦烯大环冠醚的合成   总被引:2,自引:0,他引:2  
以二(碘乙基)醚和2,3-二氰乙硫基四硫富瓦烯衍生物作为起始原料, 采用腈乙基保护与脱保护技术, 通过多步反应以较好的收率合成了两个纳米结构的大环四硫富瓦烯冠醚5a~5b. 通过循环伏安法(CV)研究了化合物4b5b的电化学性质, 并用1H NMR谱研究了5b与[60]富勒烯之间的相互作用. 结果表明: 5b存在环结构效应, 与[60]富勒烯有一定程度的电荷转移相互作用.  相似文献   

16.
《Analytical letters》2012,45(13):1115-1122
Abstract

The extraction study of alkali metal ions was made with a new type of crown ether, 4′-picrylaminobenzo-15-crown-5 (HL). Upon dissociation in alkaline medium orange-colored HL gives blood-red anion, L?, and extracts selectively K+ (and to a lesser extent Rb+) ion into chloroform as a colored complex of composition ML·HL. A colorimetric determination of 10 - 400 ppm K+ in the presence of < 2000 ppm Na+ was possible using this new crown ether reagent.  相似文献   

17.
Alkali metal cation extraction behaviour for two series of 1,3-alternate, mono-ionisable calix[4]arene-benzocrown-6 compounds is examined. In Series 1, the proton-ionisable group (PIG) is a substituent on the benzo group of the polyether ring that directs it away from the crown ether cavity. In Series 2, the PIG is attached to one para position in the calixarene framework, thereby positioning it over the crown ether ring. Competitive solvent extraction of alkali metal cations from aqueous solutions into chloroform shows high Cs+ efficiency and selectivity. Single-species extraction pH profiles of Cs+ for Series 1 and 2 ligands with the same PIG are very similar. Thus, association of Cs+ with the calixcrown ring is more important than the position of the PIG relative to the crown ether cavity. Solid-state structures of two unionised ligands from Series 2 are presented. Also described is a crystal containing two different ionised ligand–Cs+ complexes.  相似文献   

18.
[AuII([12]anS4)]2+ – X‐ and Q‐Band EPR Evidence of a New Monomeric Gold(II) Compound The reaction of [AuIIICl4] with the thiacrown ether [12]aneS4 leads to an instable [AuII([12]anS4)]2+ complex (5d9, S = 1/2) which was characterized by X‐ and Q‐ band EPR. The spin Hamiltonian parameters g , A Au and P Au were derived using a program package allowing an exact diagonalisation of the spin‐Hamiltonian‐Matrix. The EPR parameters suggest the coordination of only one thiacrown ether ligand in the new AuII complex.  相似文献   

19.
王成云  汪大翚  冷桃花  俞庆森 《有机化学》2005,25(11):1473-1476
(S)-苯丙氨醇和原氯乙酸三乙酯作用得到的手性酰胺醇和手性噁唑啉分别与1,7-二氮-12-冠-4反应, 得到了两种手性N,N′-双支套索冠醚N,N′-二[(S)-N-(1-羟甲基-2-苯基乙基)乙酰胺-2]-1,7-二氮-12-冠-4 (1a)和N,N′-二[(S)-4-苄基-噁唑啉-2-亚甲基]-1,7-二氮-12-冠-4 (1b). 前者应用于D/L-肉碱的手性分离; 后者的铜配合物用于重氮醋酸酯对烯烃的不对称环丙烷化反应.  相似文献   

20.
The condensation of 3,4-bis(2-haloethoxy)benzaldehydes with acyclic α,ω-alkanedithiols in the presence of alkali metal carbonates in dry ethanol, DMF, MeCN and their mixtures with water gives formyl derivatives of benzothiacrown compounds in high yields. The best results are attained when the radius of the hydrated metal cation fits to the crown ether cavity. In the case of Cs+, high yields were observed for crown ethers of any size and composition; this can be explained by a specific template effect of this cation. The influence of the nature of the leaving group in 3,4-bis(2-haloethoxy)benzaldehydes was established for reactions with dithiols containing no ether oxygen atoms. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya No. 11, pp. 1881–1886, November, 2000.  相似文献   

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