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对叔丁基杯[6]-1,4-2,5-双冠醚的合成、构象及其对阳离子的识别性能研究 总被引:1,自引:0,他引:1
采用分步法高产率地合成了系列新型对叔丁基杯[6]双冠醚,并得到了除杯式与1,2,3-交替式构象之外的第3种稳定构象的杯[6]衍生物:1,4-交替式杯[6]-1,4-2,5-双冠醚。研究了它们对碱金属及脂肪胺离子的两相萃取性能,发现杯[6]双冠醚具有与杯[6]单冠醚不同的识别能力。 相似文献
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报道了一种间接缩合法高产率简便合成新型四桥联双杯[4]管道和1,2-3,4-双桥联杯[4]芳烃.杯[4]二酰肼衍生物2与丁二酸酐发生开环反应,以95%的产率得到杯[4]羧酸衍生物4.化合物4在DCC/DMAP/CH2Cl2体系中发生分子间自缩合反应,以90%产率得到新型四桥联双杯[4]管道6.改用高度稀释的条件则以26%的产率得到新型1,2-3,4-双桥联杯[4]芳烃5.新化合物的结构与构象经元素分析、红外、质谱、核磁共振谱等表征证实. 相似文献
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3-芳基-6-(6-/8-取代-4-氯喹啉-3-基)1,2,4-三唑-[3,4-b]-1,3,4-噻二唑类化合物的合成 总被引:2,自引:0,他引:2
研究了3-芳基-4-氨基-5-巯基-1,2,4-三唑与6-/8-取代-4-羟基喹啉-3-酸在三氯氧磷催化下的反应,制得16个的3-芳基-6-(6-/8-取代-4-氯喹啉-3-基)1,2-4,-三唑[3,4-b)-1,3,4-噻二唑,新化合物的结构通过元素分析,IR,^1H NMR和MS确定,讨论了其波谱性质。 相似文献
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新显色剂8-[杯(4)芳烃偶氮]氨基喹啉的合成及其与金的显色反应 总被引:13,自引:0,他引:13
合成了一种新的杂环偶氮类显色试剂 8 [杯 ( 4 )芳烃偶氮 ]氨基喹啉(CAQ) 1。研究了该试剂与金的显色反应的适宜条件 ,在碱性介质中 ,在CTMAB存在下 ,试剂与金生成 1∶1稳定络合物 ,建立了测定金的光度法新体系 ,体系至少可稳定 8h ,λmax =640nm ,ε =2 .0 6× 1 0 5L·mol-1·cm-1,金含量在 0~ 2 2μg 2 5mL内符合比尔定律。方法已用于金矿石中微量金的测定。 相似文献
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1-(5-羧基-1,3,4-三氮唑基)-3-[4-(4-硝基苯基偶氮)苯基] -三氮烯与镉的显色反应及其应用 总被引:10,自引:0,他引:10
1 引 言 三氮烯类试剂是一类广泛用于测定镉、汞、银等元素的显色剂。近年来,为了改善该类试剂的分析性能,人们努力合成了许多取代苯类、吡啶类、苯并噻唑类三氮烯显色剂,但此类试剂灵敏度仍不够高,选择性也不够理想,苯并噻唑类三氮烯显色剂虽灵敏度较高,但选择性仍不理想。作者在研究取代苯类、吡啶类三氮烯显色剂的基础上,又设计合成1-(5-羧基-1,3,4-三氮唑基)-3-[4-(-硝基苯基偶氮)苯基]三氮烯(CTZNPAPT),研究结果表明,试剂与镉有高灵敏反应,并有较好的选择性,摩尔吸光系数2.46× 10… 相似文献
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吡唑类化合物的研究(Ⅵ):—吡唑[3,4—e]并—1,2,4—三嗪和吡唑[3,4—e]并—1,2,3,4—四嗪衍生物的合成 总被引:1,自引:0,他引:1
合成了14种1-苯基-3-氨基-5-氧代-4-取代腙吡唑及其关环产物吡唑[3,4-e]并-1,2,4-三嗪和吡唑[3,4-e]并-1,2,3,4-四嗪衍生物,经元素分析,IR^1H NMR和MS确定了其结构,并讨论了一些化合物的IR和1H NMR波谱性质。 相似文献
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Two novel polysiloxanes with pendant hand-basket type calix[6]-1,3-crown-3 and calix[6]-1,4-crown-4 were prepared by hydrosilylation of p-tert-butylcalix[6]-(2′-allyloxymethyl)-1,3-crown-3 (CA[6]C3) and p-tert-butylcalix[6]-[2′-(ω″-undecenyloxymethyl)]-1,4-crown-4 (CA[6]C4) followed by condensation reaction with silanol-terminated polydimethylsiloxane. The monomeric calix[6]crowns and two calix[6]crown-based polysiloxanes were used as carriers in a bulk membrane. All carriers showed the transport rate of the cations decreased in the order Li+ < Na+ < K+. The flux of K+ for the monomeric calix[6]crown was higher than that for polymeric carrier. In comparison with other carriers, the transport rate of calix[6]crown-4-functionalized polysiloxanes (CA[6]C4PS) towards cesium ions were increased greatly. Competitive transport experiments known to be more useful in industrial fields also revealed to give high cesium transfer rate. 相似文献
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首次合成一系列杯[10]冠醚。通过将对叔丁基杯[10]芳烃和乙二醇双对甲苯磺酸酯或多甘醇双对甲苯磺酸酯在K2CO3/甲苯或Cs2CO3/丙酮体系中反应,得到一系列杯[10]冠醚:1,2-杯[10]冠-4、1,3-杯[10]冠-2、1,2-,1,3-杯[10]冠-3、1,4-杯[10]冠-4、和1,6-杯[10]冠-4。 相似文献
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Arisa Jaiyu 《Tetrahedron letters》2007,48(10):1817-1821
A series of stilbene-bridged calix[4]arenes was synthesized through an intramolecular reductive McMurry coupling of bisbenzaldehyde calix[4]arene in high yields. Tetra- and pentaethylene glycol chains were tethered to the phenolic groups of calix[4]arene to form stilbene-bridged calix[4]arene crown-5 and crown-6, respectively. The presence of stilbene bridge over the calix[4]arene rim effectively prevented the connection of the polyether chains in the cone conformation resulting in the exclusive formation of 1,3-alternate stilbene-bridged calix[4]arene crown product. Compared to the cone analogues, the 1,3-alternate calix[4]arene crown ethers showed a greater extraction ability and selectivity toward Cs+. 相似文献
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The calix[4] open-chain crown ether, 5,11,17,23-tetra-tert-butyl-25,27-di(2-allyloxyethoxyl)-26,28-dihydroxycalix[4]arene was synthesized and used for preparation of solid-phase microextraction (SPME) fibers of enhanced extraction efficiency. The new SPME coating made from calix[4] open-chain crown ether and hydroxyl-terminated silicone oil was developed with the aid of vinyltriethoxylsilane as bridge using sol-gel method and cross-linking technology. The efficiency of the novel fiber in the extraction of polar aromatic and aliphatic compounds, such as phenols, alcohols, and volatile fatty acids, was also investigated. Due to the introduction of the polar open-chain crown ether in calix[4]arene molecules, the calix[4] open-chain crown ether fiber showed much better selectivity and sensitivity to these polar compounds in comparison with calix[4]arene fiber. It also had superior extraction efficiency when compared to commercial poly(dimethylsiloxane)-divinylbenzene and polyacrylate fibers. Parts per billion to parts per trillion level detection limits were achieved for most of the analytes through SPME in conjunction with GC and flame ionization detector. The linear ranges were two to four orders of magnitude, and the RSD values were below 7% for all analytes. The novel fiber was applied to determine volatile alcohols and fatty acids in wine samples. The volatile-free wine prepared in this work was used to assure similar chemical environment for analytes in both calibration solutions and in real wine samples, thus compensating for possible matrix interferences. The established internal standard method using 4-methyl-2-pentanol as internal standard showed satisfactory accuracy and precision. 相似文献
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A novel calix[4] open-chain crown ether (p-tert-butylcalix[4]arene-1,3-bis(allyloxyethy) ether)-modified, organic-inorganic hybrid silica-based monolithic column possessing vinyl ligands for CEC is described. The monolithic silica matrix containing a vinyl functionality was synthesized by in situ cocondensation of tetramethoxysilane (TMOS) and vinyltrimethoxysilane (VTMS) via sol-gel process and chemically modified with calix[4] open-chain crown ether by free radical polymerization procedure using alpha, alpha'-azobisisobutyronitrile (AIBN) as an initiator. Morphology of the monolithic column was examined by SEM and the successful incorporation of calix[4] open-chain crown ether to the vinyl-hybrid monolith was characterized by infrared (IR) spectra. Compared with an unmodified vinyl-hybrid monolithic column, slightly stronger EOF at pH >7.5 was observed for this monolithic column due to the ionization of phenolic hydroxyls on the lower rim of calix[4]arene. VTMS/TMOS ratios in the reaction mixture were varied and 1:4 was found to be optimum to obtain homogeneous monolith with good permeability. The performance of the column was evaluated by nucleotides, beta-blockers, neurotransmitters, and PAHs as test solutes and compared with that of unmodified vinyl-hybrid monolithic column. Greatly improved column performance was obtained due to the host-guest interaction and intermolecular hydrogen bonding provided by the calix[4] open-chain crown ether moiety. The column efficiencies for neurotransmitters and nucleotides are up to 120 000 and 110 000 plates/m, respectively. Migration time and theoretical plate number reproducibilities were reasonable with RSDs less than 1.0 and 1.8% each for within column runs and not more than 7.2 and 8.6% each for column-to-column measurements, using four nucleotides as test solutes. 相似文献
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p-tert-Butylcalix[6]-1,4-2,5-biscrown-4 is a typical member of the family of calix[6]crowns. In the literature, the compound was synthesized from calix[6]arene by two steps and the overall yield based on calix[6]arene was 24%.Herein we wish to report a one-pot method to do this work. By this method the yield was up to 48% and the reaction time was greatly reduced. 相似文献
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The bis(calix [4] arene)3 was synthesized in moderate yield by the reaction of p-tert-butylcalix [4] arene (1) with 1,4-bis(chloromethyl) benzene (2). The conformation of all alkylated product 4 was investigated by the variable-temperature ^1H-NMR. 相似文献