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N-十一碳烯和N-烯丙基苯并氮杂15-冠-5和甲基二氯硅烷硅氢加成后, 再与端羟基聚二甲基硅氧烷反应, 用三甲基氯硅烷封端, 合成了两种含苯并氮杂15-冠-5侧基的线型聚硅氧烷。分别以两种聚合物为液膜离子传输载体, 研究了载体种类、阴离子、阳离子种类及载体浓度和盐浓度对离子传输速率的影响, 并考察了膜的稳定性。  相似文献   

3.
冠醚改性聚甲基硅氧烷液膜离子传输性能   总被引:2,自引:0,他引:2  
合成了两种新型的冠醚改性聚甲基硅氧烷,研究了它们作为液膜离子传输载体对离子的传输性能,并考察了膜的稳定性。  相似文献   

4.
朱果逸  蔡振时 《分析化学》1993,21(8):892-895
Li~-和H~-因较强的亲水性,较难穿越液/液界面进行传输。本文报道了冠醚双环已基18冠6对Li~+,Na~+,Rb~-和H~-在水/硝基苯界面的促进传输行为,求得了相应促进传输过程的一系列参数,并对被传输离子在传输过程中的形态变化进行了初步的探讨。  相似文献   

5.
几种单基取代二苯并-18-冠-6的合成   总被引:1,自引:0,他引:1  
刘炳生 《有机化学》1990,10(3):255-257
在功能基取代二苯并-18-冠-6类化合物中,两个苯环上对称地引入两个功能基的合成报道较多,而不对称性引入单个功能基取代的  相似文献   

6.
我们提出了一条合成含有苯并-15-冠-5取代基的某些有机硅冠醚化合物的简易路线。通过Wittig反应合成的4'-乙烯基苯并-15-冠-5,经过双键上的硅氢加成反应,得到几种新型含有冠醚基团的有机硅烷或氯硅烷。后者可以进一步烷氧基化或者水解成冠醚取代的聚有机硅氧烷。此外,还测定了它们对碱金属离子的络合容量和作为相转移催化剂的能力。  相似文献   

7.
吴采樱  朱天清  蔡凌霜  周喜春 《色谱》1994,12(5):320-323
分离测得了不同结构芳香族化合物在单苯并(PSO-B-3-15C5或18C6)、双苯并(PSO-DB-3-15C5)和双苯并双叔丁基(PSO-DTB-3-15C5)取代的15C5聚硅氧烷固定液上的保留指数、相对保留值以及10组异构体的热力学参数──溶解焓△Hs,溶解摘△Ss和自由能△G;研究探讨了冠醚环上不同苯基取代的固定液结构对芳香族位置异构体保留行为的影响;通过热力学参数对不同冠醚柱子选择性的表征,证明了苯并系列冠醚固定液对芳烃位置异构体的良好选择分离,主要取决于冠醚环腔的高电子云密度所产生的定向力和强诱导力以及分子和冠醚环腔的适应程度,特别是空间位阻效应起了重要作用。  相似文献   

8.
合成了一种新型硫杂15-冠-5聚硅氧烷固定液,用其涂制的石英弹性毛细柱呈中等级性。对这类固定液的色谱和热力学性能、分离机理及其应用进行了研究和讨论。  相似文献   

9.
培养了苦味酸锂与二苯并18-冠-6缔合物的单晶体[Li(pic)(H_2O)]_2·[C_(20)H_(24)O_6],化学式为C_(32)H_(32)Li_2N_6O_(22),用X射线法测定了缔合物的晶体结构,证明该晶体属单斜晶系,空间群为P2_1/m,晶胞参数:a=8.299(2),b=25.216(3),c=9.158(2)(?),β=100.34(2)°,V=1885.4(?)~3,Z=2。  相似文献   

10.
以4-[(4-正烷氧基联苯基)-4-碳酰氧基]苯甲酸、二氨基二苯并-18-冠-6和二氨基二苯并-14-冠-4为中间体, 通过溶液缩合反应, 合成了两个系列酰胺型液晶冠醚. 并用元素分析、核磁共振、红外光谱、基质辅助激光解析电离飞行时间质谱、示差扫描量热法和偏光显微镜对其进行了表征. 随分子末端烷氧基碳原子数增加, 化合物4I, 4II, 6I6II的熔点(Tm)和液晶态的清亮点(Ti)逐渐降低, 近晶相范围递增.  相似文献   

11.
本文合成了两种单臂脂环18-冠-6-液晶, 羟甲基 18-冠-6分别和4-(4'-正丁氧基苯甲酰氧基)苯甲酰氯或氯甲酸胆甾醇酯反应得到两种目标物,用DSC和偏光显微镜测定其相变温度,前者相变温度是T~K~N4.0℃和T~N~I33.5℃, 后者相变温度T~K~S-22.4℃, T~S~N6.8℃, T~N~I40.4℃, 用等克分子的硬脂酸和该冠醚液晶制成LB膜, 观察到Y型LB膜的特征.  相似文献   

12.
Introduction  Transportofcationsacrossanorganicliquidmem branewhichseparatestwowaterphaseshasbeenexten sivelyinvestigated .1Thesyntheticmacrocyclicligands ,suchascrownethers ,areusuallyusedasmodelcarrierstomimicthenaturallyoccurringantibioticmacrocycleswhichhavebeenshowntoalterthepermeabilityofbiologicalmembranestocertaincations .2 ,3 Thus ,theyhaveimpor tantapplicationsinbothchemistryandbiologytoselectivecomplexationofvariousmetalcations .4 ,5Itwasreportedthatthedivalenttransition metalcomp…  相似文献   

13.
The effects of transport conditions and the structure of monoazacrownethers on their transport ability for alkali metal cations through a bulkliquid membrane are summarized and discussed based on transport dataobtained in our laboratories. To improve the transport ability,monoazacryptands have been prepared. A lipophilic derivative consisting oftwo 18-crown-6 rings and one 20-crown-6 ring can selectively transport K+from a mixture of Na+, K+, Mg2+, and Ca2+ under pH control.  相似文献   

14.
合成了一种18-冠-6修饰的苝酰亚胺衍生物(1), 研究了其作为主体对金属离子与阴离子的选择性识别行为. 结果表明, 主体1对Ba2+离子具有一定的选择性响应, 并可以通过Ba2+调控主体1的堆积行为; 主体1还对F-离子有选择性响应, F-与苝酰亚胺单元之间发生了阴离子-π相互作用.  相似文献   

15.
A chloroform membrane system containing a given mixture of dibenzyldiaza‐18‐crown‐6 and palmetic acid was applied for transport of Pb2+ ions. The transport was capable of moving metal ions “uphill”. Thus, it was possible to follow the transfer of Pb(II) from the aqueous source phase to the organic layer and from the organic layer to the receiving phase. The effects of thiosulfate concentration in the receiving phase, palmetic acid and dibenzyldiaza‐18‐crown‐6 concentration in the organic phase on the efficiency of the transport system were examined. By using S2O32? ion as metal ion acceptor in the receiving phase, the amount of lead ion transport across the liquid membrane after 150 minutes is 96 ± 1.5%. The selectivity and efficiency of lead transport from aqueous solution containing Cu2+, Tl+, Ag+, Co2+, Ni2+, Mg2+, Zn2+, Hg2+, Cd2+, Ca2+ were investigated. In the presence of thiosulfate as a suitable masking agent in the source phase, the interfering effects of Ag+ and Cu2+ were diminished drastically.  相似文献   

16.
Complexes of cis-syn-cis- and cis-anti-cis-dicyclohexano-18-crown-6(DC18C6) with ammonium, methylammonium, propylammonium, isopropylammonium,butylammonium, isobutylammonium, and tert-butylammonium were generated andstudied in the gas phase using Fourier transform ion cyclotron resonancemass spectrometry to measure exchange equilibrium constants of the guestswith unsubstituted 18-crown-6 (18C6). Semiempirical calculations at the PM3level were also performed for all the complexes. Both the experiments andthe calculations indicate that sterically unhindered ammonium cations bindDC18C6 in preference to 18C6, but that preference decreases or vanishes forammonium cations branched at the carbon. The cis-syn-cis isomer hashigher ammonium affinities than the cis-anti-cis isomer. The experiments andthe calculations both suggest that in the cis-syn-cis isomer the ammoniumcations preferentially bind on the face of the macroring enclosed by thecyclohexano units, but again this preference decreases for stericallycrowded ammonium substituents. These trends are explained in terms of theability of the substituents in the host to stabilize the charge of the guest.  相似文献   

17.
PolysiloxanewithPendantBenzoCrownEtherviaaSpacerofUndecyloxymethylasStationaryPhaseforCapillaryChromatographyLUXue-ran;ZHANGL...  相似文献   

18.
The synthesis and characterization of novel Schiff base liquid crystalline crown ethers prepared from the intermediates 4-(4‘-alkoxylbiphenyl-4-carbonyl)benzaldehyde, cis- and trans-4,4‘-diaminodibenzo-18-crown-6 are described. The structure of these compounds have been well characterized by elemental analysis, IR, ^1H NMR and MS spectroscopy. The liquid-crystalline behavior of these compounds was also inverstigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) with a heating stage and polarimetric analysis.  相似文献   

19.
IntroductionRecentyears ,coordinationpolymershavebeenre ceivedmuchattentionbecauseoftheirinterestingphysi calpropertiessuchaselectricalconductivity ,mag netism ,nonlinearopticalpropertiesandpotentialappli cationsinseparationandcatalyst.1Themodularap proach…  相似文献   

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