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1.
0 IntroductionCalixarenesandtheirderivativeshaveattractedgreatinterestinhost guestchemistry .Theyarenotedfortheirabilitytoformhost guestcomplexesbytrappingorganiccompounds,smallions ,andgasesintheirtoruslikecavitiesaswellastomimicenzymefunctions[1] .Theyca…  相似文献   

2.
采用紫外分光光度法和荧光光谱法研究了杯[8]芳烃磺酸钠与中性红之间的包合作用.当中性红溶液浓度较高时,杯[8]芳烃磺酸钠的加入使中性红溶液的荧光强度增加,实验证明这是由于中性红与杯[8]芳烃磺酸钠形成了包合物,以致溶液中裸露的中性红分子减少的缘故.介绍了利用光谱法测量包合反应的生成常数方法.结果表明,杯[8]芳烃磺酸钠与中性红可形成1∶1(摩尔比)的包合物.  相似文献   

3.
A few derivatives of calixarenes have been synthesized and characterized by IR, ^1H NNtR, thermal and elemental analysis. The transport of potassium or calcium ion through the liquid membrane, in which the derivatives act as carriers, has been studied. The electron-effect of the substituent on the upper rim of calixarene possesses important effect on the net transport of metal ions. The p- tert-butylcalix[4]arene is the best carrier of calcium ion, compared with p-tert-calix[4]arene(n = 4, 6, 8). The ptert-butylcalix[4]arene acid is better than p-tert-butylcalix [4]arene. The calixr43crown is the best carrier of calcium ions of all the carriers. The pH gradient between the source and receiving phase, and the concentration of K^+ , Ca^2+ ions in the source phase affect mainly transport. After the transport, the pH value of the source phase is found to be decreased, once the calix [n ] arene derivatives act as carrier. But it is not the case for the calix[n] crowns. It might be interpreted as the result of their different mechanisms.  相似文献   

4.
王建玲  候学会  王国庆  吕全建 《河南科学》2011,29(11):1305-1308
将双十一碳烯氧基杯[4]芳烃冠醚聚硅氧烷(C[4]C5-PSO)和上缘稀基取代杯[4]芳烃四苄基醚聚硅氧烷(C[4]TBE-PSO)用作毛细管气相色谱固定相,通过测定一些芳香族位置异构体在2种固定相上的热力学参数△H、△S和△G,探讨了杯[4]芳烃衍生物气相色谱固定相对芳香族位置异构体分子识别的特性和保留机理.  相似文献   

5.
采用杯[8]、杯[6]、杯[4]芳烃对壳聚糖颗粒进行包覆改性,并对钕离子吸附性能进行了研究.研究发现,杯芳烃主要靠氢键与壳聚糖作用而包覆于壳聚糖表面,杯[6]和杯[8]芳烃包覆壳聚糖对钕离子的吸附量均远高于壳聚糖,而杯[4]芳烃包覆壳聚糖对钕离子的吸附量则较低,但在钕离子的平衡浓度较低时对钕离子的吸附仍高于壳聚糖.同时还研究了杯芳烃包覆壳聚糖的吸附量和pH值的关系.  相似文献   

6.
New polyimide containing calix [4] arene moieties on the polymer backbone was successfully synthesized in N- methy1 - 2 - pyrrolidone (NMP) by polycondensations of 3, 3', 4, 4'- oxydiphthalic anhydride (ODPA) with the diaminocalix[4]arene monomer using 3,3'- dimethy1- 4, 4'- The polyimide prepared is soluble in common solvents, such as NMP, DMAc, DMF and chloroform. The polyimide films obtained have excellent thermal stability and mechanical property. At the same time, the liquid membrane transport of potassium ions by the new polyimide was investigated, which testified that compared to ODPA-DADPM polyimide, the polyimide containing culix[4] arenes has the transport ability to metal ions in regard to bulky, cone-like calix [-4] arene moieties.  相似文献   

7.
新型杯[4]芳烃衍生物的合成及结构表征   总被引:5,自引:0,他引:5  
为进一步研究杯[4]芳烃衍生物,并为后续衍生化反应制备中间体,用对叔丁基苯酚和甲醛为原料,利用一步法合成了对叔丁基杯[4]芳烃;再以对叔丁基杯[4]芳烃与碘乙醇的反应,得到了对叔丁基25,27-二羟基-26,28-二羟乙氧基杯[4]芳烃,其结构经1H NMR、13C NMR,、IR、MS和元素分析确证.  相似文献   

8.
杯[4]芳烃经醚化、氨解得到了含酰肼基团的中间体3,在PEG-400存在下,肉桂酰氯与3反应获得了含肉桂酰基的杯[4]芳烃衍生物4;4-经基肉桂酸与氯甲酸乙酯形成的混合酐与3反应,得到了相应的化合物5。用^1H NMR,^13C NMR及IR对4,5进行了结构表征,用MS对4进行了结构确证。DPPH·法测定4,5清除有机自由基活性的结果表明,4,5的自由基清除率约为19%,比杯[4]芳烃母体及肉桂酸都有所提高。  相似文献   

9.
杯[4]芳烃与过量氯乙酸乙酯反应,得到杯[4]芳烃四酯基衍生物2.化合物2与水合肼反应得到杯[4]四酰肼衍生物3,化合物3进一步与异硫氰酸苯酯反应得到四取代杯[4]芳烃酰胺基硫脲衍生物4.反应处理简便,总产率为71%.新化合物的结构经红外光谱、核磁共振氢谱和质谱表征.阳离子萃取实验表明,化合物4不仅对软硬金属离子均有较好的萃取性能,而且对Na 和Ag 有一定的选择性配合能力.  相似文献   

10.
A modified PTC method of preparing tetra-O-alkylated calix[4]arenes is described. Using PEG-400 as phase-transfer catalyst and solid sodium hydrate as a base, full alkylation of calix[4]arenes has been proceeded smoothly in toluene at 90°C. The debutylated calix[4]arene can also be fully alkylated by this method. Supported by the National Natural Science Foundation of China Hu Xubo: born in 1965, Ph. D. Graduate student  相似文献   

11.
以杯[4]芳烃和对叔丁基苯胺为原料,经重氮化-偶合反应,合成了对[(对叔丁基苯基)-偶氮基]杯[4]芳烃,通过IR,~1HNMR对其结构进行了表征,并对其性质进行了初步研究.  相似文献   

12.
杯[4]芳烃与1,2-二溴乙烷反应合成1,3-二溴乙氧基杯[4]芳烃衍生物(化合物1),化合物1分别与乙醇胺和S-(+)-4-甲基-2-氨基-1-戊醇反应,较高产率地合成了含氨基醇片段的杯[4]芳烃衍生物(化合物2)和含手性氨基醇片段杯[4]芳烃衍生物(化合物3).新化合物的结构经元素分析、1HNMR和ESI-MS等表征证实,其结构为1,3-二取代模式且为锥式构象.  相似文献   

13.
合成了杯[4] 芳烃、四对叔丁基杯[4] 芳烃、四乙氧基羰基甲氧基四对叔丁基杯[4] 芳烃、四乙酰基甲氧基四对叔丁基杯[4] 芳烃等4 种杯芳烃,研究了这些杯芳烃对铁( Ⅲ) 的萃取化学,讨论了这些体系的萃取机理,并求出了它们的萃取平衡常数  相似文献   

14.
合成了六对叔丁基杯[6]芳烃,八对叔丁基杯[8]芳烃和四甲基羧基氧基四对叔丁基杯[4]芳烃,并以杯芳烃进行萃取金属离子的研究。对杯芳烃萃取金属的三种机理进行了探讨,并测出其萃取平衡常数。  相似文献   

15.
The inclusion properties of two calix[4]arene derivatives 5, 11, 17, 23-tetra-tert-butyl-25, 27-bis (isopropyl carbamoyl-methoxy)-26,28-diundecenyloxy calix[4]arene (C[4]A) and 25, 27-dibutoxy-5, 11, 17,23-tetra-tert-butyl-26,28-diundecenyloxy calix[4]arene (C[4]B) were studied by gas chromatographic method. It was found that C[4]A could form inclusion complexes with benzene, toluene, methanol and ethanol while C[4]B could only form inclusion complex with methanol, which might be due to the different conformations of C[4]A and C[4]B. Molecular modeling showed that CH/π and OH/π interactions played important roles in the forming of inclusion complexes. Biography: YU Xiao-dong (1973-), male, PhD candidate.  相似文献   

16.
通过具有稳定杯式构象的环氧丙基杯[6] 1,4 冠4与壳聚糖发生接枝交联反应,合成了新型杯[6]冠醚接枝壳聚糖衍生物.研究了其对阳离子的吸附性能后发现,与没有稳定构象的杯[6]芳烃接枝壳聚糖衍生物相比,具有稳定杯式构象的杯[6]芳烃壳聚糖对离子的选择性吸附性能大为提高,尤其是对Na 和Ag 表现出较好的选择性吸附能力.  相似文献   

17.
对-甲基杯[4]芳烃激光光解的研究   总被引:2,自引:0,他引:2  
研究了对-甲基杯[4]芳烃在环己烷和乙腈中的激光光解行为,在环己烷中观察到4200nm及540nm附近的杯芳烃激发三线态吸收峰,极性溶剂乙腈对该三核态有稳定作用,吸收峰显著红移,其三线态双峰特征与不带取取代基的杯[4]芳烃相近,同时发现在330nm附近杯芳烃自由基吸收峰,其动力学分析表明,该自由基按二级动力学衰减。  相似文献   

18.
通过向杯[4]芳烃下沿引入不同基团,合成得到四种杯[4]芳烃衍生物(2,3,4和5),并采用NMR、ESI-MS和EA对所合成的化合物进行结构表征.同时培养得到化合物2,3和4的单晶,解析出晶体结构,发现在化合物3和4的晶体中同时存在杯[4]芳烃的两种主要构象:锥型和部分锥型.通过分析研究,把产生这种现象的原因归结为:当下沿的保护基团具有适度大的尺寸时,就能够阻止苯环的翻转,并且提供足够的空间.当杯芳烃从溶液中析出时,第四个苯环随机地定位,从而使得两种构象并存于同一晶体中.  相似文献   

19.
A new type of calix[4]arenes containing amino acid ester derivatives has been synthesized. Their1H NMR characteristics are discussed. Metal ion extraction experimental has shown that calix[4]arene amino acid esters (2a, 2b) possess good extraction efficiency for transition metal ions (Cu2+, Ni2+, Zn2+) and poor extraction efficiency for alkali metal ions (Na+, K+). Foundation item: Supported by the Ziqang Science Foundation of Wuhan University Biography: MENG Ling-zhi(1947-), female, Associate professor.  相似文献   

20.
An electrochemical method for the simultaneous determination of lead(II) and Cadmium(II) with a calix[6]arene modified carbon paste electrode (CPE) has been developed. Pb2+ and Cd2+ were accumulated at the surface of the modified electrode via formation of chemical complexes with calix[6]arene, and reduced at 1.40 V. During the following anodic potential sweep, reduced lead and cadmium were oxidized, and two well-defined striping peaks appeared at about −0.60 V and −0.84 V. Compared with a bare carbon paste electrode, the calix[6]arene modified CPE greatly improves the sensitivity of determining lead and cadmium. The stripping peak currents change linearly with the concentration of Pb2+ 3.0×10−8–8.0×10−6 mol·L−1 and with that of Cd2+ 6.0×10−8–1.0×10−5 mol ·L−1. The detection limits of Pb2+ and Cd2+ are found to be 8.0×10−9 mol·L−1 and 2.0×10−8 mol·L−1, respectively. The modified carbon paste electrode was applied to determine trace levels of lead and cadmium in water samples. Comparing with that of atomic absorption spectrometry, the results suggests that the calix[6]arene modified CPE has great potential for the practical sample analysis. Foundation item: Supported by the National Natural Science Foundation of China (60171023) Biography: JI Xiao-bo (1980-), male, Master, research direction: electroanalytical chemistry.  相似文献   

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