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1.
C_(60)键合硅胶液相色谱固定相的合成及其性能评价   总被引:2,自引:0,他引:2  
以γ-(乙二胺基)丙基三乙氧基硅烷为偶联剂合成了C60键合硅胶固定相;用元素分析法测定得到该固定相的C60键合量为57.57μmol/g。考察了多环芳烃和杯芳烃在C60键合硅胶固定相上的分离,多环芳烃在该固定相上的洗脱顺序与ODS固定相相似;杯芳烃的洗脱顺序为杯[8]、杯[4]和杯[6]芳烃。  相似文献   

2.
C_(60)键合硅胶液相色谱固定相的合成及其性能评价   总被引:3,自引:1,他引:3  
刘英  达世禄  陈远荫 《色谱》1998,16(2):115-117
 以γ-(乙二胺基)丙基三乙氧基硅烷为偶联剂合成了C60键合硅胶固定相;用元素分析法测定得到该固定相的C60键合量为57.57μmol/g。考察了多环芳烃和杯芳烃在C60键合硅胶固定相上的分离,多环芳烃在该固定相上的洗脱顺序与ODS固定相相似;杯芳烃的洗脱顺序为杯[8]、杯[4]和杯[6]芳烃。  相似文献   

3.
杯芳烃构象的分子力学研究   总被引:2,自引:0,他引:2  
杯芳烃是对位取代的苯酚与甲醛反应得到的环状缩合物,由于其独特的结构和易于衍生化的特点而受到广泛的关注[1].杯芳烃中苯酚单元由亚甲基相连,由于酚羟基端可经杯中央翻转而产生多种构象异构体.杯[4]芳烃有4种典型构象:杯式、部分杯式、1,2-交替式和1,...  相似文献   

4.
含杯[4]芳烃毛细管固定相的制备与色谱性能   总被引:6,自引:2,他引:4  
杯芳烃是由对位取代的苯酚在邻位通过亚甲基连接起来的环状化合物,由于具有可调节大小的空腔,不仅能络合无机离子,而且还可络合有机分子,在分析分离方面有极好的应用前景[1,2].杯芳烃已用于气相色谱[3,4]、离子选择性萃取[5,6]、液相色谱[7,8]和...  相似文献   

5.
研究了杯[6]芳烃-双金属卟啉仿P450酶模型化合物对环己烯环氧化反应的催化性能.考察了温度、氧源浓度、催化剂浓度、底物浓度、卟啉环中位苯基上取代基、溶剂等因素对反应的影响.结果表明,杯[6]芳烃-双金属卟啉的催化性能优于相应的简单金属卟啉单体,且反应遵从Michaelis-Menten规律.这是由于作为疏水结合部位的杯[6]芳烃大环的引入,导致多部位识别协同催化,从而极大地提高了金属卟啉的催化性能.  相似文献   

6.
逐步法合成杯[4]芳烃关环反应的改进   总被引:2,自引:0,他引:2  
对位带有3种或4种不同取代基的杯「4]芳烃一般通过逐步合成法合成.50年代后期,wS和Hllfl比rI'·'a就用[1十1十1十工]的逐步法9步合成出了杯[4]芳烃,总产率相当低·1979年B6hmer等['·'报道用对位取代酚的线型三聚体与2,6一双溪甲基对取代酚在乙酸中进行关环反应合成杯[4」芳烃,这种[3+l」的逐步法只需3步连续反应就能合成带有3种不同取代基的杯卜」芳烃,但最后。步关环产率仍然很低(2%、15%)[".后来*dhmeTD'等将关环反应改进为在TICI。/二氧六环体系中进行,产率有所提高,这种逐步法曾用于不对称杯[4」芳烃的…  相似文献   

7.
合成了两种新型杯芳烃衍生物苄基杯[4]芳烃聚硅氧烷(C[4]TECM-PSO)和酯基杯[4]芳烃聚硅氧烷,并用作毛细管气相色谱固定液。通过测定6组芳香族化合物在两种固定液上的热力学参数ΔH、ΔS、ΔG、ΔS/ΔH、Δ(ΔH)、Δ(ΔS),探讨了它们对于所测化合物的分子识别和色谱分离机理。结果显示,酯基杯[4]芳烃上测得的ΔH、ΔS远高于苄基杯芳烃上所测得的热力学参数,表明其与溶质的作用力强,构型效应更明显。同时对两种杯[4]芳烃的包结作用进行了探讨。  相似文献   

8.
杯芳烃的液膜传输作用是其典型的超分子化学特征之一[1].在探索杯芳烃及其衍生物作为流动载体传输金属离子的能力及传输作用的规律性,以及模仿细胞壁两边金属离子的传递过程及其控制方式方面有潜在应用前景.Izat[2]等认为,只有当源相处于强碱性条件(pH>...  相似文献   

9.
对-叔丁基杯[4]芳烃在环己烷中的激光光解研究*袁立华1姚思德2庄志豪1林念芸2(1.四川联合大学化学系成都610064)(2.中国科学院上海原子核研究所辐射化学实验室上海201800)关键词对-叔丁基杯[4]芳烃激光光解三线态中图分类号O621.2...  相似文献   

10.
杯芳烃固定液分子识别的热力学性质   总被引:3,自引:0,他引:3  
用毛细管气相色谱法测得了5组芳香族位置异构体在杯芳冠醚聚硅氧烷(C[4]C5_PSO),二乙氧基杯芳烃聚硅氧烷(C[4]E_PSO)和二丁氧基杯芳烃聚硅氧烷(M_C[4]B_PSO)3种杯芳烃固定液上的热力学参数ΔH、ΔS、ΔG,然后用热力学及超热力学的方法探讨了杯芳烃对异构体的分子识别特性和保留机理。  相似文献   

11.
A siloxane-functionalized calix[4]pyrrole derivative was synthesized starting from the corresponding alcohol-functionalized calix[4]pyrrole. Structural elucidation was carried out by using NMR spectroscopy, mass spectrometry and X-ray diffraction analysis. The use of this siloxane-functionalized calix[4]pyrrole for modification of various silica solid supports (silica gel 60, fume silica, and SiO2 nanopowder) was studied. Characterization of the modified silica solid supports was achieved by FTIR, TGA, and elemental analysis. It was also shown that the production of silica nanoparticles is possible via a sol-gel reaction of siloxane-functionalized calix[4]pyrrole and tetraethoxysilane (TEOS). Calix[4]pyrrole modified silica solid supports were found to sense chloride anions of Azure A dye.  相似文献   

12.
Calix[4]arene-capped [3-(2-O-beta-cyclodextrin)-2-hydroxypropoxy]propylsilyl-appended silica particles (C4CD-HPS), a new type of substituted beta-cyclodextrin-bonded chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC), have been synthesized by treatment of bromoacetate-substituted [3-(2-O-beta-cyclodextrin)-2-hydroxypropoxy]propylsilyl-appended silica particles (BACD-HPS) with calix[4]arene oxyanions in anhydrous N-methyl-2-pyrrolidone. The synthetic stationary phase is characterized by means of elemental analysis. This new type of CSP has a chiral selector with two recognition sites: calix[4]arene and beta-cyclodextrin (beta-CD). The chromatographic behavior of C4CD-HPS was studied with several disubstituted benzenes and some chiral drug compounds under reversed-phase conditions. The results show that C4CD-HPS has excellent selectivity for the separation of aromatic positional isomers and enantiomers of chiral compounds due to the cooperative functioning of calix[4]arenes and beta-CDs.  相似文献   

13.

In this study, we tried to reduce polarization of silica surface by chemically bonding cholorosulfonyl calix[4]arene (CSC[4]A) and silica (Si–O–Cl) to improve dispersion between filler and elastomer. To confirm synthesis of CSC[4]A, 1H NMR, 13C NMR, and IR spectrophotometry were used. Obtained composite of chemically bonded silica and CSC[4]A was characterized by TGA. Compounds (contained silica, silica and silane, silica-calix system) were prepared to investigate the effect of silica-calix system (CSC[4]A-SiO2) on the rheological and mechanical properties of rubber compounds based on natural rubber/cis-butadiene rubber (NR/BR) blend in tire tread formulation. The rheological and mechanical properties of three samples were investigated by different devices and a surface morphology was evaluated by FESEM technique. The results revealed that the curing behavior of the compound with CSC[4]A-SiO2 did not significantly differ from other compounds, while reversion was considerably reduced compared with that to other compounds. Also, the mechanical properties of compound with CSC[4]A-SiO2 were improved dramatically especially in fatigue resistance.

  相似文献   

14.
通过对杯[4]芳烃以及杯[6]芳烃上缘进行烯丙基化和硅氢加成2步衍生化反应得到硅氢化杯[4]芳烃以及硅氢化杯[6]芳烃,再将这2种硅氢化杯芳烃衍生物分别接枝到超细SiO2上。在不同的pH值条件下,就2种杯芳烃接枝超细SiO2衍生物对水合Cu2+及Ag+的萃取性能进行了研究。结果表明,与对叔丁基杯芳烃相比较,杯芳烃接枝超细SiO2衍生物对Cu2+和Ag+的萃取率都有所提高,其中杯[4]芳烃接枝超细SiO2对Ag+的最高萃取率达到98.78%,杯[6]芳烃接枝超细SiO2对Cu2+的最高萃取率达到67.74%。  相似文献   

15.
曾昭睿  王建玲 《分析化学》1998,26(9):1060-1064
合成了两种新型的杯(4)芳烃衍生物:5-1′,1′-二甲基十一烯氧基苯基甲基-11,17,23-三-1,1-二甲基乙基-25,26,27,28-四苄氧基杯(4)芳烃C(4)TB)及5-1′,1′-二甲基十一烯氧基苯基甲基-11,17,23-三-1′,1′-二甲基-25,26,27,28-四乙氧羰甲氧基(C(4)TECM)其结构经元素分析IR,^1HNMR,MS的数据证实,分别将其与OV-1701固  相似文献   

16.
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   

17.
Reactions of UCl4 with calix[n]arenes (n = 4, 6) in THF gave the mononuclear [UCl2(calix[4]arene - 2H)(THF)2].2THF (.2THF) and the bis-dinuclear [U2Cl2(calix[6]arene - 6H)(THF)3]2.6THF (.6THF) complexes, respectively, while the mono-, di- and trinuclear compounds [Hpy]2[UCl3(calix[4]arene - 3H)].py (.py), [Hpy](4)[U2Cl6(calix[6]arene - 6H)].3py (.3py), [Hpy]3[U2Cl5(calix[6]arene - 6H)(py)].py (.py) and [Hpy]6[U3Cl11(calix[8]arene - 7H)].3py (.3py) were obtained by treatment of UCl4 with calix[n]arenes (n = 4, 6, 8) in pyridine. The sodium salt of calix[8]arene reacted with UCl4 to give the pentanuclear complex [U{U2Cl3(calix[8]arene - 7H)(py)5}2].8py (.8py). Reaction of U(acac)4 (acac = MeCOCHCOMe) with calix[4]arene in pyridine afforded the mononuclear complex [U(acac)2(calix[4]arene - 2H)].4py (.4py) and its treatment with the sodium salt of calix[8]arene led to the formation of the 1D polymer [U2(acac)6(calix[8]arene - 6H)(py)4Na4]n. The sandwich complex [Hpy]2[U(calix[4]arene - 3H)2][OTf].4py (.4py) was obtained by treatment of U(OTf)4 (OTf = OSO2CF3) with calix[4]arene in pyridine. All the complexes have been characterized by X-ray diffraction analysis.  相似文献   

18.
Octadecylsilanized silica (ODS) was coated with meso-octarnethylcalix[4]pyrrole to obtain a novel calix[4]pyrrole containing stationary phase for HPLC. Compared to ODS, the new stationary phase showed a relatively large retention and an improved separation for phenolic compounds and organic anions, using pure water as mobile phase. The results can be ascribed to the interaction between analytes and calix[4]pyrrole.  相似文献   

19.
Summary: A new calix[4]arene‐based periodic mesoporous organosilica has been synthesized using tetraethoxysilane (TEOS) and a calix[4]arene‐based silane monomer as the precursors and cetyltrimethylammonium bromide (CTAB) surfactant as the structure‐directing template, and is shown to be capable of visual detection and entrapment of NO2.

Synthesis of the novel mesoporous organosilica material containing covalently bound tetra‐O‐alkylated calix[4]arene hosts.  相似文献   


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