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1.
制备了一种新型的发色团分子,实际是由普通发色团分子与β-环糊精形成的超分子包合物.其中的普通发色团分子被设计为哑铃型,并且哑铃形的一边在形成包合物后再完成,使形成的超分子包合物不发生解包合.包合物中β-环糊精对发色团分子的保护可以完全阻止发色团分子的聚集,减弱了材料中发色团分子间的静电相互作用.这种利用超分子包合物对发色团分子的修饰方法可以提高极化过程的效率,从而增加材料的电光活性。  相似文献   

2.
通过拉曼光谱法研究氯霉素与β-环糊精相互作用形成包合物的过程,探讨拉曼光谱作为一种新的验证包合物形成方法的可行性.采用饱和水溶液法制备氯霉素包合物,共聚焦拉曼光谱仪分别检测氯霉素、β-环糊精、氯霉素与β环糊精的物理混合物、氯霉素包合物的拉曼光谱并对照分析.结果表明,拉曼光谱法可说明氯霉素的苯环结构和易水解基团二氯乙酰胺...  相似文献   

3.
β-环糊精与水杨醛缩间氨基苯酚包合物的微环境效应研究   总被引:1,自引:0,他引:1  
采用微波促进法首次制备了以β-环糊精(CDs)为主体、水杨醛缩间氨基苯酚(SMA)为客体的超分子包合物,通过多种谱学方法对固体包合物进行了表征.研究表明二者形成摩尔比为1∶1的包合物,并且求得包合物的结合常数Ka为4.4×103L/mol.包合物在水溶液中具有更好的溶解性能和稳定性.同时,从微环境的角度比较研究了不同溶剂对SMA包合前后的UV光谱的影响以及不同pH值的变化对SMA和包合物的影响特征.结果表明溶液中微环境的不同对客体及超分子包合物的电子光谱有着显著而不同的影响.  相似文献   

4.
二茂铁及其衍生物不能牢固吸附于电极表面 ,特别是其氧化态 ( Fc+ )溶于水 ,影响了电极的稳定性 [1] .为解决这一问题 ,可采用合成有特殊官能团的二茂铁衍生物 [2 ] ,并利用 Nafion膜的双亲性将二茂铁固定于玻碳电极表面 [3]等方法 .这些方法制备的电极在使用过程中二茂铁仍会从电极表面缓慢流失 .我们利用二茂铁能与 β-环糊精形成 1∶ 1的包合物的性质[4] ,在乙二醇中制成了该包合物并掺杂于石墨粉中 ,用固体石蜡作粘合剂制成了 β-环糊精 -二茂铁包合物修饰碳糊电极 .首次把主客体包合物引入碳糊电极 ,大大改善了电极的性能 .该电极性能…  相似文献   

5.
β-环糊精包合物的结构研究   总被引:29,自引:3,他引:26  
β 环糊精 (简称 β CD)是由 7个葡萄糖残基以α 1 ,4 糖苷键连接而成的环状化合物 ,具有亲水的外围及疏水的内腔 ,在溶液中可与多种有机物形成包合物[1,2 ].因 β CD对客体分子的形状、大小和极性等具有选择性[3],因而可能形成不同物质的量的比的结构模型包合物 .有关包合物制备及物质的量的比确定的文献报道很多[4 ,5 ],但研究包合物结构模型的文献却不多见 .本文用DSC确定了 β CD与胆固醇、癸二酸和香兰素包合物的最佳物质的量的比 ,用XRD分析包合物晶体的结构周期 ,得到较明显的 2倍于 β CD内腔高度的结构周期和“头头…  相似文献   

6.
虫草素与羟丙基-β-环糊精的包合行为及性能研究   总被引:1,自引:0,他引:1  
通过饱和溶液方法制备了虫草素(COR)与羟丙基-β-环糊精(HPβCD)形成的包合物.采用紫外-可见光谱法对水溶液中HPβCD与虫草素(COR)的包合行为进行研究,利用Job曲线法确定COR/HPβCD包合物的包合比,通过1 H NMR和2D NMR、DSC、TG、XRD、FTIR和SEM对COR/HPβCD包合物进行表征和性能测定.结果表明,COR/HPβCD包合物的包合比为1:1,虫草素与HPβCD形成包合物后,其水溶性、热稳定性及生物环境稳定性都得到明显提高.COR/HPβCD包合物在医药领域具有潜在的应用前景.  相似文献   

7.
2-羟基-4-甲氧基二苯甲酮-β-环糊精包合物的制备与表征   总被引:3,自引:0,他引:3  
罗维巍  宫红  姜恒 《化学研究》2006,17(1):35-37
采用研磨法合成了2-羟基-4-甲氧基二苯甲酮-β-环糊精包合物.用差示量热扫描分析、热重分析、红外分析、X射线衍射分析对包合物进行了鉴定.紫外光谱分析表明,包合没有改变2-羟基-4-甲氧基二苯甲酮的性质,包合物仍然具有吸收紫外线的能力.  相似文献   

8.
防冰高分子材料作为一种新型功能高分子材料,在电力、通讯及运输等领域有广泛应用.表面的覆冰现象往往开始于冰的成核,发展于冰的传递,危害于冰的积聚.针对材料表面冰晶形成的环节,揭示冰晶形成的分子机制是设计和开发防冰高分子材料的关键.本文简要介绍了本课题组在防冰高分子材料领域的研究进展,包括设计搭建的基本研究设备,以及具有调控冰成核、控制冰传递、降低冰黏附等不同功能的防冰高分子材料.  相似文献   

9.
何华  汤瑶  孙成  王晓蓉 《化学学报》2006,64(2):175-181
制备了β-环糊精(β-CD)-三氟氯氰菊酯(CHL)包合物,采用差示扫描量热分析法和核磁共振波谱法对包合物进行表征.实验采用1HNMR研究包合物的空间结构,推测出三氟氯氰菊酯同β-CD的包合方式是从大口端进入β-CD.用化学软件对β-CD与CHL包合方式计算发现,CHL从β-CD的大口端和小口端进入,总能量分别为108.1kJ/mol与129.2kJ/mol,表明CHL从β-CD的大口端进入形成的包合物能量最低,结构最稳定.在25℃下,实验测得β-CD-三氟氯氰菊酯包合物形成常数为340.6L?mol-1,包合比是1∶1.热动力学方法研究了温度变化对包合反应的影响,计算得出包合过程的焓变-50.29kJ?mol-1、熵变120.6J?K-1?mol-1及自由能变化-14.45kJ?mol-1,进而确定了包合反应的主要驱动力是焓.  相似文献   

10.
采用荧光光谱研究了抗癌药物喜树碱(CPT)与4-磺酸基杯芳烃[6](SCX6)间的相互作用,结果表明二者形成了1∶1的包合物.通过计算测得包合物的结合常数和二者形成过程的热力学参数,主体分子和离子型客体之间除了通常的疏水作用力还有额外的静电作用力.包合物的形成提高了喜树碱的溶解度并保护了活性内酯环结构.  相似文献   

11.
Pyridine-based, structurally isomeric two macrocyclic compounds displayed a remarkably different complexation nature. The cage-type compound has an ideal structure for spherical cations, especially for the NH4+ ion, but the reaction with some transition metals and Ln3+ produced its protonated species. On the other hand, its isomer formed complexes with alkali metals and lanthanides (1:1) and also with transition metals. Some structures of the complexes were clarified by crystallographic analyses.  相似文献   

12.
Oxidation of hexabenzylhexaazaisowurtzitane   总被引:1,自引:0,他引:1  
Oxidation of hexabenzylhexaazaisowultzitane by different Cr(Ⅵ) reagents has been studied, and a very stable amide product, hexabenzoylhexaazaisowurtzitane, has been obtained.  相似文献   

13.
研究了碱式笼形聚偕胺树脂(BCAO)吸附Pd(Ⅱ)的行为.溶液pH值对吸附容量有重要的影响.在一定条件下,BCAO在中性溶液中吸附Pd(Ⅱ)的量是酸性溶液中的一倍以上,但提高溶液的酸性有利于从稀溶液中回收钯.Pd(Ⅱ)在盐酸溶液中显H_2PdCI_4结构.吸附结果生成AO-Pd络合物.当溶液被碱中和至近中性时,Pd(Ⅱ)以Pd~(2+)和[Pd(OH)_2CI_2]2-的形式存在,吸附过程中先后生成AO-Pd,AO-Pd_2和AO_2-Pd_3先等不同组成的给合物.由于AO与Pd(Ⅲ)之间较大的电位差,部分Pd(Ⅱ)被还原成Pd(0),并汇聚在BCAO表面上.  相似文献   

14.
Designing compounds for the selective molecular recognition of carbohydrates is a challenging task for supramolecular chemists. Macrocyclic compounds that incorporate isophtalamide or bisurea spacers linking two aromatic moieties have proven effective for the selective recognition of all-equatorial carbohydrates. Here, we explore the molecular recognition properties of an octa-urea [Pd2L4]4+ cage complex ( 4 ). It was found that small anions like NO3 and BF4 bind inside 4 and inhibit binding of n-octyl glycosides. When the large non-coordinating anion ‘BArF’ was used, 4 showed excellent selectivity towards n-octyl-α-D-Mannoside with binding in the order of Ka≈16 M−1 versus non-measurable affinities for other glycosides including n-octyl-β-D-Glucoside (in CH3CN/H2O 91 : 9).  相似文献   

15.
合成了3种具有对不同瓜环选择性各异的双探针N-苄基取代笼状客体, 它们分别是N-苄基六次甲基四胺盐酸盐(1), N-苄基喹啉环啶盐酸盐(2), N-苄基-1,4-二氮杂双环[2.2.1]辛烷盐酸盐(3), 利用1H NMR和MS等方法对这些客体进行了表征. 1H NMR显示, 六元瓜环仅对这些客体的苄基探针部分具有选择性作用, 形成作用比为1∶1的不对称包结配合物; 七元瓜环对客体13的苄基探针部分具有选择性作用, 形成作用比为1∶1的不对称包结配合物, 而对客体2的笼状奎宁环啶基部分具有选择性作用, 也形成作用比为1∶1的包结配合物; 八元瓜环也仅对这些客体的苄基探针部分具有选择性作用, 形成作用比为1∶2的对称包结配合物.  相似文献   

16.
A new series of unsaturated pure and boron‐substituted hydrocarbons containing a perfect planar tetracoordinate carbon (ptC) have been proposed by performing density functional computations. The ptC is effectively stabilized through three‐dimensional delocalization of ptC's lone pair into π‐conjugated systems, by utilizing a new strategy opening a brand new way of designing ptC structures. Compared to previously proposed ptC‐containing hydrocarbon cage compound, a neutral hydrocarbon designed here might be a more viable target for synthetic attempts. © 2009 Wiley Periodicals, Inc. J Comput Chem 2009  相似文献   

17.
内嵌富勒烯由于其结构新颖以及独特而优异的性质在国际上引起持续而广泛的关注,成为近年来的研究热点之一.目前已经研究发现的内嵌富勒烯多达近百种,从惰性气体到碱土金属再到稀土元素都已被成功地嵌入到不同尺寸的碳笼中.其中金属离子或含金属的离子簇内嵌入富勒烯碳笼形成的内嵌金属富勒烯,以其种类丰富、结构多样成为内嵌富勒烯的主要研究对象.本文就近年来研究报道的种类繁多的内嵌富勒烯按其内嵌物类型进行归纳阐述,为今后开发更多新型的内嵌富勒烯提供一定的参考.  相似文献   

18.
The traditional method for opening the electron shells of noble gas atoms involves a strong electronegative atom or group. However, this approach is limited to only heavy noble‐gas atoms, such as Kr and Xe. In this paper, we performed accurate calculations of He@C8H8 and He@C10H16 and showed the possibility of opening the electron shell of a light noble‐gas atom. © 2012 Wiley Periodicals, Inc.  相似文献   

19.
Polymers having polyhedral oligomeric silsesquioxane (POSS) in the main chains are an important class of organic–inorganic hybrid materials. Despite the increasing attention to the POSS polymers, variation of the monomers is still limited. Herein, we have proposed side‐opening POSS (SO‐POSS) monomers. Platinum‐catalyzed hydrosilylation polymerization proceeded to produce polysiloxanes having SO‐POSS in the main chains. The obtained polysiloxanes showed good solubility, high thermal stability, high transparency, and tunable reflective index. In addition, cyclic compounds were obtained during the investigation of the polymerization, and were synthesized with high selectivity under the slightly diluted conditions. The obtained cyclic compounds showed high thermal stability due to the silsesquioxane backbone, and the high dispersibility as a filler in poly(methyl methacrylate) was demonstrated. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2243–2250  相似文献   

20.
Porous materials with well‐defined pore structures have received considerable attention in the past decades due to their unique structures and wide applications. Most porous materials such as zeolites, metal‐organic frameworks, covalent organic frameworks, and porous organic polymers are extended to infinite frameworks or networks by robust covalent or coordination bonds. Porous molecular cages composed of discrete molecules with permanent cavities are an emerging class of porous material and the discrete molecules assemble into solids by weak intermolecular interaction. In comparison to porous extended solids such as metal‐organic frameworks and covalent organic frameworks, porous molecular cage solids are generally soluble in organic solvents thus allowing solution processing, making them more convenient to apply in many fields. This review mainly focuses on the recent advances of application of porous molecular cages (porous organic cages and metal‐organic cages) for enantioselective recognition and separation from 2010 to present, including gas chromatography, capillary electrochromatography, chiral fluorescent recognition, chiral potentiometric sensing, and enantioselective adsorption. Furthermore, the two important family members of porous molecular cages, porous organic cages and metal‐organic cages, are also discussed.  相似文献   

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