柱芳烃的合成及主客体化学研究进展

柱芳烃是由对苯二酚或对苯二酚醚通过亚甲基桥在苯环的对位连接而成的一类环状低聚物, 是一类新型的大环主体分子. 本文介绍了柱芳烃和功能化柱芳烃分子的合成, 以及在分子识别、 自组装等主客体化学方面的最新研究进展, 并对其研究前景进行展望.     

柱芳烃化学:从合成、主客体性质到自组装性能的研究进展

柱芳烃是由对苯二酚或对苯二酚醚通过亚甲基桥在苯环的对位连接而成的一类新型环状低聚物,是一类新的大环主体分子.本工作介绍了柱芳烃的合成和功能化衍生,重点总结了其在分子识别、自组装和生物应用等主客体化学方面的最新研究进展.     

基于柱[5]芳烃的超分子组装研究进展

介绍了柱[5]芳烃基于主客体性质和柱状立体结构的超分子组装,以及边缘取代基对柱[5]芳烃的溶解性、功能性和主客体性质的影响。     

基于冠醚和柱芳烃主客体识别的超分子聚合物材料

超分子聚合物材料是高分子科学、超分子化学和材料科学3个学科相结合的产物.通过精妙的设计,我们不仅可以赋予它传统高分子材料所拥有的光学、电学以及力学等性能,同时还可以使其具有超分子材料的动态可逆性和刺激响应性.已用于构筑超分子聚合物材料的主客体识别体系有很多,从识别体系中的主体来说,包括基于冠醚、环糊精、杯芳烃、葫芦脲、柱芳烃等大环的主客体体系.其中,冠醚作为第一代大环主体,它的模板合成直接开辟了超分子化学这一领域,而柱芳烃是最近发展起来的一类新的大环主体,它具有刚性的骨架,并且制备简单,容易功能化,同样也受到超分子化学家们的广泛关注.本文着重综述了我们课题组基于冠醚和柱芳烃主客体识别所构筑的超分子聚合物材料.在这些材料的制备中,我们利用了主客体识别的刺激响应性、可逆性和选择性,来实现对这类材料的组装结构以及功能的精确调控.     

一种基于21-冠-7和柱[5]芳烃分子识别的超分子聚合物

合成了一个苯并21-冠-7-柱[5]芳烃杂二主题主体分子(1),二级铵盐是21-冠-7大环的合适客体,而柱[5]芳烃空腔可以强络合中性客体基元5-(1H-1,2,3-triazol-1-yl)pentanenitrile(TAPN),因此选择含有2个TAPN的客体2和含有2个二级铵盐的客体3作为连接体,依靠二级铵盐?21-冠-7和中性客体?柱[5]芳烃正交主客体作用,构筑了一个三组分超分子聚合物(1,2和3的摩尔比为1∶0.5∶0.5),该组装体的形成得到了1H-NMR、DOSY、黏度和SEM等手段的表征?所构筑的超分子聚集体是浓度依赖的,其形成超分子聚合物的临界浓度为49 mmol/L.     

杯芳烃和柱芳烃桥梁部位的衍生及其功能化

随着大环化学的快速发展,对杯芳烃、柱芳烃及其他类似化合物的桥梁亚甲基部位进行高效修饰的方法日益引起人们的关注.桥梁部位修饰后的大环衍生物,在不改变其原有属性的基础上增加了新的功能,不仅可以引入更多的功能基团,而且可以通过主客体的自组装行为,进一步拓展杯芳烃和柱芳烃等超分子大环在药物递送、化学传感、荧光体系构建等诸多领域...     

柱[6]芳烃的合成及在分子识别中的应用研究进展

柱芳烃是近年来超分子研究领域中备受关注的一类新型大环主体化合物。与柱[5]芳烃相比,柱[6]芳烃因具有更大的管状空腔结构而表现出了独特的主客体性能。介绍了柱[6]芳烃的结构与构象,并重点阐述了柱[6]芳烃的合成方法以及在分子识别中的应用研究进展。     

基于柱芳烃的有机功能材料

超分子化学起源于主客体化学,其发展亦很大程度上依赖于主客体化学。而大环受体分子作为主客体化学重要组成部分在有机功能材料的构筑方面已逐渐显示出其无穷的魅力。在过去的几十年里,科研工作者们深入研究了包括冠醚、环糊精、杯芳烃、葫芦脲、柱芳烃在内的多种有机超分子主体化合物。其中,柱芳烃作为一种新型的易官能化的主体分子,由于其独特的刚性柱状结构和优良的物理、化学性质日益受到广泛关注。它为有机功能材料的制备以及超分子化学的发展提供了更多可能。到目前为止,基于柱芳烃的有机功能材料已在分子识别、细菌病毒抑制、农药检测、重金属离子识别、光传感、纳米粒子的稳定、催化、生物传感及药物控释等多个领域得到运用。本文结合这些材料现阶段的研究进展,对其在上述领域的应用进行简单明晰地总结与展望。     

四氨基柱[5]芳烃二聚体的合成、结构及性质研究

构象固定的刚性多环主体分子为构筑高级复杂的机械互锁结构提供了重要平台. 为挑战合成刚性多环主体并进一步构筑多层次机械互锁结构, 氧杂杯[4]芳烃桥连的柱[5]芳烃二聚体经过Raney Ni催化氢化还原硝基、与叔丁氧羰基(Boc)-β-丙氨酸缩合和脱去N-Boc保护基三步反应, 生成了四氨基柱[5]芳烃二聚体. X射线单晶衍射实验表明三环目标主体分子具有双桶望远镜形状, 并且构象刚性, 随取代基不同仅有微小变化. 此外, 该四氨基二聚体可作为主体与己二腈形成高稳定性的1∶2络合物. 该研究为制备复杂超分子体系提供了新的机会.     

基于柱[5]芳烃主客体包结构筑分子响应型超分子水凝胶

主客体相互作用是在水溶液中与大环主体分子形成稳定的包结物的理想驱动力.以功能化的苯并咪唑衍生物为客体(M),水溶性柱[5]芳烃为主体构建了一种分子响应型超分子水凝胶.通过1H NMR, 2D NOESY和扫描电子显微镜(SEM)研究了水凝胶的成凝胶机理.有趣的是,主客体包结作用、柱[5]芳烃间有序的"外腔"π-π相互作用和分层堆积对于获得超分子水凝胶是必不可少的,非共价键相互作用的动态可逆性使凝胶体系对温度变化/化学刺激产生响应.此外,加入竞争性客体己二腈(ADN)/百草枯(PQ)后,柱[5]芳烃基水凝胶可转化为溶胶.因此,该超分子水凝胶可以选择性识别有机分子.     

Desymmetrized Leaning Pillar[6]arene

In this work, a novel version of macrocyclic arenes, namely leaning pillar[6]arenes, was discovered and it can be considered as a tilted version of a pillar[6]arene with two hydroxy/alkoxy functionalities removed. Through a facile two‐step synthetic approaches, in conjunction with a diversity of post‐modification possibilities, a series of leaning pillar[6]arenes, with good cavity adaptability and enhanced guest‐binding capability, was synthesized, and their self‐assembly in single‐crystal states is presented. DFT calculations demonstrated that the lower rotational barrier of unsubstituted phenylene rings, the uneven electron density centered at the leaning phenyl rings, and the polarization effect along the edge generated by the hydrogen‐bond‐induced orientation of hydroxy groups greatly affected the host‐guest properties, and meanwhile provided an intuitive explanation for the pillar‐like and rigid structure of traditional pillar[6]arenes. Significantly, the crystal structure of cyclo‐oligomeric quinone was obtained by direct oxidation of leaning pillar[6]arenes.     

Synthesis and host-guest properties of pillar[6]arenes

A facile method for the synthesis of pillar[6]arenes was developed.A series of pillar[6]arenes were prepared with FeCl 3 as catalyst and chloroform as solvent at room temperature in moderate yields(30%-40%).Their host-guest properties with n-cetyltrimethyl ammonium bromide were investigated by 1 HNMR.The results showed that high selectivity in the host-guest relationship became apparent between pillar[6]arenes and pillar[5]arenes based on the different size of the inner cavity.     

Synthesis of pillar[7]arene

The first synthesis of pillar[7]arene is reported with two methods.Method A:the FeCl₃-catalyzed condensation reaction of 1,4- dimethoxybenzene（1） with paraformaldehyde in CHCl₃ gave dimethoxypillar[7]arene（3）.Method B:the p-toluenesulfonic acid catalyzed condensation reaction of 2,5-bis（benzyloxymethyl）-1,4-dimethoxybenzene（2） in CH₂Cl₂ gave compound 3.Demethylation of 3 with BBr₃ gave pillar[7]arene（4）.The pillar[7]arene might be a perspective macrocyclic host in host-guest chemistry.     

Effect of varying bases on preferential crystallization of C-methylresorcin[4]arene and calix[6]arene

Preferential crystallization from a mixture of C-methylresorcin[4]arene (RsC1) and calix[6]arene (Calix6) in the presence of different bases has been investigated. In the presence of pyridine, a boat conformer of RsC1 crystallizes, whereas in the presence of triethylamine, Calix6 crystallizes in a symmetrically distorted conformation. The packing arrangements of the macrocycles show discrete solvent pockets for calixarenes and channels for resorcinarenes.     

Hexanoate-Cucurbit[7]uril: Highly Soluble with Controlled Release Ability

Current drug delivery systems gain more functions with increased complexity. With the idea of less is more, we synthesized hexanoate-cucurbit[7]uril (CB[7]C₅COONa) with multiple promising features for drug delivery. The hexanoate group integrates multiple functions. It endows CB[7]C₅COONa extremely high solubility of over 600 mg mL⁻¹ and well-defined pH-controlled release ability without sacrificing on the high binding affinity of CB[7] cavity. Based on the pH-controlled release ability, CB[7]C₅COONa can be used for controlling the bioactivity of drug molecules. We anticipate that the strategy of function integration would be useful for the design of simple yet powerful drug delivery systems.     

Hydrogen-bonded 1D and 2D Assemblies of Tetraiso-butyl-resorcin[4]arene in the Crystalline State

1 INTRODUCTION There is continuing interest in the assembly of molecular capsules based on concomitant formation of multiple hydrogen bonds between smaller mole- cular components[1]. A particularly attractive buil- ding block is calix[4]resorcinarenes with eight pen- dant hydroxyl functional groups[2]. In a crystal engi- neering design strategy for molecular self-assembly, cocrystallization of C-methylcalix[4]resorcinarenes with nitrogen-donor molecules such as pyridines in the presence …     

1,4-二甲氧基柱[5]芳烃的合成及其与1,6-己二胺包结常数的测定

合成了1,4-二甲氧基柱[5]芳烃（DMP[5]）,采用核磁滴定方法研究了主体分子DMP[5]与客体分子1,6-己二胺的包结作用。通过摩尔比方法确定了主客体分子间的包结比为1∶1,并利用DynaFit计算了包结常数Ka=49 L/mol。本实验可作为有机化学实验在本科生化学及相关专业开设,有利于学生了解超分子化学前沿知识,激发学习兴趣,培养综合实验能力和科研方法。     

A Neutral Supramolecular Hyperbranched Polymer Fabricated from an AB2‐Type Copillar[5]arene

A heterotritopic copillar[5]arene monomer by introducing effective neutral guest moieties (methylene chains end‐capped with cyano and triazole groups) to a pillar[5]arene macrocycle is prepared. This well‐designed AB₂‐type copillar[5]arene contains strong host–guest recognition motifs that are connected with relatively flexible and long linkers, thus efficiently assembles to form supramole­cular hyperbranched polymer (SHP) in chloroform solution, which is characterized by various techniques including ¹H NMR, DOSY, viscosity, DLS, and TEM. Particularly, this supramolecular polymer can be effectively depolymerized by adding a competitive butanedinitrile guest.

     

Synthesis and Crystal Structure of p-tert-Butylthiacalix[8]arene: A New Member of Thiacalixarenes

Even though it was obtained in poor yield, p-tert-butylthiacalix[8]arene (TC8A) has been synthesized as a new member of thiacalix[n]arenes by the terephthalate-induced cyclization of a mixture of acyclic oligomers, which was obtained by the reaction between p-tert-butylphenol and sulfur with CaO in ethylene glycol/diphenyl ether system. Slow evaporation of the chloroform solution of TC8A afforded guest-free crystals consisting of TC8A itself. The close-packed crystal structure of TC8A resembles that of p-tert-butylcalix[8]arene (C8A) closely, containing a plated loop molecular structure.This revised version was published online in July 2005 with a corrected issue number.