冠芳烃是由杂原子与对位取代的芳(杂)环交替连接形成的大环分子。通过对芳环单元与桥连原子的种类与多寡的控制，可以调节其大环空腔的大小、形状与电性，实现对多种客体的识别，在物质运输、超分子催化、选择性分离等领域有很好的应用前景。本博士论文在已有研究的基础上，针对目前冠芳烃大环在结构与功能上的局限性，基于四嗪环在合成、反应与超分子化学中的独特性质，设计并合成了一系列结构新颖的含四嗪环的冠芳烃类大环分子，并研究了它们的性质。3,6-二氯四嗪是一种高活性的连接子，可以用于构建具有复杂结构的大环分子。目前的冠芳烃都是高对称性的分子，不具有手性。我们从廉价的对苯二酚与二溴苄出发，通过(3+1)片段偶联法高效构建了具有面手性的同冠[4]芳烃。再以3,6-二氯四嗪为连接子，通过再一次的(3+1)片段偶联法合成了具有复杂拓扑结构的手性螺环冠芳烃与双螺环冠芳烃。这类新型大环分子具有良好的手性光学性质。螺环冠芳烃还可以与四硫富瓦烯形成结构多样的主客体复合物单晶。四嗪参与的IEDDA反应十分高效，含四嗪环的冠芳烃是构建新型杂杯芳烃和环带分子的重要而独特的前体。在冠[3]芳烃[3]四嗪的苯环上引入氰基取代基，通过使氰基与相邻的四嗪环发生分子内IEDDA反应生成1,2,4-三嗪环，实现了“跨湾筑桥”策略从冠芳烃合成新型杯[3]芳烃。我们还尝试了基于杯[3]芳烃骨架进一步将其转化为环带分子的反应。四嗪是一种良好的阴离子-π受体，然而氧、硫原子桥连的冠芳烃不够稳定，无法实现亲核性阴离子的识别。我们利用对苯二乙腈和肼的一锅法反应合成了具有桶装空腔的亚甲基桥连冠[n]芳烃[n]四嗪 (n = 2-4)。其中冠[2]芳烃[2]四嗪可以选择性识别氟离子。通过紫外-可见滴定的手段研究了主客体间的识别作用，并通过顺磁滴定等手段指出氟离子水解出的氢氧根会诱导四嗪自由基阴离子的生成。总之，我们利用四嗪环在合成、反应与超分子化学中独特的性质，制得了具有多样化结构的冠芳烃，探明了新型大环化合物的光物理与分子识别性质，为丰富和发展冠芳化学提供了新的思路与方向。
Coronarenes are marcocycles composed of heteroatoms and p-(het)arylenes in an alternative fashion. The tunable macrocyclic geometries, cavities, and electronic features render coronarenes selective hosts in the application of molecular recognition, selective separation, transportation, supramolecular catalysis, etc. Aiming to expand their applications, this thesis focuses on the design and synthesis of novel coroanrenes based on the unique physical and chemical properties of tetrazines.3,6-Dichlorotetrazine is a highly reactive aromatic compound which has been widely used in the construction of complicated macrocycles. Till now, coronarenes reported in the literature are highly symmetrical molecules which do not have chirality. The first part of the thesis describes initially the synthesis of homo i-corona[4]arenes with planar chirality by means of a (3+1) fragment coupling reaction starting with inexpensive hydroquinone and bis(bromomethyl)benzene derivatives. Sequentially, taking the advantage of the high reactivity of 3,6-dichlorotetrazine, macrocyclization featuring another (3+1) approach proceeded efficiently to produce chiral spirophanes and dispirophanes which contain ditopic and polytopic cavities. The resolved enantiopure marcocycles exhibit dissymmetry factors around 10-3 for circular dichroism and circularly polarized luminescence. Having an eletron-deficient cavity, spirophanes serve as hosts to form complex with tetrathiafulvalene through lone pair-π and π-π interactions.Tetrazines are reactive hetereodiene of IEDDA reactions. Tetrazine-embedded coronarenes are therefore important and unique precursors for constructing novel hetercalixaromatics and beltarenes. Starting from 2,5-dicyano 1,4-hydroquinone or 1,4-phenylene dithiol, we synthesized cyano-bearing O6- or S6-corona[3]arene[3]tetrazines. Successful three-fold intramolecular IEDDA reactions between cyano groups and the adjacent tetrazines afforded unprecedented calix[3]arenes via the “fjords-stitching” strategy. Further transformation from calix[3]arenes to beltarenes was also explored experimentally and computationally.Tetrazine ring acts as an effective anion-π receptor owing to anion-π interactions. However, oxygen and sulfur-bridged corona[n]arene[n]tetrazines are not stable when anions are strong nucleophilic. To solve this problem, methylene-linked corona[n]arene[n]tetrazines (n = 2-4) with cylindrical cavities were synthesized via a one-pot reaction of p-phenylenediacetonitrile and hydrazine monohydrate. An unprecedented example of very selective fluoride recognition by a box-like corona[2]arene[2]tetrazine was revealed by UV-visible titration study. Based on EPR evidences and DFT calculations, the hydroxide generated from the interaction of fluoride ions with moisture would lead to the generation of tetrazine radical anions.In summary, utilizing unique properties of tetrazines in synthesis and supramolecular chemistry, we have developed a diversity of tetrazine-embedded coronarenes of sophisticated structures. We have also explored their photophysical and molecular recognition properties. Our study provides not only a deep insight into the chemistry of tetrazine-doped coronarenes but also opens new directions of the study of macrocyclic and supramolecular chemistry.
