Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
J Am Chem Soc. 2020 May 6;142(18):8262-8269. doi: 10.1021/jacs.0c00624. Epub 2020 Apr 27.
A new type of macrocyclic arenes, named pagoda[4]arene () and pagoda[4]arene (-), were conveniently synthesized by the TFA-catalyzed one-pot condensation of 2,6-dimethoxylanthracene and paraformaldehyde in dichloromethane at room temperature. and showed unique square pagoda structures and fixed conformations in solution and also exhibited strong blue fluorescence. Moreover, and - with deep and rich-electron cavities could not only encapsulate -hexane and one or two dichloromethane molecules in the solid state but also showed strong binding abilities toward neutral dinitriles with different chain lengths and various nitrogen-containing heterocyclic salts to form 1:1 stable host-guest complexes in both solution and the solid state. In particular, it was also found that with the increase in the alkyl chain length of the dinitriles, the association constants for their complexes with both and - were markedly increased from glutaronitrile to octanedinitrile as a result of the deep cavities of the macrocycles and multiple intermolecular interactions. Since and had stable planar chirality, their efficient resolutions were further achieved by HPLC with a chiral column. Interestingly, the two enantiomers showed mirror-imaged CD signals and excellent CPL properties, which could allow them to have potential applications in chiral luminescent materials.
一种新型的大环芳烃，命名为方塔[4]芳烃()和方塔[4]芳烃(-)，可以通过 TFA 催化的 2,6-二甲氧基蒽和多聚甲醛在室温下于二氯甲烷中的一锅法缩合方便地合成。和在溶液中显示出独特的方形方塔结构和固定构象，并且表现出强的蓝色荧光。此外，具有深而富电子空腔的和不仅可以在固态下包封-己烷和一个或两个二氯甲烷分子，而且还表现出对具有不同链长和各种含氮杂环盐的中性二腈的强结合能力，以在溶液和固态中形成 1:1 稳定的主客体配合物。特别是，还发现随着二腈中烷基链长度的增加，由于大环的深腔和多种分子间相互作用，它们与和的配合物的结合常数从丁二腈到辛二腈显著增加。由于和具有稳定的平面手性，它们的高效拆分可以通过 HPLC 用手性柱进一步实现。有趣的是，两种对映异构体表现出镜像 CD 信号和优异的 CPL 性质，这使得它们有可能在手性发光材料中得到应用。
