Wydział Chemii , Uniwersytet Wrocławski , ul. F. Joliot-Curie 14 , 50-383 Wrocław , Poland.
PORT - Polski Ośrodek Rozwoju Technologii , ul. Stabłowicka 147 , 54-066 Wrocław , Poland.
J Am Chem Soc. 2019 May 8;141(18):7421-7427. doi: 10.1021/jacs.9b01797. Epub 2019 Apr 25.
A cycloparaphenylene-based molecular lemniscate (CPPL) was obtained in a short synthesis involving masked p-phenylene equivalents. The strained figure-eight geometry of CPPL is sustained by the incorporated 9,9'-bicarbazole subunit, which also acts as a stereogenic element. The shape of the distorted [16]cycloparaphenylene nanohoop embedded in CPPL is accurately approximated with a Booth lemniscate. The structure of CPPL, investigated using NMR and Raman spectroscopic methods, revealed strain-dependent features, consistent with the variable curvature of the ring. The electronic and optical properties of CPPL combine features more characteristic of smaller cycloparaphenylenes, such as a reduced optical bandgap and red-shifted fluorescence. CPPL was resolved into enantiomers, which are configurationally stable and provide strong chiroptical responses, including circularly polarized luminescence.
一种基于并环苯撑的分子双纽线（CPPL）通过包含掩蔽的对苯二酚等价物的短合成路线得到。CPPL 的扭曲 8 字形几何形状由掺入的 9,9'-联咔唑亚基维持，该亚基也作为一个手性中心。嵌入 CPPL 中的扭曲 [16]并环苯撑纳米环的形状与布斯双纽线精确吻合。使用 NMR 和拉曼光谱方法研究 CPPL 的结构，揭示了与环的可变曲率一致的应变依赖性特征。CPPL 的电子和光学性质结合了更小的并环苯撑更具特征的性质，例如降低的光学带隙和荧光红移。CPPL 被拆分成立体异构体，其构型稳定并提供强的手性光学响应，包括圆偏振发光。
