Dianion and Dication of Tetracyclopentatetraphenylene as Decoupled Annulene‐within‐an‐Annulene Models
Dianion and Dication of Tetracyclopentatetraphenylene as Decoupled Annulene‐within‐an‐Annulene Models
复制标题
四环戊四亚苯基的双阴离子和双阳离子作为解耦环烯 — 内环烯模型
DOI：
10.1002/anie.202115316
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Ie, Yutaka
中科院分区：
文献类型：
--
作者：
Miyoshi, Hirokazu;Sugiura, Ryosuke;Kishi, Ryohei;Spisak, Sarah N.;Wei, Zheng;Muranaka, Atsuya;Uchiyama, Masanobu;Kobayashi, Nagao;Chatterjee, Shreyam;Ie, Yutaka
四均基取代的四环戊四亚苯基（一种由交替的五元环和六元环组成的环烯）的双阴离子和双阳离子分别通过碱金属还原和卤化锑（V）氧化生成。理论上预测它们将采用双轮带结构，称为轮带内轮带模型，其中外部和内部共轭电路显着解耦。理论结构通过 X 射线晶体学分析得到实验证明，电子构型得到 MCD 谱的支持。基于 13C NMR 化学位移，显示负电荷和正电荷主要位于外周，表明双阴离子和双阳离子分别离域了 22-π 和 18-π 电子外周，以及内环的 8-π 电子结构。值得注意的是，二价阴离子具有开壳层特征，而二价阴离子具有闭壳层基态。
The dianion and dication of tetramesityl‐substituted tetracyclopentatetraphenylene, a circulene consisting of alternating five‐ and six‐membered rings, have been generated by reduction with alkali metals and oxidation with antimony(V) halides, respectively. They are theoretically predicted to adopt double annulenoid structures called annulene‐within‐an‐annulene models in which the outer and inner conjugation circuits are significantly decoupled. The theoretical structures were experimentally proven by X‐ray crystallographic analyses and the electronic configurations were supported by MCD spectra. Based on the13C NMR chemical shifts, negative and positive charges are shown to be located mainly at the outer periphery, indicating that the dianion and dication have delocalized 22‐π and 18‐π electron outer perimeters, respectively, and 8‐π electron structure at the inner ring. Notably, the dianion has an open‐shell character, whereas the dication has a closed‐shell ground state.