近日，复旦大学周刚团队研究了稳定的二苯胺取代的三（2,4,6-三氯苯基）甲基自由基低聚物：合成、光学性质和氧化还原化学。2025年9月9日，《中国化学》杂志发表了这一成果。

以二苯胺基为主体，通过C-N / C-C偶联反应，研究组设计并成功合成了具有不同自旋中心数的三（2,4,6-三氯苯基）甲基（TTM）自由基低聚物。强分子内电荷转移（ICT）相互作用使自由基低聚物在近红外区域具有明显的吸收和发射带。令人印象深刻的是，TTM核心的强缺电子特性和相邻二苯胺间隔剂之间的单键连接模式极大地促进了分子内隔离氧化还原中心的形成。

据此，处理后的化学当量为NOSbF₆氧化剂中，多自由基直接转化为相应的最高氧化态，同时形成醌类化合物结构阳离子，这可以通过紫外光谱和单晶分析来验证。该研究为基于TTM的多自由基的构建提供了简便的设计规则，并为弱电子耦合体系下多自由基开壳分子的氧化过程和机理提供了参考。

附：英文原文

Title: Stable Diphenylamine-Substituted Tris(2,4,6-trichlorophenyl)methyl Radical Oligomers: Synthesis, Optical Properties, and Redox Chemistry

Author: Chuan Yan, Min Wang, Jing Fang, Si Liu, Weinan Chen, Xuefeng Lu, Gang Zhou

Issue&Volume: 2025-09-09

Abstract: Tris(2,4,6-trichlorophenyl)methyl (TTM) radical oligomers with different number of spin centers are designed and successfully synthesized through C–N/C–C coupling reaction using the diphenylamine group as building block. The strong intramolecular charge transfer (ICT) interactions endow radical oligomers with obvious absorption and emission bands in near-infrared regions. Impressively, the strong electron-deficient property of TTM core and single bond linking mode between the adjacent diphenylamine spacers greatly contribute to the formation of intramolecular isolated redox centers. Accordingly, after the treatment of chemical equivalent NOSbF6 oxidant, polyradicals are converted directly to the corresponding highest oxidation state along with the formation of quinoidal structure cation, which can be verified by UV spectra and single crystal analysis. This study develops a facile design rule for the construction of TTM-based polyradicals and provides the reference for oxidation process and mechanism of polyradical open shell molecules with the weak electron coupling systems.

DOI: 10.1002/cjoc.70269

Source: https://onlinelibrary.wiley.com/doi/10.1002/cjoc.70269