浙江大学李昊团队提出了一种具有顺磁行为的自组装同手性自由基笼的策略。 相关研究成果发表在2021年3月2日出版的《德国应用化学》。

一个固有的C3对称的多氯三苯基甲基(PTM)自由基三醛与三(2 -氨基乙基)胺(TREN)缩合得到一个[4+4]四面体自由基笼，其外消旋对同手性对映体的分离率为75%。

通过X射线晶体学对其结构进行了表征，证实了每个笼骨架的同手性。分子内[CHπ]和笼状骨架内的氢键相互作用导致了同手性。笼中的四个PTM自由基经历了弱的空间耦合。磁性测量表明，每个笼子承受3.58转。

附：英文原文

Title: A self‐assembled homochiral radical cage with paramagnetic behaviors

Author: Tianyu Jiao, Hang Qu, Lu Tong, Xiaoyu Cao, Hao Li

Issue&Volume: 2021-03-02

Abstract: Condensation of an inherently  C  3  ‐symmetric polychlorotriphenylmethyl (PTM) radical trisaldehyde with tris(2‐aminoethyl)amine (TREN) yields a [4+4] tetrahedral radical cage as a racemic pair of homochiral enantiomers in 75% isolated yield. The structure was characterized by X‐ray crystallography, confirming the homochirality of each cage framework. The homochirality results from intramolecular [CHπ] and hydrogen‐bonding interactions within the cage framework. The four PTM radicals in a cage undergo weak through‐space coupling. Magnetic measurements demonstrated that each cage bears 3.58 spins.

DOI: 10.1002/anie.202100655

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202100655