近日，南方科技大学夏海平团队研究了四个芳香环通过原子相互嵌入策略融合形成四环体系。2025年4月14日出版的《美国化学会杂志》发表了这项研究成果。

芳香族化合物的骨架操纵已成为合成化学中的一种有力工具，但由于环和位点选择性的固有复杂性，同时进行多环操纵在很大程度上仍未得到探索。研究组报告了一种前所未有的多环骨架操纵，将四个5元芳香环融合成一种新型的金属桥接的6/6/6/6元环支架，其中包括两个有机芳香环和两个含金属芳香环系统。顺序环聚变是通过原子相互嵌入策略实现的；这种策略需要将两个氮原子逐步插入到单独的金属-碳键中，同时将一个金属原子整合为横跨两个异恶唑部分的桥梁。

中心金属原子的存在对于确保精确的底物排列和增强环和位点特异性至关重要。所得四六环产物表现出显著的稳定性和优异的近红外（NIR）功能特性，超过了前体化合物。这项工作不仅为设计易于复杂编辑的多功能底物分子奠定了概念基础，而且有助于对分子结构进行合理和针对性能的操纵。

附：英文原文

Title: Fusion of Four Aromatic Rings via an Atom-Mutual-Embedding Strategy to Form a Tetrahexacyclic System

Author: Fei-Hu Cui, Le-Han Gao, Kaidong Ruan, Fei Li, Meng Meng, Kexin Ma, Zhengyu Lu, Jiawei Fei, Huayu Tian, Liu Leo Liu, Yu-Mei Lin, Haiping Xia

Issue&Volume: April 14, 2025

Abstract: Skeletal manipulation of aromatic compounds has emerged as a potent tool in synthetic chemistry, but simultaneous multiring manipulation remains largely unexplored due to the inherent complexities of ring and site selectivity. Herein, we report an unprecedented multiring skeletal manipulation that fuses four 5-membered aromatic rings, comprising two organic and two metal-containing aromatic systems, into a novel metal-bridged 6/6/6/6-membered ring scaffold. The sequential ring fusion is accomplished through an atom-mutual-embedding strategy; this strategy entails the stepwise insertion of two nitrogen atoms into separate metal–carbon bonds and simultaneously integrates a metal atom as a bridge across two isoxazole moieties. The presence of a central metal atom is crucial for ensuring precise substrate alignment and enhancing both the ring and site specificity. The resulting tetrahexacyclic products exhibit remarkable stability and superior near-infrared (NIR) functional properties, surpassing those of the precursor compounds. This work not only establishes a conceptual foundation for designing versatile substrate molecules amenable to intricate editing but also contributes to the rational and performance-targeted manipulation of molecular architectures.

DOI: 10.1021/jacs.5c00697

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c00697