苏州大学石子亮团队报道了巨共轭大环的表面合成。 相关研究成果于2021年4月14日发表在国际顶尖学术期刊《德国应用化学》。

研究人员已经实现了由30个亚基组成的直径约7nm的巨大共轭大环的表面合成。该合成是从发生在热Ag（111）表面的分子前体的脱溴偶联作用引发的，从而导致拱形寡聚链和大环的形成。扫描隧道显微镜结合密度泛函理论揭示，由于位置选择性脱溴和不对称分子构象，这些产物是由平行分子亚单位之间的C-Ag有机金属键辅助的共价低聚物。在较高温度下热处理激活的连续环脱氢控制了大环化合物的最终共轭。

研究发现为π-共轭大环提供了一种新的设计策略，为有机纳米结构的精确合成开辟了新的机会。

附：英文原文

Title: On‐Surface Synthesis of Giant Conjugated Macrocycles

Author: Cunrui Fan, Bangjin Sun, Zhanbo Li, Jiwei Shi, Tao Lin, Jian Fan, Ziliang Shi

Issue&Volume: 2021-04-14

Abstract: We have achieved an on‐surface synthesis of giant conjugated macrocycles of diameter ~7 nm consisting of up to 30 subunits. The synthesis was initiated from a debrominative coupling of the molecular precursors occurring on a hot Ag(111) surface, leading to the formation of arched oligomeric chains and macrocycles. These products, revealed by scanning tunneling microscopy in combination with density functional theory, were covalent oligomers assisted by C‐Ag organometallic bonds between parallel molecular subunits, due to a site‐selective debromination and the asymmetric molecular conformation. A consecutive cyclodehydrogenation activated by thermal treatments at higher temperatures steered the final conjugation of the macrocycles. Our finding provides a novel design strategy toward π‐conjugated macrocycles, and opens up new opportunities for precise synthesis of organic nanostructures.

DOI: 10.1002/anie.202104090

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202104090