Heterocyclic Ring‐Opening of Nanographene on Au(111)
Heterocyclic Ring‐Opening of Nanographene on Au(111)
复制标题
Au(111)上纳米石墨烯的杂环开环
DOI：
10.1002/anie.202017137
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Kawai Shigeki
中科院分区：
文献类型：
--
作者：
Sun Kewei;Sugawara Kazuma;Lyalin Andrey;Ishigaki Yusuke;Uosaki Kohei;Taketsugu Tetsuya;Suzuki Takanori;Kawai Shigeki
环脱氢对于在退火时诱导贵金属表面上的分子的平面化是重要的。与许多通过形成碳-碳键合成多环芳烃的成功方法相比，在分子中进行碳-氮键的共轭和断裂的方法仍然很少。本文系统地研究了11，11，12，12-四苯基-1，4，5，8-四氮杂蒽醌二甲烷及其它三种衍生物在Au（111）上的C-N键的转变。利用键分辨扫描隧道显微镜，我们发现了一个吡嗪环与两个氮原子形成两个喹啉环的新的“杂环分离”反应，每个喹啉环都有一个氮原子。密度泛函理论计算表明，分子内的成环和开环的N-杂环的强烈影响的初始氢-底物相互作用。
Cyclo‐dehydrogenation is of importance to induce the planarization of molecules on noble surfaces upon annealing. In contrast to a number of successful syntheses of polycyclic aromatic hydrocarbons by forming carbon–carbon bonds, it is still rare to conduct conjugation and cleavage of carbon–nitrogen bonds in molecules. Here, we present a systematic transformation of the C−N bonds in11,11,12,12‐tetraphenyl‐1,4,5,8‐tetraazaanthraquinodimethane as well as three other derivatives on Au(111). With bond‐resolved scanning tunneling microscopy, we discovered novel the “heterocyclic segregation” reaction of one pyrazine ring with two nitrogen atoms to form two quinoline rings with one nitrogen each. Density functional theory calculations showed that the intramolecular ring‐forming and ‐opening of N‐heterocycles are strongly affected by the initial hydrogen–substrate interaction.