Chen Hui, Tao Lei, Wang Dongfei, Wu Zhuo-Yan, Zhang Jun-Long, Gao Song, Xiao Wende, Du Shixuan, Ernst Karl-Heinz, Gao Hong-Jun
Institute of Physics, University of Chinese Academy of Science, Chinese Academy of Science, Beijing, 100190, P. R. China.
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 10087, P. R. China.
Angew Chem Int Ed Engl. 2020 Sep 28;59(40):17413-17416. doi: 10.1002/anie.202005425. Epub 2020 Aug 11.
The thermally induced cyclodehydrofluorization of iron tetrakis(pentafluorophenyl)porphyrin proceeded highly stereoselectively to give a prochiral product on a gold surface in an ultrahigh vacuum, whereas dehydrocyclization of the respective iron tetrakisphenylporphyrin did not show such selectivity. Stereoselectivity was predominantly observed for closely packed layers, which is an indication of intermolecular cooperativity and steric constraints induced by adjacent species. Density functional theory identified intermolecular packing constraints as the origin of such selectivity during the reaction. Scanning tunneling microscopy revealed the formation of an enantiomerically pure two-dimensional self-assembly as a conglomerate of mirror domains. On-surface two-dimensional topochemistry, as reported herein, may open new routes for stereoselective synthesis.
在超高真空中，四（五氟苯基）铁卟啉的热诱导环脱氟反应在金表面高度立体选择性地进行，生成一种前手性产物，而相应的四苯基铁卟啉的脱氢环化反应则没有表现出这种选择性。立体选择性主要在紧密堆积层中观察到，这表明相邻物种会诱导分子间协同作用和空间限制。密度泛函理论确定分子间堆积限制是反应过程中这种选择性的起源。扫描隧道显微镜揭示了作为镜像畴聚集体的对映体纯二维自组装的形成。本文报道的表面二维拓扑化学可能为立体选择性合成开辟新途径。
