Han Qing, Li Zuo, Sun Kai, Tao Min-Long, Shi Ming-Xia, Yang Da-Xiao, Xia Jing-Xiang, Wan Jia-Jie, Wang Jun-Zhong
School of Physical Science and Technology & Chongqing Key Laboratory of Micro&Nano Structure Optoelectronics, Southwest University, Chongqing 400715, China.
Phys Chem Chem Phys. 2022 May 4;24(17):10292-10296. doi: 10.1039/d2cp00778a.
Chiral resolution is of fundamental importance to conglomerate or racemate crystallization. Here we demonstrate that the spontaneous chiral resolution of pentahelicene racemates occurred in the monolayer domains. When deposited on a Cd(0001) surface, pentahelicene molecules crystallize into a commensurate (6 × 6)0° structure built mainly from homochiral trimers. Spontaneous chirality separation takes place in the form of opposite mirror domains, where 2D enantiomorphism is not expressed by the oblique adlattice, but by the supramolecular chirality of the pentahelicene trimers. Furthermore, annealing the sample or extreme close-packing lead to the presence of lattice handedness through the formation of a porous network structure or an edge-on phase. These results provide valuable insight for 2D conglomerate crystallization and stereochemical recognition.
手性拆分对于聚集体或外消旋体结晶至关重要。在此我们证明，五螺烯外消旋体的自发手性拆分发生在单层区域中。当沉积在Cd(0001)表面时，五螺烯分子结晶成一种主要由同手性三聚体构成的共格(6×6)0°结构。自发的手性分离以相反的镜像区域形式发生，其中二维对映异构不是由倾斜的附加晶格表现出来，而是由五螺烯三聚体的超分子手性表现出来。此外，对样品进行退火处理或极度紧密堆积会通过形成多孔网络结构或边缘取向相而导致晶格手性的出现。这些结果为二维聚集体结晶和立体化学识别提供了有价值的见解。
