Directing Molecular Weaving of Covalent Organic Frameworks and Their Dimensionality by Angular Control
Xing Han, Silvio Neumann, Brent L. Nannenga, Kaiyu Wang, Kelvin Kam-Yun Li, Saber Mirzaei, Xuan Yao, Chenhui Zhu, Mei‐Yan Gao, Yue‐Biao Zhang, Yong Cui, Omar M. Yaghi
Abstract
Although reticular chemistry has commonly utilized mutually embracing tetrahedral metal complexes as crossing points to generate three-dimensional molecularly woven structures, weaving in two dimensions remains largely unexplored. We report a new strategy to access 2D woven COFs by controlling the angle of the usually linear linker, resulting in the successful synthesis of a 2D woven pattern based on chain-link fence. The synthesis was accomplished by linking aldehyde-functionalized copper(I) bisphenanthroline complexes with bent 4,4'-oxydianiline building units. This results in the formation of a crystalline solid, termed COF-523-Cu, whose structure was characterized by spectroscopic techniques and electron and X-ray diffraction techniques to reveal a molecularly woven, twofold-interpenetrated chain-link fence. The present work significantly advances the concept of molecular weaving and its practice in the design of complex chemical structures.