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Observation of Interpenetrated Topology Isomerism for Covalent Organic Frameworks with Atom-resolution Single Crystal Structures



Baoqiu Yu, Wenliang Li, Jing-Hong Li, Rui-Biao Lin, Hailong Wang, Xu Ding, Yucheng Jin, Xiya Yang, Hui Wu, Wei Zhou, Jingping Zhang, Jianzhuang Jiang


Rational control and understanding of isomerism are of significance but still remain a great challenge in reticular frameworks in particular for covalent organic frameworks (COFs) due to the complicated synthesis and energy factors. Herein, reaction of 3,3',5,5'-tetra(4-formylphenyl)-2,2',6,6'-tetramethoxy-1,1'-biphenyl (TFTB) with 3,3',5,5'-tetrakis(4-aminophenyl)bimesityl (TAPB) under different reaction conditions affords single crystals of two 3D COFs isomers, namely USTB-20-dia and USTB-20-qtz. Their structures with resolutions up to 0.91.1 Å have been directly solved by three-dimensional electron diffraction (3D ED) and synchrotron single crystal X-ray diffraction (SSXRD), respectively. USTB-20-dia and USTB-20-qtz show rare 2 × 2-fold interpenetrated dia-b nets and 3-fold interpenetrated qtz-b frameworks. Comparative studies in the crystal structures of these COFs and energetic difference theoretical simulation results indicate the crucial role of the flexible molecular configurations of building blocks in the present interpenetrated topology isomerism. This work not only presets the rare COFs isomers, but also gains an understanding of the formation of frameworks isomerism from both single crystal structures and theoretical simulations perspectives.
Journal of American Chemical Society


Porous Material, X-ray Diffraction, Electron Diffraction


Yu, B. , Li, W. , Li, J. , Lin, R. , Wang, H. , Ding, X. , Jin, Y. , Yang, X. , Wu, H. , Zhou, W. , Zhang, J. and Jiang, J. (2023), Observation of Interpenetrated Topology Isomerism for Covalent Organic Frameworks with Atom-resolution Single Crystal Structures, Journal of American Chemical Society (Accessed July 17, 2024)


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Created November 9, 2023, Updated January 4, 2024