Three-dimensional covalent organic frameworks (3D COFs) are promising crystalline porous materials, but the elucidation of their structure remains challenging, particularly for those featuring spiroborate linkages. Herein, we report the synthesis of a 3D crystalline COF with nbo topology, constructed from a rigid square-planar monomer, tetracyclopentatetraphenylene (TCTP), and spiroborate linkages. Theoretical calculations revealed that the TCTP core has higher rigidity than phthalocyanine, effectively suppressing structural fluctuations during framework formation. The structure of the resulting TCTP-COF was successfully determined using microcrystal electron diffraction (MicroED), revealing a noninterpenetrated cubic framework. TCTP-COF exhibits high crystallinity, thermal stability up to 320°C, and permanent porosity with a Brunauer-Emmett-Teller surface area of 1360 square meters per gram. This work represents the structural determination of a spiroborate-linked 3D crystalline COF using MicroED methods, providing a design strategy for expanding the chemical space of highly ordered 3D COF architectures.
The structural diversity and periodic arrangement of two-dimensional (2D) covalent organic frameworks (COFs) endow them with great promise for electronic and magnetic functionalities. Nevertheless, magnetic functionalities in semiconducting 2D COFs are not easily attainable due to the scarcity of effective topology dia...
Kai Xu, Yao-Qian Feng, Fuxiang Wen et al.· Angewandte Chemie· 0 citations
Highly crystalline semiconducting covalent organic frameworks (COFs) were synthesized from two isomeric tetrathienonaphthalene (TTN) nodes via transimination polymerization. The use of functionalized Schiff-base monomers proved critical for overcoming the low solubility of TTN-tetracarbaldehydes, enabling the solvoth...
Yuxuan Che, Ting Yu, Zhe-Chang He et al.· Chemistry of Materials· 1 citation
Covalent organic frameworks (COFs) are permanently porous, molecularly engineered scaffolds that exemplify the intersection of design, chemistry, and function. They are composed of organic monomers stitched together by covalent bonds into highly ordered two- or three-dimensional architectures. The majority of the studi...
Niyati Arora, Jessica Arcudia, Chamila S Bandara et al.· Chemical Science· 0 citations
Woven covalent organic frameworks (woven COFs) represent a rare class of mechanically interlaced crystalline polymers whose synthesis is largely limited by the availability of suitable linkage chemistry. Herein, we report the first example of a vinylene-linked woven covalent organic framework, constructed through a K...
Bidhan Kumbhakar, Sourav Ghosh, Uttam Pal et al.· Journal of the American Chem...· 0 citations
The development of fast proton-conducting materials that operate above 150°C with high chemical stability is both challenging and critically important for advancing proton-exchange membrane fuel cells (PEMFCs). In this study, we constructed two three-dimensional COFs with covalent phosphonate modification using a solve...
Aiping Yao, Lin-Lin Huo, Chunyi Sun et al.· Angewandte Chemie· 0 citations
