Ester-Linked Crystalline Covalent Organic Frameworks
Chenfei Zhao1, Hao Lyu1, Zhe Ji1
1Department of Chemistry, Kavli Energy Nanoscience Institute, and Berkeley Global Science Institute, University of California-Berkeley, Berkeley, California 94720, United States.
Abstract:
Ester-linked, crystalline, porous covalent organic frameworks (COFs) have been synthesized and structurally characterized. Transesterification reactions between ditopic 2-pyridinyl aromatic carboxylates and tri- or tetratopic phenols gave the corresponding ester-linked COFs. They crystallize as 2D structures in kgm (COF-119) and hcb (COF-120, 121, 122) topologies with surface areas of up to 2092 m2/g. Notably, crystalline COF-122 comprises edges spanning over 10 phenylene units, an aspect that had only been achieved in metal-organic frameworks. This work expands the scope of reticular chemistry to include, for the first time, crystalline ester-linked COFs related to common polyesters.
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