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In this special issue, M. El-Kaderi and co-workers reported the synthesis of a redox-active pyrene-containing polyimide COF (PICOF-1) by linker exchange using an imine-linked COFs as a template (article 2200782). In order to improve the production efficiency of COFs, He and co-workers reported a "thermally promoted homogenous-floating-concentrating" strategy for the rapid synthesis of highly crystalline triazine/hydroxyl-rich COFs under mild conditions (article 2200786). Covalent organic frameworks (COFs) are a class of crystalline, porous polymers formed from the reversible covalent reactions between organic building blocks, resulting in ordered structure, permanent porosity, and topologically diversed. [Extracted from the article]

Tuning catalytic centers in heterogeneous catalyst, both in a chemical and a spatial manner, is a powerful approach to improve the stability and the efficiency of catalysts. While the chemical aspects are largely understood, the spatial interactions around active sites, comprised of non‐covalent interactions, are difficult to maintain and challenging to study. Herein, the unique properties of covalent organic frameworks (COFs) are utilized to establish an ideal reaction environment for the hydrolysis of cellobiose and other common disaccharides in mild, metal‐free, and neutral aqueous conditions. The chosen COF, HCl‐PSA‐IM‐COF‐OMe ("HCl" for hydrochloric acid, "PSA" for propyl sulfonic acid, "IM" for imidazole, and "OMe" for methoxy), is modified to be ultra‐stable in aqueous conditions and possesses sulfonic acid groups for general acid catalysis and for enhanced hydrogen bonding with reactants as well as intraporous chloride anions for oxocarbenium intermediate stabilization. In addition, the system also relies on the differences in adsorptive binding behavior, Kads, of the reactants and the products to the functionalized framework and benefits from a separate physical, kinetic process to boost the catalytic cycle. Due to its stability in aqueous conditions, HCl‐PSA‐IM‐COF‐OMe can be recycled and maintains its hydrolytic properties for five cycles before regeneration is needed. [ABSTRACT FROM AUTHOR]