Construction of Covalent‐Organic Frameworks (COFs) from Amorphous Covalent Organic Polymers via Linkage Replacement

Abstract

Covalent-organic frameworks (COFs) as porous crystalline materials show promising potential applications. However,d eveloping facile strategies for the construction of COFs directly from amorphous covalent organic polymers (COPs) is still agreat challenge.T othis end, we report anovel approach for easy preparation of COFs from amorphous COPs through the linkage replacement under different types of reactions.F our COFs with high crystallinity and porosity were constructed via the linkage substitution of polyimide-linked COPs to imine-linked COFs as well as imine-linked COPs to polyimide-linked COFs.T he realization of the linkage substitution would significantly expand the researchs cope of COFs.

Single‐Pore versus Dual‐Pore Bipyridine‐Based Covalent–Organic Frameworks: An Insight into the Heterogeneous Catalytic Activity for Selective CH Functionalization

“…[24][25][26][27] The structure-function relationship of frameworks depends on the versatile synthetic strategy, network topology, heterogeneous linker exchange, binding functionalities, and flexible regulation of pore size/volume. [28][29][30][31][32][33][34] The tunability of structural properties along with high surface area, chemical and thermal stability make COFs one of the most promising candidates for catalysis, [35][36][37][38][39] gas storage/separation, [40][41][42][43][44][45] environmental remediation, [46][47][48] optoelectronics, [49][50][51] energy storage, [52][53][54][55] biomedical, [56][57][58] atmospheric water harvesting, [59] and chemosensor. [60] The cooperative assistance of pore size, pore shape, and binding sites in the COFs skeleton facilitates docking of catalysts to investigate fundamental organic conversions.…”

Conquering the crystallinity conundrum: efforts to increase quality of covalent organic frameworks

“…Crystalline COFs could also be prepared by linkage type substitution from amorphous porous organic polymers (POPs). 198 In a first step, imine and imide linked POPs were prepared, to which dialdehydes and dianhydrides were added respectively. When these mixtures were put in typical COF growth conditions for the desired linkage type, crystalline COFs were obtained (Fig.…”

Expeditious synthesis of covalent organic frameworks: a review

“…It is worth mentioning that such amorphous-to-crystalline transformation paves new avenues in the synthesis of crystalline COFs from amorphous polymers. [27][28][29][30][31] To date, mechanistic investigations on the nucleation and growth of COF are solely limited to boronate ester and imine-linked COFs. In light of the rapidly rising number of new linkages (over 20 in total), 32 an in-depth insight into the crystallization process of new COFs is a necessity.…”