A General Synthetic Strategy for the Synthesis of Imine-Linked Covalent Organic Frameworks in Choline Chloride–Hexafluoroisopropanol-Based Deep Eutectic Solvents

• DOI: 10.1021/acs.macromol.3c01258
• Publication Date: 2023-09-27T16:47:50Z
• Authors: Linlin Deng; Luchun Wang; Shaochi Liu; Qiuyi Liu; Junji Wang; Yongqing Tao; Meng Tian; Yulian Yang; Yuemeng Zou; Hong Niu; Dandan Wang; Die Gao
• Keywords: Imine; Choline chloride; Deep eutectic solvent

The imine-linked covalent organic frameworks (COFs) have garnered significant attention in various fields due to exceptional stability and polyamide structures, etc. However, the conventional synthetic protocols for high-crystallinity COFs often necessitate use of harmful solvent extra catalyst, rendering their synthesis environmentally detrimental. Therefore, it is imperative develop facile methods COF preparation that employ green solvents without need catalyst. Herein, an friendly, efficient, general strategy was developed synthesize five with high yield crystallinity by using choline chloride (ChCl)–hexafluoroisopropanol (HFIP) linked deep eutectic (DESs) as first time. Unlike other reactions required repeated exploration types crystallinity, as-developed method only changing molar ratio ChCl HFIP DES; can be synthesized. To further elucidate formation ChCl-HFIP-based DESs, COF-CH-1, which prepared 1,3,5-tris(4-aminophenyl)benzene (TPB) terephthalaldehyde (TPDD) precursors, regarded example. process COF-CH-1 preliminarily deduced on changes morphology, functional groups, element compositions, etc., change reaction temperature time optimal DES. Finally, according results, we also speculated possible role DESs COFs' formation.