Crystalline and Stable Benzofuran-Linked Covalent Organic Frameworks from Irreversible Cascade Reactions

Abstract

We report the synthesis of crystalline two-dimensional covalent organic frameworks (COFs) by connecting hydroxybenzene-aldehyde and acetonitrile building blocks to form cyano-substituted benzofuran linkages. Unlike the majority of COFs that were synthesized based on condensation reactions, the COFs in this report are crystallized from irreversible cascade reactions involving consecutive cyanide migration, ring-closure, and oxidation reactions. The irreversible property endows the COFs with high chemical stability in both acid and base and allows them to be postsynthetically modified to install predesigned functionality under harsh conditions. We highlight that the functionalized COFs serve as exceptional vehicles for superprotonic conductions.

In situ construction of redox-active covalent organic frameworks/carbon nanotube composites as anodes for lithium-ion batteries

“…Covalent-organic frameworks (COFs), a new class of crystalline porous polymers with a high surface area, long-range ordered structures, and adjustable functionalization, are distinctly different from traditional polymers. [16][17][18][19][20][21][22] Besides, COFs are connected by covalent bonds with rigid and extended frameworks, which thus displayed excellent stability in various solvents including organic electrolytes compared with small organic molecules. [23][24][25][26] Moreover, the uniform open channel of COF networks is benecial for the electrolyte infusion and ion/ electron transport.…”

Manipulating Grain Boundary Defects in π‐Conjugated Covalent Organic Frameworks Enabling Intrinsic Radical Generation for Photothermal Conversion

“…In this work, we adopted the previously established π-conjugated COFs (GS-COF-1 and GS-COF-2, Figure 1b) [12] as model materials. The phenol groups of the monomers Z. Chen, Y. Su, X. Tang, X. Zhang, C. Duan, F. Huang, Y. Li Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640, P. R. China E-mail: msfhuang@scut.edu.cn; celiy@scut.edu.cn…”

All sp2 carbon covalent organic frameworks

“…Topology diagram: the scheme in which monomers are designed to possess specific geometries so that their connections enable the growth of extended polygonal architectures. hexagonal frameworks (Figure 1A) [13,18,21,[29][30][31][32][33][34][35]. The [C 4 + C 2 ] combination with a C 4 -symmetric knot and C 2 -symmetric linker generates tetragonal frameworks so that the polymer backbones extend along both the x and y directions (Figure 1B) [20,36].…”