One-pot cascade construction of nonsubstituted quinoline-bridged covalent organic frameworks

Huaji Pang; Dekang Huang; Yanqiu Zhu; Xiaodong Zhao; Yonggang Xiang

doi:10.1039/d2sc06044b

One-pot cascade construction of nonsubstituted quinoline-bridged covalent organic frameworks

Chem Sci. 2023 Jan 6;14(6):1543-1550. doi: 10.1039/d2sc06044b. eCollection 2023 Feb 8.

Authors

Huaji Pang^{1

2}, Dekang Huang¹, Yanqiu Zhu^{1

2}, Xiaodong Zhao^{1

2}, Yonggang Xiang^{1

2}

Affiliations

¹ Department of Chemistry, College of Science, Huazhong Agricultural University Wuhan Hubei 430070 China ygxiang@mail.hzau.edu.cn.
² College of Resources and Environment, Huazhong Agricultural University 430070 Wuhan P. R. China.

Abstract

Irreversible locking of imine linkages into stable linkages represents a promising strategy to improve the robustness and functionality of covalent organic frameworks (COFs). We report, for the first time, a multi-component one-pot reaction (OPR) for imine annulation to construct highly stable nonsubstituted quinoline-bridged COFs (NQ-COFs), and that equilibrium regulation of reversible/irreversible cascade reactions by addition of MgSO₄ desiccant is crucial to achieve high conversion efficiency and crystallinity. The higher long-range order and surface area of NQ-COFs synthesized by this OPR than those of the reported two-step post-synthetic modification (PSM) facilitate charge carrier transfer and photogeneration ability of superoxide radicals (O₂˙^-), which makes these NQ-COFs more efficient photocatalysts for O₂˙^- mediated synthesis of 2-benzimidazole derivatives. The general applicability of this synthetic strategy is demonstrated by fabricating 12 other crystalline NQ-COFs with a diversity of topologies and functional groups.