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Metal‐encapsulated covalent organic frameworks (metal/COFs) represent an emerging paradigm in heterogeneous catalysis. However, the time‐intensive (usually 4 or more days) and tedious multi‐step synthesis of metal/COFs remains a significant stumbling block for their broad application. To address this challenge, we introduce a facile microwave‐assistedin situmetal encapsulation strategy to cooperatively combine COF formation andin situpalladium(II) encapsulation in one step. With this unprecedented approach, we synthesize a diverse range of palladium(II)‐encapsulated COFs (termed Mw‐Pd/COF) in the air within just an hour. Notably, this strategy is scalable for large‐scale production (~0.5 g). Leveraging the high crystallinity, porosity, and structural stability, one representative Mw‐Pd/COF exhibits remarkable activity, functional group tolerance, and recyclability for the Suzuki‐Miyaura coupling reaction at room temperature, surpassing most previously reported Pd(II)/COF catalysts with respect to catalytic performance, preparation time, and synthetic ease. This microwave‐assistedin situmetal encapsulation strategy opens a facile and rapid avenue to construct metal/COF hybrids, which hold enormous potential in a multitude of applications including heterogeneous catalysis, sensing, and energy storage.
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Dioxin-Linked Covalent Organic Framework-Supported Palladium Complex for Rapid Room-Temperature Suzuki–Miyaura Coupling Reaction
Covalent organic framework (COF)-supported palladium catalysts have garnered enormous attention for cross-coupling reactions. However, the limited linkage types in COF hosts and their suboptimal catalytic performance have hindered their widespread implementation. Herein, we present the first study immobilizing palladium acetate onto a dioxin-linked COF (Pd/COF-318) through a facile solution impregnation approach. By virtue of its permanent porosity, accessible Pd sites arranged in periodic skeletons, and framework robustness, the resultant Pd/COF-318 exhibits exceptionally high activity and broad substrate scope for the Suzuki–Miyaura coupling reaction between aryl bromides and arylboronic acids at room temperature within an hour, rendering it among the most effective Pd/COF catalysts for Suzuki–Miyaura coupling reactions to date. Moreover, Pd/COF-318 demonstrates excellent recyclability, retaining high activity over five cycles without significant deactivation. The leaching test confirms the heterogeneity of the catalyst. This work uncovers the vast potential of dioxin-linked COFs as catalyst supports for highly active, selective, and durable organometallic catalysis.
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- PAR ID:
- 10505326
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Crystals
- Volume:
- 13
- Issue:
- 8
- ISSN:
- 2073-4352
- Page Range / eLocation ID:
- 1268
- Subject(s) / Keyword(s):
- covalent organic framework (COF) dioxin-linked COF Pd(II) immobilization Suzuki–Miyaura coupling
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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