A Type of Halogen-Bonded Organic Frameworks Based on N⋯Cl + ⋯N Bonds: Stabilizing Sensitive Species

Open AccessCCS ChemistryRESEARCH ARTICLES17 Aug 2025A Type of Halogen-Bonded Organic Frameworks Based on N⋯Cl+⋯N Bonds: Stabilizing Sensitive Species Xuguan Bai, Zhennan Tian, Hongqiang Dong, Jiahao Zhao, Qiaoyan Qi, Shixing Lei, Mao Sun, Min Wei, Jianrong Zeng, Shangming He, Jia Tian, Lu Wang, Jike Wang, Haohu Li and Shigui Chen Xuguan Bai , Zhennan Tian , Hongqiang Dong , Jiahao Zhao , Qiaoyan Qi , Shixing Lei , Mao Sun , Min Wei , Jianrong Zeng , Shangming He , Jia Tian , Lu Wang , Jike Wang , Haohu Li and Shigui Chen https://doi.org/10.31635/ccschem.025.202506172 SectionsSupplemental MaterialAboutPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareFacebookTwitterLinked InEmail It remains a significant challenge to explore halogen bonds based on chlorine, despite extensive investigation into those involving larger halogen atoms like iodine and bromine. [N⋯Cl⋯N]+ halogen bond was usually unstable and typically only obtainable at extremely low temperatures (approximately −80 °C) due to chlorine's high electronegativity. In this work, we demonstrated the inaugural construction of stable chlorine(I)-bridged two-dimensional (2D) halogen-bonded organic frameworks (XOFs) utilizing sensitive [N⋯Cl⋯N]+ halogen bonds. The formation of XOF(Cl)-TPy-BF4/OTf was investigated using 1H NMR, XPS, IR, HR-TEM, and SEAD, PXRD, SAXS, exhibiting their good crystallinity. Unlike the highly unstable Py2ClBF4, XOF(Cl) displayed remarkable chemical and thermal stability, even maintaining the periodic framework integrity across various organic solvents. Moreover, the XOF(Cl) can be utilized as a platform to stabilize and immobilize the reactive Pd(0) clusters among the frameworks. The resulting XOF(Cl)-TPy-Pd0 demonstrated excellent catalytic activities in various Pd-catalyzed coupling reactions, including Suzuki, Heck, and Sonogashira couplings, affording high yields even under ambient conditions. Importantly, the synthesis of industrially relevant biphenyl-based liquid crystal molecules using XOF(Cl)-TPy-Pd0 resulted in no detectable palladium residue and the catalyst could be easily recovered via simple filtration and recycled multiple times with consistent catalytic performance. This work not only advances our understanding of chlorine(I) chemistry but also establishes a new strategy for the design and development of stable halogen-bonded organic frameworks. The successful demonstration of XOF(Cl) as a robust platform for stabilizing and utilizing reactive species highlights its promising potential for applications in catalysis and beyond. Download figure Download PowerPoint Previous articleNext article FiguresReferencesRelatedDetails Issue AssignmentNot Yet AssignedSupporting Information Copyright & Permissions© 2025 Chinese Chemical Society Downloaded 0 times PDF downloadLoading ...