Chemical Conversion of Linkages in Covalent Organic Frameworks

作者：Peter J. Waller, Steven J. Lyle, Thomas M. Osborn Popp, Christian S. Diercks, Jeffrey A. Reimer, Omar M. Yaghi · 发表于：Journal of the American Chemical Society · 年份：2016 · DOI：10.1021/jacs.6b08377 · 被引用次数：606 · 研究领域：Covalent Organic Framework Applications、Metal-Organic Frameworks: Synthesis and Applications、Radioactive element chemistry and processing

The imine linkages of two layered, porous covalent organic frameworks (COFs), TPB-TP-COF ([C 6 H 3 (C 6 H 4 N) 3 ] 2 [C 6 H 4 (CH) 2 ] 3, 1 ) and 4PE-1P-COF ([C 2 (C 6 H 4 N) 4 ][C 6 H 4 (CH) 2 ] 2, 2 ), have been transformed into amide linkages to make the respective isostructural amide COFs 1′ and 2′ by direct oxidation with retention of crystallinity and permanent porosity. Remarkably, the oxidation of both imine COFs is complete, as assessed by FT-IR and 13 C CP-MAS NMR spectroscopy and demonstrates (a) the first chemical conversion of a COF linkage and (b) how the usual “crystallization problem” encountered in COF chemistry can be bypassed to access COFs, such as these amides, that are typically thought to be difficult to obtain by the usual de novo methods. The amide COFs show improved chemical stability relative to their imine progenitors.