有孔的晶体联共价有机框架
Hao Lyu1, Christian S Diercks1, Chenhui Zhu2
1Department of Chemistry , University of California-Berkeley ; Materials Sciences Division, Lawrence Berkeley National Laboratory; and Kavli Energy NanoSciences Institute, Berkeley , California 94720 , United States.
Journal of the American Chemical Society
|April 25, 2019
概括
研究人员开发了COF-701,这是第一个未被替代的烯酸结合的共价有机框架. 这种坚固的材料具有多孔性,并且在固定易斯酸后保持催化活性,显示出化学应用的希望.
科学领域:
- 材料科学
- 有机化学
- 催化剂
背景情况:
- 共价有机框架 (COF) 为各种应用提供可调节的特性.
- 对于先进的材料设计,开发具有特定连接的强大的COF至关重要.
- 不被替代的烯酸结合具有独特的结构图案,提高了稳定性.
研究的目的:
- 合成和描述第一个未被替代的烯酸结合的共价有机框架 (COF-701).
- 评估新型COF的化学强度和多孔性.
- 通过固定一个易斯酸来证明COF的催化潜力.
主要方法:
- 在2,4,6-trimethyl-1,3,5-triazine (TMT) 和4,4'-biphenyldicarbaldehyde (BPDA) 之间发生阿尔多尔凝结反应.
- 福里埃变换红外光谱 (FT-IR) 和固态13C交叉极化魔方旋转 (CP-MAS) 核磁共振光谱用于结构确认.
- 在酸性和性条件下测量孔隙性和化学稳定性.
- 在迪尔斯-阿尔德反应中固定三乙烯酸 (BF3·OEt2) 和催化试验.
主要成果:
- 成功合成COF-701,具有未被替代的氨酸链接 (-CH=CH-).
- 在强酸性和基本性介质中,COF-701具有高孔径 (1715 m2 g-1) 和特殊的化学强度.
- 在基准迪尔斯-阿尔德反应中,在COF-701内固定BF3·OEt2 (BF3COF-701) 保持了催化活性.
结论:
- 作为首个未被替代的烯酸结合COF,COF-701是一个显著的进步.
- 氨酸结合的固有稳定性使框架具有显著的化学稳定性.
- BF3COF-701的多孔结构和保留的催化活性凸显了其作为可重复使用的异质催化剂的潜力.
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