在共价有机框架中的化学转换
Peter J Waller1, Steven J Lyle1, Thomas M Osborn Popp1,2
1Department of Chemistry, University of California-Berkeley , Materials Sciences Division, Lawrence Berkeley National Laboratory, Kavli Energy NanoSciences Institute at Berkeley, and Berkeley Global Science Institute, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|December 10, 2016
概括
研究人员通过直接氧化将二胺共价有机框架 (COF) 转化为更稳定的胺COF. 这种新的方法绕过了常见的合成挑战,产生具有永久透性和增强化学稳定的晶体材料.
科学领域:
- 材料科学
- 有机化学
- 纳米技术
背景情况:
- 共价有机框架 (COF) 是具有调节性特性的晶体多孔聚合物.
- 在COF中,氨基链接可能容易发生水解,从而限制其稳定性.
- 由于在框架内形成胺键的困难,直接合成胺氧化具有挑战性.
研究的目的:
- 开发一种将现有的 imine COF 转化为更稳定的 amide COF 的方法.
- 为了研究化学转化后的结晶性和多孔性.
- 展示一种难以直接合成的胺COF的新策略.
主要方法:
- 在预先合成的COF (TPB-TP-COF和4PE-1P-COF) 中直接氧化以形成胺链.
- 使用FT-IR和13C CP-MAS核磁共振光谱对得到的胺COF (1'和2') 的表征.
- 对结晶性和永久性孔隙性保留的评估.
主要成果:
- 通过完全氧化,成功地将胺基COF转化为同结构胺基COF.
- 由此产生的化物COF保持结晶性和永久性多孔性.
- 展示COF结合的第一个化学转换和绕过COF合成中的"结晶问题"的方法.
- 与它们的胺基前体相比,胺基COF具有更好的化学稳定性.
结论:
- 直接氧化提供了一种可行的途径,可以从imine COF合成稳定的胺基COF.
- 这种方法可以获得以前难以通过新合成获得的胺COF.
- 由此产生的化物COF具有增强的化学稳定性,并保留了诸如孔隙性等理想的结构特征.
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