通过迈克尔加法消除结合共价有机框架
M Rajeswara Rao1, Yuan Fang1,2, Steven De Feyter2
1Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada.
Journal of the American Chemical Society
|January 17, 2017
概括
研究人员使用了新的迈克尔加法-消除反应开发了新的二维π合共价有机框架 (COF). 这些材料具有可调节的电子特性,可以检测爆炸物,扩大COF的应用.
科学领域:
- 材料科学
- 有机化学
- 聚合物化学
背景情况:
- 动态共价化学对于制造复杂材料至关重要,比如共价有机框架 (COF).
- 目前用于π结合COF的合成方法,主要是希夫基凝结,是有限的,产生中度电子移位和易受水解的材料.
- 现有的因胺结合COF具有有限的特性和稳定性,阻碍了更广泛的应用.
研究的目的:
- 引入一种新的动态聚合方法,用于合成新的二维 (2D) 协价有机框架 (COF).
- 探索这些新合成的COF的电子和光学特性.
- 展示这些COF在传感应用中的潜力,特别是对于爆炸物.
主要方法:
- 在结构多样化的β-基醇和氨基之间利用迈克尔的添加-消除反应进行聚合.
- 合成的晶体粉末和2D π 结合的微米尺寸的薄膜.
- 通过减少带间隙 (1.8-2.2 eV),固态发光和电化学剂来表征COFs的π-结合.
主要成果:
- 通过新的动态聚合途径成功制备了新的2D π结合COF.
- 观察到显著减少带间隙,固态发光,并在电化学兴奋剂中形成中间极子状态.
- 通过光灭证明了对电子移位和三三氧化物 (TATP) 的直接检测的质子控制.
结论:
- 新的迈克尔添加-消除反应为具有可调节性质的高级π结合COF提供了多功能合成途径.
- 这些新型COF表现出增强的电子移位,发光和电化学活性.
- 开发的COF显示出对TATP等爆炸物的敏感检测的希望,并通过质子化提供可调节的电子特性.
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