快速的二氧化碳封存,激活和催化转化使用N-异环烯
Yan-Bo Wang1, Yi-Ming Wang, Wen-Zhen Zhang
1State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, People's Republic of China.
Journal of the American Chemical Society
|July 20, 2013
概括
N-异环烯酸 (NHOs) 有效地捕获二氧化碳,形成比NHC-CO2添加物更具反应性的添加物. 这些NHO-CO2 adducts在温和条件下有效催化CO2和propargylic酒精的循环碳酸盐合成.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 绿色化学 绿色化学
背景情况:
- N-异环碳 (NHCs) 是用于二氧化碳捕获的确立配体.
- 了解二氧化碳相互作用的替代N-异环结构对于开发新的催化系统至关重要.
研究的目的:
- 研究N-异环烯酸 (NHOs) 的二氧化碳封存能力.
- 探索有机合成中NHO-CO2添加物的催化活性.
- 为了比较NHO-CO2 adducts与NHC-CO2 adducts的反应性和稳定性.
主要方法:
- 进行X射线单晶分析以确定NHO-CO2 adducts的几何形状.
- 里埃变换红外光谱 (FTIR) 用于研究脱碳化.
- 使用NHO-CO2添加物进行氧化循环的催化反应.
- 标记实验以阐明反应机制.
主要成果:
- NHOs形成稳定的CO2附加物,具有曲的O-C-O几何形状 (127.7-129.9°).
- 与NHC-CO2添加剂相比,NHO-CO2添加剂表现出更容易的脱碳化.
- 在氧化循环反应中,NHO-CO2添加物具有显著更高的催化活性 (10-200倍).
- 在温和的条件下实现了α-alkylidene循环碳酸盐的选择性合成.
结论:
- 与NHC相比,NHO是有效的二氧化碳捕获剂,形成与NHC相比具有独特的结构和稳定性质的添加物.
- 在合成有价值的循环碳酸盐中,NHO-CO2添加物是利用CO2的高效催化剂.
- 增强的催化性能归因于CO2或产品从NHO-CO2 adducts中轻松释放.
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