为不对称的烯环氧化进行异构结构的形金属有机框架:通过控制框架连锁和变化开放通道大小来调整催化活性
Feijie Song1, Cheng Wang, Joseph M Falkowski
1Department of Chemistry, CB#3290, University of North Carolina, Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|October 13, 2010
概括
这项研究引入了新的合金属有机框架 (CMOF) 作为高效的异质催化剂,用于不对称的环氧化. 这些可回收的CMOF表现出可调节的孔径大小和高的反选择性,为可持续的催化提供了一个有希望的平台.
科学领域:
- 材料化学 材料化学
- 催化剂是一种催化剂.
- 超分子化学 超分子化学
背景情况:
- 开发高效的异质不对称催化剂对于可持续的化学合成至关重要.
- 金属有机框架 (MOF) 为催化应用提供可调节的结构.
- 基拉尔金属盐复合物是不对称的环氧化作用的有效同质催化剂.
研究的目的:
- 构建一系列具有原始立方网络拓的异构结构性金属有机框架 (CMOFs).
- 研究可调节的二碳酸盐支架和相互透模式对框架特性的影响.
- 在不对称的环氧化反应中评估合成的CMOF的催化性能.
主要方法:
- 在溶热条件下使用[Zn(4)(μ(4) -O) ((O(2) CR) ((6) ]二级建筑单元和合的Mn-Salen衍生二碳酸盐支架合成CMOFs 1-5 .
- 使用单晶X射线衍射,粉末X射线衍射 (PXRD),热重力学分析 (TGA) 和质子核磁共振 ((1) H NMR) 的表征.
- 使用CMOF作为异质催化剂对非功能化烯酸进行不对称的环氧化.
主要成果:
- 成功合成了五种CMOF,它们的透度不同 (不透,两倍和三倍),受溶剂大小和杆长度的控制.
- 在CMOF系列中证明了开放通道和孔径的系统变化.
- 在不对称的环氧化过程中达到高的催化活性和环氧选择性 (高达92% ee),反应速率取决于孔径大小.
- 在多个反应周期后展示了催化剂的可回收性和结构完整性.
结论:
- 合成的CMOF是高效的,可回收的异质催化剂,用于不对称的环氧化.
- 框架特性,包括孔径大小和相互透,可以通过修改二碳酸支架来系统调整.
- 这项工作表明了将同质催化剂纳入MOF结构的潜力,以创建先进的异质催化系统.
相关概念视频
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