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用金属模板/金属交换方法对离散的Mn(II) 双复合物的共价异质化:一种具有增强反应性的环氧化催化剂
Tracy J Terry1, T Daniel P Stack
1Department of Chemistry, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|March 21, 2008
概括
使用金属模板方法在SBA-15上固定环氧化催化剂可以提高稳定性和选择性. 与随机接种或均质催化剂相比,这种模板式方法提供了更好的催化剂性能和循环利用.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 纳米技术纳米技术
背景情况:
- 在固体支上固定氧化催化剂提供了诸如场地隔离,增强稳定性和更容易回收等好处.
- 对于开发高效的环氧化催化剂,bis-1,10-phenanthroline连接物至关重要.
研究的目的:
- 开发一种合成金属模板方法,将bis-1,10-phenanthroline连接物 kovalently 连接到中孔性SBA-15上.
- 用这种模板方法评估使用这种模板方法固定的催化剂的环氧化反应性和性能.
主要方法:
- 采用金属模板/金属交换策略,在SBA-15上创建一个定义的协调环境.
- 印制的基被装满了来形成氧化催化剂.
- 催化剂性能与随机移植的类似物和使用烯酸与酸氧化氧化烯酸的同质催化剂进行了比较.
主要成果:
- 与随机接种相比,模板方法产生了更可重复的,类似溶液的bis-1,10-phenanthroline协调.
- 印制催化剂表现出更好的环氧选择性,更广泛的基质范围和更高的反应性.
- 模板催化剂表现出高效的回收和优异的性能,相比同质和随机移植的催化剂,显示出可变的反应性或降解.
结论:
- 在SBA-15上对bis-1,10-phenanthroline连接物的金属模板固定是一种可行的策略,用于创建高度活性和选择性的环氧化催化剂.
- 这种方法克服了随机接种和同质催化剂的局限性,在烯酸烯酸环氧化中提供了增强的稳定性,可回收性和效率.
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