替代性选择性氧化途径用于SiO2支持的Ru-单体复合催化剂上的化氧化和烯环氧化
Mizuki Tada1, Satoshi Muratsugu, Mutsuo Kinoshita
1Institute for Molecular Science, 38 Nishigo-Naka, Myodaiji, Okazaki, Aichi 444-8585, Japan. mtada@ims.ac.jp
Journal of the American Chemical Society
|December 17, 2009
概括
在SiO(2) 上的一种新型催化剂对选择性氧化和环氧化具有很高的活性. 这种支持的鲁单体复合物实现了异常高的氧化和环氧化转换率.
科学领域:
- 不同质的催化剂.
- 有机金属化学 有机金属化学
- 表面科学是一门科学.
背景情况:
- 开发高效和选择性的催化剂对于绿色化学至关重要.
- 复合物是已知的氧化反应的催化剂.
- 支持的催化剂在分离和可重复使用方面具有优势.
研究的目的:
- 为了准备和描述一种新型支持的单体复合物.
- 评估其对化物的选择性氧化和烯的环氧化的催化活性.
- 了解控制催化剂选择性和活性的因素.
主要方法:
- 一个p-cymene鲁单体复合体前体的合成.
- 复合物的固定在SiO(2) 表面上.
- 使用FT-IR,NMR,UV/vis,XPS,EXAFS和DFT计算进行表征.
- 使用O(2) 进行化氧化和烯环氧化催化试验.
主要成果:
- 在SiO上形成孤立的,不和的中心.
- 实现了异常高的营业额 ():3880万的异甲基氧化和2100万的跨乙烯环氧化.
- 在的存在下,选择性从化氧化转换到烯环氧化.
- 确定两个反应的激活能 (48kJ/mol用于IBA氧化,99kJ/mol用于环氧化).
结论:
- 在SiO(2) 上隔离的鲁单体复合物是一种高效的催化剂.
- 基的优先协调影响反应路径,有利于环氧化.
- 这项工作为高效的烯环氧化催化机制提供了洞察力.
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