在分子氧化催化过程中用有机金属复合物的前体转化
Ulrich Hintermair1, Stafford W Sheehan, Alexander R Parent
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
Journal of the American Chemical Society
|July 5, 2013
概括
在氧化催化剂中,Cp* (pentamethylcyclopentadienyl) 作为牺牲替代器连接体起作用. 它的损失形成了水和CH-氧化催化作用的活性蓝色二- (IV) 种.
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.
- 无机化学 无机化学 有机化学
背景情况:
- 同质氧化催化剂通常需要特定的连接体设计,以获得最佳的活性和稳定性.
- 复合物以其在氧化反应中的催化多功能性而闻名.
研究的目的:
- 为了研究Cp*连接体在[Cp*Ir(III) ((酸盐) X]氧化催化剂中的作用.
- 阐明活性催化物种的结构和反应性.
主要方法:
- 紫外线和1H NMR光谱学.
- 质谱仪 (MALDI-MS) 是一种质谱仪.
- 电泳,TEM-EDX,XPS,17O核磁共振,共振-拉曼光谱学等技术的使用.
- 密度函数理论 (DFT) 的计算.
主要成果:
- Cp*联结体迅速且不可逆转地丢失,形成活性蓝色溶液.
- 活性物种被确定为一个bis-μ-oxo di-iridium (IV) 复合体.
- 在没有诱导周期的情况下,二二 (IV) 复合物催化水和CH-氧化.
- DFT计算提供了对静止状态电子结构的洞察.
结论:
- Cp* 作为一个牺牲的取位器连接体,促进催化剂的激活.
- 已识别的二二 (IV) 种是一种稳定且高度活性的催化形式.
- [鱼甲酸]前体是氧化反应的有效前催化剂.
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