氧原子转移反应从孤立的 (oxo) (V) 环到硫化物
Anil Kumar1, Israel Goldberg, Mark Botoshansky
1Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Journal of the American Chemical Society
|October 12, 2010
概括
(V) 环作为有效的氧原子转移 (OAT) 剂,即使反应中间体不太可能. 化增强了它们的反应性和选择性,在OAT反应中与thioanisoles进行反应.
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.
- 反应机制 反应机制
背景情况:
- 卡罗尔是能够稳定金属复合体中的高氧化状态的宏循环连接体.
- 螺纹对催化应用很有兴趣,特别是在氧化反应中.
- 了解氧原子转移 (OAT) 的机制对于设计高效的催化剂至关重要.
研究的目的:
- 合成和表征新型的 (III) 和 (V) 角醇复合物.
- 为了研究 ((V) corroles与各种 thioanisole基质的OAT反应性.
- 阐明OAT过程的机械方面,包括化作用.
主要方法:
- 合成自由基,然后进行化和化.
- 用X射线结晶学测定关键珊瑚复合物的结构.
- 与臭氧的氧化产生 (((V) 角质,其特点是NMR光谱学和电化学.
- 反应性研究涉及用替代的安醇替代 OAT 的史泰基度反应.
主要成果:
- 合成和表征了十个 (III) 角,其中六个结构通过X射线晶体学确定.
- 隔离和特征十个 (oxo) ((V) corroles,具有低旋转,三重结合的Mn-O部分.
- 与非化类型相比,化 (氧) (V) 皮表现出显著增强的OAT反应性 (高达5倍).
- 哈梅特研究揭示了反应复合体的大负罗值,与电友性OAT一致.
- 较少反应复合体显示选择性降低和非第一阶动力学,表明不成比例的途径.
结论:
- (氧) (V) 环是有力且合法的氧原子转移剂.
- 在β-pyrrole位置的化增强了-氧部分的电友性和反应性.
- 反应性模式表明,直接OAT是反应复合体的主要机制,而不成比例变得与不太反应的物种有关.
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