在和碳化合物的氧化化中使用高价值二化物
Agnideep Das1, Brendan Twamley1, Oscar R Kelly1
1School of Chemistry, Trinity College Dublin, The University of Dublin, College Green, Dublin 2, Ireland.
Angewandte Chemie (International ed. in English)
|December 17, 2024
概括
这项研究引入了一种新的催化剂,用于选择性化和碳化合物. 这项研究超越了传统的基于血的氧化方法,实现了高产量,并证明了选择性的C-H键功能化.
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.
- 有机合成 有机合成
背景情况:
- 含有Fe=O作为C-H氧化剂和Fe-OH反弹的heme范式指导了合成氧化催化剂的设计.
- 超越金属氧氧氧化剂和氧化物反弹,以更广泛的功能组合并存在限制.
- 和碳化合物的氧化化是一种重要的合成挑战.
研究的目的:
- 开发新的催化系统,用于超越已建立的模型的C-H功能化.
- 使用基催化剂探索和碳化合物的氧化化.
- 为了阐明催化C-H化过程的机制.
主要方法:
- 作为催化剂前体 (10mol%) 使用了二) 三甲酸盐 (CoII(OTf) 2.
- 使用的多牙N-捐赠体配体,如N,N'-二甲基-N,N'-二二二甲基) 乙-1,2-二胺 (BPMEN).
- 使用Selectfluor作为氧化剂和CsF作为增强化产量的添加剂.
- 使用光谱,动力和化学捕获技术研究反应机制.
主要成果:
- 在使用CoII/BPMEN/Selectfluor系统对和碳化合物的氧化化中取得了高产量.
- 在添加化 (CsF) 后,证明了近量产 (>90%) 的化产品.
- 在阿达曼坦衍生物 (1-基,1-基,1-碳基和1-胺基-阿达曼坦) 的3位选择性化.
- 提供了反对N-基机制的证据,支持CoIV-(F) 2物种作为活性氧化剂.
结论:
- 一个新的催化系统使和碳化合物的高效和选择性氧化化成为可能.
- 催化系统超越了传统的海姆模式,提供了更广泛的功能功能.
- 可能的活性氧化剂是CoIV-(F) 2物种,其中CoIII-F作为F原子供体.
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