解读铁催化C-H氨化与有机化物:N2从稳定的有机化物复合物中裂变
Wowa Stroek1, Martin Keilwerth2, Lorraine A Malaspina1
1Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
Chemistry (Weinheim an der Bergstrasse, Germany)
|November 2, 2023
概括
研究人员合成了一种稳定的铁有机化合物复合物,这是C-H氨基化的一个关键中间体. 这种复合物通过二烯插入促进了C-N键形成,从而推进了催化C-H功能化方法.
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.
- 合成化学 合成化学
背景情况:
- 直接激活C-H键,形成C-N键是有合成价值的.
- 有机化物复合物是C-H氨基化反应性烯中间体的关键前体.
- 稳定的α-N协调性有机化物复合物,特别是与铁的复合物,很少见,尽管铁在C-H氨基化中的活性很高.
研究的目的:
- 为了合成和表征一个稳定的铁α-N协调有机化合物复合物.
- 为了研究自由和协调的有机酸盐之间的平衡.
- 为了阐明涉及烯中间体的C-H氨化机制.
主要方法:
- 使用[Fe(N(SiMe3)2) ]和亚达曼酸 (AdN3) 合成铁有机化物复合物.
- 使用X射线晶体学,红外,核磁共振和57Fe Mössbauer光谱学进行了表征.
- 光结晶学观察N2解离和中间体形成.
- 通过1H NMR和Mössbauer光谱学监测的溶液相反应性研究.
主要成果:
- 一个稳定的铁α-N协调性有机化物复合物被成功合成和表征.
- 发现有机化物在自由和协调状态之间处于快速平衡状态 (Keq = 62).
- 光结晶学揭示了N2解离和结构变化,这些变化表明烯的形成.
- 溶液研究证明了通过烯插入的催化C-H氨化,并观察到过渡的imido/nitrene中间体.
结论:
- 该研究报告了第一个稳定的铁α-N协调有机化合物复合物.
- 这种复合物作为铁催化C-H氨化反应的可行前体.
- 这些发现为涉及过渡性亚烯物种的C-H氨化机制提供了洞察力.
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