具有C-H键氨基化能力的高旋铁伊米多复合物
Matthew J T Wilding1, Diana A Iovan1, Theodore A Betley1
1Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|August 5, 2017
概括
这项研究介绍了一种新型的铁 (I) 复合物作为一种多功能合成物. 它与亚化物反应,形成高自旋铁胺复合物,使C-H键功能化和氨化反应成为可能.
科学领域:
- 无机化学
- 有机金属化学
- 催化剂
背景情况:
- 铁复合物在催化和合成化学中至关重要.
- 具有独特电子特性的低旋转铁具有价值.
- 开发用于C-H功能化的新铁复合物是一个活跃的研究领域.
研究的目的:
- 合成和表征一种新的低旋铁 (I) 复合物.
- 研究铁复合物的与有机酸盐的反应性.
- 探索由此产生的铁体复合体在C-H键功能化的潜力.
主要方法:
- 从 (ArL) FeCl中合成低旋铁 (I) 复合物 (ArL) Fe.
- (ArL) Fe与阿达曼酸和梅西酸的反应形成铁胺复合物.
- 使用EPR,Mössbauer光谱,磁力测量和X射线衍射进行了表征.
- 动力学研究 (kH/kD),以阐明C-H氨化机制.
主要成果:
- 合成了一种具有分子内 η6 - 烯相互作用的低旋铁 (ArL) 复合物.
- 用化物处理产生了高旋转的三坐标铁模复合物, (ArL) Fe (NAd) 和 (ArL) Fe (NMes).
- 这些铁胺复合物表现出反应性,包括四化物形成,酸盐转移,H原子抽象和酸的分子间C-H氨基化,具有显著的动态同位素效应.
结论:
- 合成的铁复合物作为产生反应性铁物种的有效前体.
- 高旋转铁模复合体表现出多种反应性,特别是在C-H键功能化中.
- 对于C-H氨化反应,建议采用最大能量和轨道重叠的两步机制.
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