在N2降解过程中,铁中碳键的形成机制
Samuel M Bhutto1, Reagan X Hooper1, Brandon Q Mercado1
1Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|February 16, 2023
概括
这项研究揭示了通过反应和气 (N2) 形成N-C键的机制. 它详细介绍了铁催化剂如何发生化和化迁移,从而使含有N的化合物合成.
科学领域:
- 有机金属化学
- 催化剂
- 固定气
背景情况:
- 一个先前的反应序列激活了中的C-H键和N2中的N-N三键,形成N-C键.
- 这一过程将丰富的原料转化为含有N的有机化合物.
- 通过化和化迁移形成N-C键的机制尚不清楚.
研究的目的:
- 阐明涉及和N2的N-C键形成的逐步机制.
- 了解在催化循环中减少,化和化迁移的作用.
- 研究关键中间体的电子结构和反应性.
主要方法:
- 介质物质的合成和结构特征.
- 磁性,光谱和运动研究.
- 密度功能理论 (DFT) 和CASSCF计算建模.
主要成果:
- 在aryl迁移之前,N2需要在距离处进行双重化.
- 一个涉及连续的基和离子的途径形成一个可分离的铁 (IV) -NN (SiMe3) 2中间体.
- 动力学研究证实了中间体到产品的第一阶段转化.
- DFT的计算显示出一个协调的过渡状态.
- 电子结构计算显示了Fe (II) /Fe (III) 状态和电友N原子的共振贡献.
结论:
- 已经确定了从和N2中形成N-C键的详细机制路径.
- 该机制涉及连续的化,形成独特的铁 (IV) 中间体和协调的化迁移.
- 这项工作为N2的功能化提供了一个新的有机金属策略.
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