金属离子决定铁的结构和反应性
Yafei Gao1, Maren Pink1, Jeremy M Smith1
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|January 25, 2022
概括
金属离子对铁的imido复合体有影响Fe=N键的长度和imido连接体的基本性. 这种协调指导反应,影响诸如原子转移和芬转化之类的反应.
科学领域:
- 有机金属化学
- 协调化学
- 无机化学
背景情况:
- 无氧化解金属离子被建议调节金属连接体多重键反应性.
- 这些系统的结构功能关系数据有限.
- 铁性复合物是各种催化循环中的关键中间体.
研究的目的:
- 研究金属离子对铁模复合物的结构和电子效应.
- 了解金属协调如何影响 imido 配体的反应性和随后的转化.
- 在像原子转移 (HAT) 这样的反应中建立铁基复合物的结构-活性关系.
主要方法:
- 通过X射线结晶学合成和对一系列Fe (II) imido复合物与协调金属 (Li,Na,K) 的结构特征.
- 实验研究包括质子化,化和与1,4-环二烯和二烯的反应.
- 分析电子结构的计算研究,Fe=N键的极化,和 imido 连接体的基本性.
主要成果:
- 获得了结构特征的Fe (II) imido复合体与协调的Li,Na和K离子.
- 金属协调会轻微延长Fe=N键,其效果与金属离子大小成反比例.
- 随着金属协调 (Li > K ≈ Na) 的增加,影响了HAT和烯反应的反应性.
结论:
- 金属离子协调在很大程度上决定了铁模联体的结构和反应性.
- 由金属协调调节的imido配体的基本性控制了反应路径和速度.
- 这些发现突显了金属在指导有机金属中间体的反应性方面的作用.
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