循环金属化铁的鉴定和反应性
Theresa E Boddie1, Stephanie H Carpenter1, Tessa M Baker1
1Department of Chemistry , University of Rochester , Rochester , New York 14627 , United States.
Journal of the American Chemical Society
|July 16, 2019
概括
研究人员在三醇辅助的C-H激活中确定了活性铁物种. 这种低旋铁 (II) 复合物是形成C-H arylation的循环金属化中间体的关键,促进有机合成.
科学领域:
- 有机金属化学
- 催化剂
- 合成有机化学
背景情况:
- 铁催化是有机转化的一个强大工具.
- 了解反应性铁物种对于开发C-H激活反应至关重要.
研究的目的:
- 确定在三醇辅助的铁催化C-H激活中活性的主要循环金属化铁物种.
- 使用铁催化剂阐明C-H化机制.
主要方法:
- 冷捕获的Mössbauer光谱
- 单晶X射线晶体学
- 反应性研究
主要成果:
- 活性中间体被确定为一种低旋转铁 (II) 复合物:[[A]-[dppbz]-[THF]-[Fe]-[μ-MgX]-[2]-[μ-MgX].
- 通过与二甲的反应形成一个循环金属化铁 (II) - .
- 这种物种的氧化产生了C-H结合产物.
结论:
- 这项研究提供了铁催化C-H激活中活性中间体的第一个直接实验定义.
- 转金属化是决定速度的步骤,而C-H激活则很容易.
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