在三坐标铁 (II) 碳化合物复合体中,正常到异常的重新排列和NHC激活
Benjamin M Day1, Thomas Pugh, Daniël Hendriks
1School of Chemistry, The University of Manchester , Manchester, M13 9PL, U.K.
Journal of the American Chemical Society
|August 28, 2013
概括
加热正常的铁-N-异环碳化合物 (NHC) 复合物产生了罕见的异常铁-aNHC结构. 一个 tert-butyl 替代复合物通过 C-H 和 C-N 激活通路进行热分解.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 催化剂是一种催化剂.
背景情况:
- 在有机金属化学中,N-异环碳 (NHCs) 是多功能联体.
- 铁复合物与NHC连接体具有兴趣,因为铁的丰富性和低毒性.
- "正常"和"异常"NHC协调模式之间的区别对于理解反应性至关重要.
研究的目的:
- 为了研究一个正常的三坐标铁-NHC复合物的热重组.
- 为了合成和表征一种罕见的异常铁-aNHC复合物.
- 为了探索 tert-butyl 替代铁-NHC 复合物的热分解路径.
主要方法:
- 铁-NHC复合物的合成和表征.
- 热处理 (加热) 复杂的.
- 谱分析 (例如,NMR) 和X射线晶体学以确定结构.
主要成果:
- 正常的铁-NHC复合物[IPrFeN′′]2在加热时重新调整为其异常的模拟物[aIPrFeN′′2].
- 这种重新排列提供了一个罕见的三坐标异常铁-aNHC复合物的例子.
- 甲基-基替代复合物[(I(t) Bu) Fe((N′′) 2通过热分解形成一个bis(imidazole) 复合物[((t) BuIm) 2Fe(N′′) 2).
- 为分解提出了一种涉及连续激活C-H和C-N键的机制.
结论:
- 热条件可以诱导铁复合体中的正常NHC连接体重新排列为异常NHC连接体.
- 异常的铁-aNHC复合体,特别是三坐标复合体,是可访问的.
- 某些铁-NHC复合物的热分解可以通过新的C-H和C-N激活途径进行,从而产生意想不到的产品.
相关概念视频
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