竞争性C-I与C-CN从一个Rh (III) 复合体中减少性消除. 选择性是由溶剂控制的
Moran Feller1, Mark A Iron, Linda J W Shimon
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
Journal of the American Chemical Society
|October 14, 2008
概括
RhIII复合物通过两条路径选择性反应,这取决于溶剂的极性. 益基溶剂促进了乙尼的排出,而益基溶剂促进了化的排出和异尼的形成.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 反应机制 反应机制
背景情况:
- 通过氧化添加甲基化物来合成RhIII复合物[{PNP}Rh{CN}{CH3}[I] (5) 通过氧化添加甲基化物到[{PNP}Rh{CN}} (2) 中.
- 了解这种复合物的反应性对于开发新的催化工艺和材料至关重要.
研究的目的:
- 为了研究RhIII复合物的选择性反应途径[(PNP) Rh ((CN) ((CH3) ][I] (5).
- 阐明溶剂极性在指导反应结果中的作用.
- 了解电友对蓝色连接体的电友攻击机制.
主要方法:
- 合成的RhIII复合物[(PNP) Rh ((CN) ((CH3) ][I] (5).
- 复合物的反应在各种 aprotic 和 protic 溶剂与酸.
- 使用光谱技术和X射线衍射的产品的表征.
主要成果:
- 在近型溶剂中,甲基化物发生C-I还原性淘汰,随后对蓝配体进行电友性攻击,产生甲基异尼RhI复合物[(PNP) Rh (((CNCH3) ][I] (3).
- 在性溶剂中,乙基的C-C降解性消除发生,形成RhI复合物[(PNP) RhI] (9).
- X射线衍射证实了蓝联体和性溶剂之间的结,阻碍了电友性攻击.
结论:
- 溶剂决定RhIII复合物的反应路径,从而产生不同的RhI产物.
- 结合相互作用在调节蓝配体的反应性方面发挥着至关重要的作用.
- 这项研究提供了对有机金属化学中的选择性转换的见解.
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