碳化合物C-H键的热激活由一个烯合复合体启动
Stephen H K Ng1, Craig S Adams, Trevor W Hayton
1Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1.
Journal of the American Chemical Society
|December 5, 2003
概括
一个基复合物的温和热解产生过渡性中间体,激活溶剂C-H键,首选准在基中更强的sp2C-H键. 本研究详细介绍了C-H激活途径,并确定了参与这些反应的关键烯和烯中间体.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 反应机制 反应机制
背景情况:
- 有机金属复合物在催化和材料科学中至关重要.
- 了解C-H键激活是开发新合成方法的关键.
- 基复合体为C-H功能化提供独特的反应性概况.
研究的目的:
- 为了研究一个特定的基复合物的热解,CpW(NO)(CH(2)CMe(3))(eta(3)-H(2)CCHCMe(2)) (1).
- 阐明C-H键激活机制,并确定过渡性中间体.
- 探索C-H激活对不同碳化合物溶剂的选择性.
主要方法:
- 复合物1在各种碳化合物溶剂 (四甲,,,,p-,环,甲基环) 中的热解.
- 使用光谱方法 (NMR,IR) 进行反应产品的表征.
- 孤立复合物的X射线晶体分析.
- 机械和标签研究以确定中间产品.
主要成果:
- 综合体1经过热解产生过渡性C-H激活中间体.
- 选择性C-H激活溶剂分子,更喜欢在中更强的sp2C-H键.
- 确定作为关键中间体的烯 (A) 和乙二 (B) 复合物.
- 在溶剂中通过多个C-H激活事件形成化复合体.
结论:
- 热解CpW (NO) (CH) (CMe) (3) (eta) (3) -H (2)) (CCHCMe) (2)) 提供了一个产生反应性C-H激活中间体的途径.
- 该系统对激活更强的C-H键具有选择性,特别是在芳香系统中.
- 鉴定的中间体和反应途径为有机金属C-H功能化策略提供了洞察力.
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