碳化合物的C-H键激活由一个imidozirconocene复合体
Helen M Hoyt1, Forrest E Michael, Robert G Bergman
1Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|January 30, 2004
概括
新的二甲复合物激活了基和基中的多种碳键. 在C-H激活的突破为化学家提供了新的合成可能性.
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.
- 在C-H激活激活.
背景情况:
- 单质伊米多齐尔科诺复合物 (Cp2(L) Zr=NCMe3) 激活基C-H键,但不能激活和碳化合物.
- 之前没有观察到C-H在 imidometallocene系统中的激活.
研究的目的:
- 为了研究一种新型 imidometallocene 复合物的 C-H 键激活能力.
- 探索这种新类化合物的C-H激活的范围和选择性.
主要方法:
- 合成一种种族性乙烯基二四) 乙烯基甲三-丁胺复合物.
- 加热复合物以形成M=NR键.
- 与各种n-基,基和基的反应.
- 涉及甲分子内消除和协同添加C-H键的机制研究.
主要成果:
- M=NR键清洁地和定量地激活n-alkane,alkene和arene的C-H键.
- 在热力学上,sp2 C-H 键的激活比sp3 C-H 键的激活更稳定.
- 主要的C-H激活比次要的C-H激活更受欢迎.
- 热力学选择性似乎是以固态方式控制的.
结论:
- 伊米多甲烯复合物代表了用于广泛的C-H激活的新类催化剂.
- 观察到的选择性为控制C-H激活反应提供了洞察力.
- 这项工作扩大了有机金属复合物的合成化学中的实用性.
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