组3化学中的多重C-H键激活:--甲集群的合成和结构特征
H Martin Dietrich1, Hilde Grove, Karl W Törnroos
1Department of Chemistry, University of Bergen, Allégaten 41, N-5007, Bergen, Norway.
Journal of the American Chemical Society
|February 2, 2006
概括
通过捐赠体诱导的Cp*Y(AlMe4) 2的裂变产生[Cp*Y(mu2-Me) ]3.3. 相反,与二甲基乙的反应导致C-H激活和--甲集群的形成,揭示了对有机金属活性的见解.
科学领域:
- 有机金属化学 有机金属化学
- 主群 化学 化学
- 催化剂是一种催化剂.
背景情况:
- 半金属烯复合体提供独特的反应途径.
- 基化合物是有机金属合成中的多功能前体.
- 供体-连接物相互作用显著影响金属-基键裂变.
研究的目的:
- 为了研究Cp*Y(AlMe4) 2与不同数量的乙烯的反应性.
- 探索基酸裂变和C-H激活的机制.
- 为了合成和表征新的-复合物.
主要方法:
- 在不同的士基测量条件下用乙烯对Cp*Y(AlMe4) 2进行处理.
- 使用像X射线晶体学这样的技术,对产生的复合体进行结构性表征.
- 分析涉及捐赠者诱导裂变和C-H键激活的反应途径.
主要成果:
- 完全切割Cp*Y(AlMe4)2与2等价的二甲基以太,获得95%的产量[Cp*Y(mu2-Me) ]3.
- 通过C-H激活,与二甲基以太的等分反应产生了低产量 (10-30%) 的[Cp*4Y4(mu2-CH3)2{(CH3)Al(mu2-CH3)2}4(mu4-CH) 2 .
- 在47%的产量中实现了异构八金属--甲集群的合成.
结论:
- 供体添加的固体几何学决定了反应途径:裂解与C-H激活.
- 预制的Y-CH3-Al部分容易被基本试剂抽取.
- 结构性特征证实了新型单 pentadienyl yttrium-aluminium 复合物的形成.
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