"离子碳":稀土金属甲基复合物的合成,结构特征和反应性
H Martin Dietrich1, Karl W Törnroos, Reiner Anwander
1Department of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway.
Journal of the American Chemical Society
|July 20, 2006
概括
新的有机金属集群产生无甲基烯复合物. 这些复合物促进了特贝式反应,并在聚合过程中表现出稀土金属的反应性.
科学领域:
- 有机金属化学 有机金属化学
- 稀土金属复合体 稀土金属复合体
- 聚合催化法 聚合催化法
背景情况:
- 合成了含有的多核集群,其配方为 {Cp*Y[(mu-Me) 2AlMe2](mu-Cl) }2和 {Cp*6La6[(mu-Me) 3AlMe]4(mu3-Cl) 2(mu2-Cl) 6}.
- 这些集群的特点是混合的甲基和化物桥接配体.
研究的目的:
- 为了合成新的"无"甲基利丁复合物.
- 研究这些新型复合物的甲基化和聚合反应中的反应性.
主要方法:
- 用托卢/THF溶液处理四甲基氨酸多核集群.
- 使用固态分析对由此产生的三核甲基利丁复合物的表征.
- 与子,化物和玛-瓦莱洛拉克顿的反应,以评估反应性.
主要成果:
- "没有"的甲基二烯复合物[Cp*3Ln3(mu-Cl) 3(mu3-Cl) ((mu3-CH2) ((THF) 3) (Ln = Y,La) 已成功生产出来.
- 这些复合体具有同结构,并包含一个经过绝缘屏蔽的施罗克型核性CH22-单元.
- 甲基二烯复合物显示了与碳化合物进行的特贝式甲基化和玛-瓦莱洛拉克的快速聚合.
结论:
- 合成的复合物代表了一类新的无甲基化合物.
- 核性甲基单元具有高度反应性,使得有效的甲基化反应成为可能.
- 观测到的玛-瓦莱洛顿的聚合突出显示了稀土金属在催化过程中的内在反应性.
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