由β-diketiminato ("Nacnac") 连接体框架支的阴阳甲基复合物
Paul G Hayes1, Warren E Piers, Robert McDonald
1Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, Canada.
Journal of the American Chemical Society
|March 7, 2002
概括
一种新型的复合物形成了高度活跃的基离子,用于乙烯聚合. 这些由激活的催化剂的性能与4组金属系统相美.
科学领域:
- 有机金属化学 有机金属化学
- 聚合催化法 聚合催化法
- 复杂的扫复合物
背景情况:
- 大量的β-diketiminato连接体稳定了无体金属复合物.
- 有机金属易斯酸如B,C,F,C,F,C,C,F,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,C,D,C,D,D,D,D,D,D,D,D,D,D,D,D,D,D,D,D,D,D) 对于激活金属前体至关重要.
研究的目的:
- 从二甲基复合物中合成和表征基酸.
- 在乙烯聚合过程中研究这些复合物的催化活性.
主要方法:
- 一个二甲基复合体与B的反应 (C) (6) (F) (5)) (3).
- 谱学表征 (NMR) 和X射线晶体学.
- 乙烯聚合试验. 乙烯聚合试验.
主要成果:
- 一个单离子的mu-甲基二聚和一个单离子的甲基离子的形成.
- 一个独特的 dicationic scandium 种类的特征.
- 乙烯聚合物的高催化活性,接近4组金属系统.
结论:
- 没有基的二甲基复合物作为催化活性酸盐的有效前体.
- 观察到的催化活性突出显示了3组金属在烯聚合中的潜力.
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