(2-Methylcyclopenta[I]phenanthryl)(2)ZrCl2 and (2-phenylcyclopenta[I]phenanthryl)(2)ZrCl2 were synthesized and used, after activation with MAO, as catalysts for the polymerization of propene. The resulting polymers had low isotacticities (8-18% [mmmm]). Ligand rotation barriers for the corresponding Zr-dibenzyl derivatives were determined by dynamic NMR spectroscopy. Pathways and transition states for ligand rotation in this series of complexes were studied by molecular-mechanics calculations and are discussed in relation to the microstructure of the respective polymer products.
(2-甲基
环戊烯[I]
菲烷基)(2)ZrCl2和(2-苯基
环戊烯[I]
菲烷基)(2)ZrCl2被合成并使用后,经MAO活化,作为
丙烯聚合的催化剂。所得聚合物具有低等规度(8-18% [mmmm])。通过动态核磁共振光谱法确定了相应Zr-二苄基衍
生物的
配体旋转能垒。通过分子力学计算研究了该系列配合物中
配体旋转的路径和过渡态,并与相应聚合物产品的微观结构进行了讨论。