阴离子,中性和阴离子双胺酸铁基复合物的合成和电子结构:评估单元乙烯聚合催化剂的氧化还原活性
Aaron M Tondreau1, Carsten Milsmann, Andrew D Patrick
1Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|October 2, 2010
概括
研究人员用二氧化 (imino) 皮里丁配体合成了铁基复合物. 他们发现,连接体电子特性和基组定位的变化可以调整铁中心.
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.
- 材料科学 材料科学 材料科学
背景情况:
- 铁基复合物 bis ((imino) pyridine 是已知的乙烯聚合的单组分催化剂.
- 了解这些复合物的电子结构对于优化催化活性至关重要.
研究的目的:
- 为了制备和表征阴离子,中性和阴离子 bis ((imino) pyridine 铁基复合物.
- 使用各种光谱和衍射技术,确定这些复合物的电子和分子结构.
- 为了将电子结构与它们与烯聚合催化剂的相关性相关联.
主要方法:
- 铁基复合物的化,中性和阳离子 bis ((imino) pyridine 的合成.
- 用X射线衍射来确定分子结构.
- 用于电子结构分析的Mössbauer光谱学和磁化学.
- 开放密度函数理论 (DFT) 计算用于计算洞察力.
主要成果:
- 阴离子复合体是高旋转的铁 (S(Fe) = 2),具有中性,无氧化解氧化 bis(imino) 皮里丁连接体.
- 一个电子的还原产生的中性基与bis(imino) 皮里丁基离子反铁磁结合高旋转铁离子.
- 进一步降低到阴离子复合体的结果是低旋转的铁中心 (S(Fe) = 0) 与封闭外的bis(imino) 二烯二离子,表明基于联体的降低和旋转状态的变化.
结论:
- 铁基复合物的电子结构可以通过减少和连接物修饰来调整.
- 结合体场强度和基结合体定位的变化导致铁中心的旋转状态发生变化.
- 这些发现为这些铁复合体的烯聚合催化机制提供了基本的见解.
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