一个更具反应性的三角形-双形高旋转氧铁 (IV) 复合体,具有 cis-labile 位点
Jason England1, Yisong Guo, Katherine M Van Heuvelen
1Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|July 12, 2011
概括
研究人员合成了一种新的高旋转氧铁 (IV) 复合体,[Fe (IV) ] (O) [TMG (II) ] (dien) [CH (III) ] (CN) ] (二+). 与类似化合物相比,这种复合物及其衍生物显示了基质氧化率的提高.
科学领域:
- 无机化学 无机化学 有机化学
- 有机金属化学 有机金属化学
- 生物有机化学 生物有机化学
背景情况:
- 高旋转氧铁 (IV) 复合物是各种氧化反应中的关键中间体.
- 了解这些复合物的结构-活性关系是开发高效催化剂的关键.
- 之前的研究已经探讨了相关的复合物,如[Fe ((IV) ((O) ((TMG ((3) )))) ((2+).
研究的目的:
- 为了合成和表征一种新的三角形-双形高旋氧铁 (IV) 复合体.
- 研究连接体替代对氧铁 (IV) 复合物的特性和反应性的影响.
- 将新复合体的催化活性与现有的催化活性进行比较.
主要方法:
- 合成氧铁 (IV) 复合物 (Fe (IV) (O) (TMG (2) (dien)) (CH (3) (CN)) (二+) 的合成.
- 合成复合物的光谱表征.
- 与亚化物 (N(3)(-)) 和化物 (Cl(-)) 离子进行替代反应,形成新的复合物.
- 对分子间基质氧化率的评估.
主要成果:
- 三角双金字塔高旋转 (S = 2) 氧铁 (IV) 复合物[Fe (IV) (O) (TMG (II) (dien) (CH (III)) (CN) ()) 2+) ]已成功合成和表征.
- 新的氧铁 (IV) 复合物[Fe (IV) (O) (TMG (2)) (X) (X=N (III) (--) 和Cl (--)) 通过配体替代得到.
- 合成的复合物表现出与[Fe(IV) ((O) ((TMG ((3) ) ] ((2+) 相比,分子间基质氧化率更高,这归因于降低的硬质体积.
结论:
- 新型氧铁 (IV) 复合体对氧化反应表现出有前途的催化活性.
- 干体设计在调节高旋转氧铁 (IV) 复合物的反应性方面发挥着重要作用.
- 这项研究提供了对开发更高效的基于铁的氧化催化剂的见解.
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