一个单质Mn(IV) -oxo复合物的制备和特性
Trenton H Parsell1, Rachel K Behan, Michael T Green
1Department of Chemistry, University of Kansas, 2010 Malott Hall, 1251 Wescoe Hall Drive, Lawrence, Kansas 66045, USA.
Journal of the American Chemical Society
|July 6, 2006
概括
这项研究详细介绍了一种新型单核-氧复合物的合成和特征,特别是一个氧 (IV) 单元. 该研究突出了其独特的光谱特性和多样化的反应性,推动了催化研究.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 催化剂研究研究
背景情况:
- 氧复合物在生物和化学催化过程中至关重要.
- 具有终端氧联体的单体复合物,特别是氧 (IV) 复合物,很少见.
- 之前的研究重点是-III-O复合物,其中氧气裂变是关键步骤.
研究的目的:
- 为了合成和表征一种新型单核氧 manganese (IV) 复合体.
- 为了研究合成复合物的光谱和结构性质.
- 在各种化学转化中探索氧 (IV) 单元的反应性.
主要方法:
- 从一个Mn(III) -O前体中合成氧化 (IV) 复合物[MnIVH3buea (O) ]-
- 使用UV-Vis光谱,共振拉曼光谱和电子磁共振 (EPR) 进行了表征.
- 使用密度函数理论 (DFT) 支持结构赋值的计算分析.
主要成果:
- 成功制备和表征一个单核Mn(IV) -oxo复合体,S = 3/2基本状态.
- 谱学数据 (lambdamax = 635 nm, nu(Mn-O) = 737 cm-1) 和 EPR (g = 5.15, 2.44, 1.63) 证实了Mn(IV) -oxo的分配.
- DFT计算支持赋值,并表明Jahn-Teller扭曲,偏离三角形对称.
- 该复合物表现出多种反应性,包括O原子转移到素和与氨酸反应,但在DMSO中不稳定.
结论:
- 一个稳定的单核氧蒙 (((IV) 复合物已经合成并得到了充分的特征.
- 该综合体表现出独特的反应模式,展示了Mn(IV) -oxo单元在催化中的潜力.
- 这项工作扩展了已知的单核Mn(IV) -oxo复合体的例子及其化学行为.
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