高价值的非海姆铁. 高价值的非海姆铁. 两种不同的铁 (IV) 种源于一种常见的铁 (II) 前体
Michael P Jensen1, Miquel Costas, Raymond Y N Ho
1Department of Chemistry and the Center for Metals in Biocatalysis, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|July 28, 2005
概括
铁 (II) 复合物与三丁氧化反应,形成新的铁 (IV) 物种. 这项研究揭示了前所未有的甲铁 (IV) 复合物和富含铁 (IV) 的化学反应,这些化学反应得到了BPMCN连接体的支持.
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:
- 铁复合物是各种化学转换中的关键催化剂.
- 了解铁复合物与氧化剂的反应性是开发新催化系统的关键.
- BPMCN联体为稳定反应性铁物种提供独特的协调特性.
研究的目的:
- 为了研究一种特定的铁 (II) 复合物与三-丁氧化的反应.
- 描述由此产生的铁中间体和产品,特别关注铁 (IV) 种.
- 探索溶剂和温度对反应路径和铁物种化的影响.
主要方法:
- 铁 (II) 前体复合物[Fe (II) ] (β-BPMCN) (OTf) ]的合成和表征.
- 在不同温度和溶剂条件下 (CH2Cl2,CH3CN) 与三丁氧化 (tBuOOH) 反应.
- 光谱和分析技术包括UV-Vis,Mössbauer光谱,EXAFS,共振拉曼,NMR和质谱用于中间物和产品的识别.
主要成果:
- 在两种溶剂中形成甲基氧铁 (III) 中间体 (2).
- 在更高的温度下 (90%的产量) 将2-NCMe转化为铁(IV) -oxo物种 (3) 在亚丁中.
- 在低温下在二甲中生成一个前所未有的甲铁 (IV) 复合物 (4),其特点是多种光谱方法.
结论:
- BPMCN配体有效地支持各种铁的化学作用,包括形成一种新的甲铁的复合物.
- 反应条件 (溶剂,温度) 显著影响铁中间体的物种化和反应性.
- 这项工作扩大了对非血红素铁化学及其在氧化催化中的潜力的理解.
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