铁的N-O键同解 (II) TEMPO复合物产生一种铁 (III) 氧中间体
Jeremy M Smith1, Derick E Mayberry, Charles G Margarit
1Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces New Mexico 88003, USA. jesmith@nmsu.edu
Journal of the American Chemical Society
|March 29, 2012
概括
研究人员将TEMPO与铁 (I) 复合物发生反应,形成稳定的铁 (II) 氧化物复合物. 这种复合物经过热解,产生活性铁 (III) 氧介质,用于氧原子转移反应.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 反应机制 反应机制
背景情况:
- 稳定的铁复合体对于催化是至关重要的.
- 了解铁在不同氧化状态中的反应性是关键.
- (2,2,6,6-tetramethylpiperidin-1-yl) oxyl 是一种稳定的基因,用于各种化学转化.
研究的目的:
- 为了合成和描述一个新的铁(I) -TEMPO adduct.
- 为了研究铁-TEMPO复合物的反应和分解途径.
- 探索铁氧介质在氧原子转移反应中的潜力.
主要方法:
- 铁的合成 (I) 前体PhB (MesIm) (Fe) (COE) 的合成.
- 铁 (I) 复合物的反应与TEMPO.
- 使用X射线晶体学和光谱学进行结构性表征 (NMR,EPR,Mössbauer).
- 热解研究诱导N-O键同解.
- 用三甲基基的捕捉实验.
主要成果:
- 形成 κ(1) -TEMPO 复合物 PhB ((MesIm) ((3) Fe ((TEMPO) 与双价铁结合一个氧化离子.
- 该复合物是对一种铁 (II) 过氧物种的异电子.
- 热解产生了一种铁 (III) 氧中间体.
- 铁 (III) 氧介质在氧原子转移中表现出活性.
- 氧介质被捕获,形成一个铁(II) 酒精复合物PhB(MesIm) ((3) Fe(OCPh ((3)).
结论:
- 一种新的铁氧化物复合物已成功合成和表征.
- 铁 (II) 复合物的 N-O 键同解产生一种活性铁 (III) 氧物种.
- 这种铁 (III) 氧介质能够转移氧原子,突出其催化潜力.
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