质子促进的氧原子转移与非黑米铁的质子合电子转移 (IV) -oxo复合体
Jiyun Park1, Yuma Morimoto, Yong-Min Lee
1Department of Bioinspired Science, Ewha Womans University, Seoul 120-750, Korea.
Journal of the American Chemical Society
|February 21, 2012
概括
甲酸显著增强非血红素铁 (IV) -oxo复合物的硫化作用. 这种由酸促进的硫酸化是通过直接的氧原子转移发生的,而不是由质子合的电子转移,揭示了不同的反应机制.
科学领域:
- 无机化学 无机化学 有机化学
- 反应机制 反应机制
- 催化剂是一种催化剂.
背景情况:
- 在氧化催化过程中,非血红铁 (IV) - 氧合物复合物至关重要.
- 了解酸性添加剂在调节反应性的作用至关重要.
- 硫氧化安醇是有机合成中的一个关键转化.
研究的目的:
- 为了研究酸对非血红铁 (IV) - 氧复合物的硫化硫化的作用.
- 阐明反应机制,区分氧原子转移和质子合电子转移 (PCET).
- 为了确定铁复合体的还原潜力,并分析电子转移的动力学.
主要方法:
- 在不同酸度下监测反应速度的动力学研究.
- 减少潜力的光谱测定.
- 马库斯理论的应用,以分析电子转移过程.
主要成果:
- 甲酸 (70% HClO(4)) 显著提高了 thioanisoles 的硫化率,由 [(N4Py) Fe ((IV) ((O) ](2+) 复合体.
- 从还原剂到铁复合物的质子合电子转移 (PCET) 显示了对酸度的二次依赖,表明了两质子参与.
- [{N4Py) Fe{IV) }{O) }{2+) 的降解潜力被确定为1.43V与SCE相比.
- 酸促硫氧化通过一阶段的氧原子转移机制进行,与PCET不同.
结论:
- 甲酸作为[{N4Py) Fe{{IV}{O}}}2+的硫化促进剂,有利于直接的氧原子转移途径.
- 硫氧化反应的反应机制与观察到电子转移到铁复合体的PCET机制不同.
- 这项研究提供了关于高价值铁复合物的酸促反应的机制差异的见解.
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