在LFeIIIOIPh的反应性上的赤道同质体的影响
Dóra Lakk-Bogáth1, Dénes Pintarics1, Patrik Török1
1Research Group of Bioorganic and Biocoordination Chemistry, University of Pannonia, H-8201 Veszprém, Hungary.
Molecules (Basel, Switzerland)
|January 11, 2024
概括
这项研究表明,皮里丁协同连接体如何影响氧化反应中的铁(III) - 二基反应性. 不同的辅配体改变铁中间体.
科学领域:
- 生物有机化学 生物有机化学
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
背景情况:
- 已知赤道配体会影响生物系统中氧铁中间体的氧化还原潜力和稳定性.
- 没有先前的研究已经调查了对铁的co-ligands的影响(III) -iodosylbenzene (FeIII-IOPh) 物种.
- 了解这些影响对于设计高效的氧化催化剂至关重要.
研究的目的:
- 为了研究替代的皮里丁协同连接体对铁 (III) - 酸添加物的反应性的影响.
- 探索这些辅配体在硫化和环氧化反应中的作用.
- 为了阐明氧原子从铁中间体转移 (OAT) 的机制.
主要方法:
- 在氧化反应中使用了 [FeII(PBI) ]3](OTf) 2 和 PhI(OAc) 2 的催化量.
- 采用替代的皮里丁辅配体 (4R-Py) 来调节反应性.
- 进行了机理学研究,包括竞争实验和线性自由能量关系 (LFER).
- 进行紫外线可见光谱测试以表征中间体并监测颜色变化.
主要成果:
- 选择性氧化安醇,cis-cyclooctene,和 stilbenes 取得良好的优异的产量.
- 联体选择显著影响FeIII-IOPh中间体的反应性和选择性.
- 有证据表明,反应性物种具有电友性,这得到了LFER分析的支持.
- 紫外线可见的数据证实了[(PBI) 2 (((4R-Py) FeIII-IOPh]3+中间体和协联体效应的存在.
结论:
- 替代的皮里丁协同连接物有效调整氧化催化过程中铁(III) - 酸添加物的反应性.
- 该研究提供了对这些铁复合体介导的氧原子转移反应的机械洞察.
- 这些发现凸显了合理设计的铁复合体在选择性氧化过程中的潜力.
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