二次协调球对非黑米铁复合物的活性的影响:一个实验和DFT方法
Sumit Sahu1, Leland R Widger, Matthew G Quesne
1Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Journal of the American Chemical Society
|July 10, 2013
概括
新的铁复合体与生物模拟性连接体表明,连接体结构控制反应性. 控制的替代剂能够快速化,而胺基团稳定中间体,防止这种反应.
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:
- 非海姆铁酶在生物氧化反应中起着至关重要的作用.
- 了解这些酶的机制是开发合成催化剂的关键.
- 连接物设计显著影响铁复合物的反应性和稳定性.
研究的目的:
- 为了合成和表征新的生物仿真铁复合体与量身定制的连接体环境.
- 为了研究连接物替代剂对铁中心的自旋状态和反应性的影响.
- 探索二次协调球相互作用在催化氧化反应中的作用.
主要方法:
- 合成新的N4Py (二) 和N4Py (二,胺) 连接体.
- 铁 (II) 复合物的形成和特征.
- 谱学和结构分析以确定协调环境和电子特性.
- 机械学研究探测反应途径,包括旋转状态变化和中间体形成.
主要成果:
- 两个新的铁 (II) 复合物[Fe (II) N4Py (II) 2Ph (II)) NCCH (III) BF (IV) ]2和[Fe (II) N4Py (II) 2Ph,胺 (II) ]BF (IV) ]2已成功合成.
- 在第一个复合体中控制的替代剂定向促进了Fe(IV) ((O) 中间体的三重旋转反应,从而导致高效的基化.
- 在铁中心附近加入一个胺基稳定了高旋转的Fe(III) OOR物种,这并没有导致烯氧化.
结论:
- 二次协调球相互作用,例如基组与基团的结,对非海姆铁中心的反应性有深远的影响.
- 连接体设计对于控制旋转状态转换和指导氧化反应的结果至关重要.
- 这些发现为开发选择性和高效的仿生催化剂提供了宝贵的见解.
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