从可隔离的同氧复合物中类似酶的C-H键的氧化
McKenna K Goetz1, Joseph E Schneider1, Alexander S Filatov1
1Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|December 2, 2021
概括
研究人员开发了一种新的氧复合物,可以有效地氧化形C-H键. 这一突破模仿了自然酶,并提供了对强大的合成氧化机制的见解.
科学领域:
- 无机化学 无机化学 有机化学
- 生物模拟化学 生物模拟化学
- 催化剂是一种催化剂.
背景情况:
- 性C-H键的选择性化是一种困难但有价值的化学转化.
- 大自然采用细胞P450酶,利用铁氧中间体进行有效的C-H键激活.
- 由酶启发的合成催化剂通常提出过渡金属-氧介质,但许多缺乏强大的C-H键的反应性.
研究的目的:
- 为了隔离和描述一个新的终端氧复合体.
- 为了研究过渡性氧中间体的C-H化活性.
- 阐明控制C-H激活和基化的机械因素.
主要方法:
- 一个新的终端Co(III) -oxo复合物的合成和表征,PhB(AdIm) 3Co(III) O.O.
- 通过氧化生成和研究一种过渡性Co(IV) -oxo中间体.
- 动力测量 (k1>130s-1在4°C) 和密度函数理论 (DFT) 分析.
主要成果:
- 隔离了PhB(AdIm) 3Co(III) O复合物的过程.
- 产生一种能够进行异形C-H氧化反应的活性Co(IV) -oxo物种.
- 演示一个 endergonic C-H 激活步骤,其次是一个 exergonic 基反弹步骤,驱动整体反应.
结论:
- 新的氧系统实现了与细胞染色体P450酶相比较的快速C-H氧化.
- 反应机制涉及初始的 endergonic C-H 激活和高度exergonic 激素反弹.
- 这种精确定义的系统为生物和合成基化过程提供了宝贵的见解.
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