在铜光氧催化原子转移激素添加中研究竞争的内部和外部球电子转移途径:结束循环
Le Nhan Pham1, Angus Olding2, Curtis C Ho2
1Institute for Nanoscale Science and Technology, Flinders University, South Australia, Australia.
Angewandte Chemie (International ed. in English)
|September 24, 2024
概括
这项研究表明,铜催化剂通过内部球电子转移 (ISET) 启动原子转移激素添加. 催化剂再生,对于反应完成和酶选择性至关重要,也通过ISET在基态中发生.
科学领域:
- 有机金属化学 有机金属化学
- 光催化作用的光催化
- 激进反应是一种激进的反应.
背景情况:
- 像[Cu(dap) ]2+这样的铜复合体介于原子转移激素添加 (ATRA).
- 了解电子转移机制 (ISET与OSET) 是控制反应结果的关键.
- 在ATRA反应中的产品比率可以根据基质和条件显著变化.
研究的目的:
- 调查内部球电子转移 (ISET) 和外部球电子转移 (OSET) 在[Cu(dap) ]2+催化ATRA反应中的作用.
- 为了使实验观测与拟议的电子转移机制相协调.
- 开发一个全面的框架,以了解铜光催化ATRA中的催化剂再生和酶选择性.
主要方法:
- 综合计算和实验方法.
- 利用五种不同的基来探索反应结果.
- 分析的产品分布 (R-SO2Cl与R-Cl) 和反应动力学.
主要成果:
- 光激发的[Cu(dap) 2+启动了通过ISET的光电子转移.
- 基态催化剂再生主要通过ISET发生.
- 产品比率是由直接催化剂再生和连接物交换的竞争速率决定的.
结论:
- 该研究确定ISET是ATRA系统中启动和再生的主要机制.
- 一个精细的概念模型澄清了催化循环和影响产品选择性的因素.
- 通过ISET进行基态催化剂再生被确定为奇拉铜催化ATRA中异能选择性的关键决定因素.
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