Water co-catalysis in aerobic olefin epoxidation mediated by ruthenium oxo complexes
Water co-catalysis in aerobic olefin epoxidation mediated by ruthenium oxo complexes
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DOI：
10.1039/d3sc05516g
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发表时间：
2024-01-09
期刊：
影响因子：
8.4
通讯作者：
Hintermair，Ulrich
中科院分区：
文献类型：
--
作者：
Cao，Qun;Diefenbach，Martin;Hintermair，Ulrich
我们报告了一个多功能的钌卟啉催化剂系统，进行有氧环氧化的芳香族和脂肪族（内）烯烃在温和的条件下，产品收率高达95%，营业额（TON）高达300的发展。水被证明在反应中起着至关重要的作用，显着提高催化剂的效率和基板范围。采用计算研究和一系列实验技术的详细机理研究表明，水激活RuVI二氧代络合物通过氢键的烯烃环氧化，稳定RuIV单氧代中间体，并参与RuVI二氧代络合物的再生导致氧原子交换。在水的存在下，得到不同的动力学，并参与催化剂失活的副反应已被确定。
We report the development of a versatile Ru-porphyrin catalyst system which performs the aerobic epoxidation of aromatic and aliphatic (internal) alkenes under mild conditions, with product yields of up to 95% and turnover numbers (TON) up to 300. Water is shown to play a crucial role in the reaction, significantly increasing catalyst efficiency and substrate scope. Detailed mechanistic investigations employing both computational studies and a range of experimental techniques revealed that water activates the RuVI di-oxo complex for alkene epoxidation via hydrogen bonding, stabilises the RuIV mono-oxo intermediate, and is involved in the regeneration of the RuVI di-oxo complex leading to oxygen atom exchange. Distinct kinetics are obtained in the presence of water, and side reactions involved in catalyst deactivation have been identified.