Aerobic Oxidative Homo- and Cross-Coupling of Amines Catalyzed by Phenazine Radical Cations
作者:Rok Brišar、Felix Unglaube、Dirk Hollmann、Haijun Jiao、Esteban Mejía
DOI:10.1021/acs.joc.8b02345
日期:2018.11.2
Phenazine radical cations (PhRCs) were used for the first time as efficient metal-free catalysts for the oxidative homo- and cross-coupling of a variety of different amines. A series of functional PhRCs were prepared, characterized with X-ray diffraction, and their radical character was investigated with DFT calculations. They were tested as catalysts under neat conditions with low oxygen pressure
吩嗪自由基阳离子(PhRCs)首次作为有效的无金属催化剂用于多种不同胺类的氧化均相和交叉偶联。制备了一系列功能性PhRC,通过X射线衍射对其进行了表征,并通过DFT计算研究了它们的自由基特性。它们在低氧压力的纯净条件下作为催化剂进行测试,以高收率制备均相和交联的脂族和芳族亚胺。尽管所有合成的吩嗪均具有催化活性,但使用5,10-二氢-5,10-二甲基吩嗪自由基阳离子可获得最高的反应速率和最佳的选择性。通过荧光,紫外可见和EPR光谱,提出了PhRCs催化氧化胺偶联的机理。