Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University, Shenzhen Graduate School , Shenzhen 518055, China.
J Am Chem Soc. 2018 Jan 17;140(2):735-740. doi: 10.1021/jacs.7b11351. Epub 2018 Jan 8.
Direct aerobic α,β-dehydrogenation of γ,δ-unsaturated amides and acids using a simple iridium/copper relay catalysis system is described. We developed a new strategy that overcomes the challenging issue associated with the low α-acidity of amides and acids. Instead of α-C-H metalation, this reaction proceeds by β-C-H activation, which results in enhanced α-acidity. Conjugated dienamides and dienoic acids were synthesized in excellent yield with this reaction, which uses a simple reaction protocol. Mechanistic experiments suggest a catalyst resting state mechanism in which both α-C-H and β-C-H cleavage is accelerated.
本文描述了使用简单的铱/铜接力催化体系对γ,δ-不饱和酰胺和酸进行直接有氧α,β-脱氢反应。我们开发了一种新策略,克服了酰胺和酸的低α酸性相关的难题。与α-C-H 金属化相反,该反应通过β-C-H 活化进行,从而增强了α-酸性。该反应使用简单的反应方案,以优异的收率合成了共轭二烯酰胺和二烯酸。机理实验表明,催化剂的休眠态机制中同时加速了α-C-H 和β-C-H 的断裂。