Transition Metal‐Controlled Direct Regioselective Intermolecular Amidation of C−H Bonds with Azodicarboxylates: Scope, Mechanistic Studies, and Applications
作者:He‐Yuan Bai、Xin Fu、Jin‐Long Pan、Hai‐Qian Ma、Zhi‐Min Chen、Tong‐Mei Ding、Shu‐Yu Zhang
DOI:10.1002/adsc.201800623
日期:2018.11.5
A simple and efficient transition metal‐catalyzed C−H amidation with azodicarboxylates has been developed. Under silver catalysis, the amide substrates undergo regioselective C−H amidation at C5‐position of the quinoline. Conversely, with palladium as the catalyst, the reaction gave β‐C(sp3)−H amidation products via the activation of methylene C(sp3)−H bonds. Mechanistic studies suggested that the
已开发出一种简单有效的过渡金属催化的偶氮二羧酸酯化CH酰胺化反应。在银催化下,酰胺底物在喹啉的C5位发生区域选择性的CH酰胺化。相反,以钯为催化剂,反应通过亚甲基C(sp 3)-H键的活化得到β-C(sp 3)-H酰胺化产物。机理研究表明,单电子转移和有机金属机理途径引起了这些令人惊讶的和截然不同的结果。基于机理分析,我们设计了钯催化/银促进的直接分子间β-C(sp 3)-H酰胺化反应以活化亚甲基C(sp 3)5-氯-8-氨基喹啉(CQ)保护的脂族酰胺与偶氮二羧酸酯的-H键。两种催化方案均提供了替代,便捷和简单的策略,以区域选择性方式有效地访问结构独特的含C N键的化合物。