Cu-Catalyzed Coupling of <i>O</i>
-Acyl Oximes with Isatins: Domino Rearrangement Strategy for Direct Access to Quinoline-4-Carboxamides by C-N Bond Cleavage
A mild domino rearrangement strategy for the direct access to substituted quinoline‐4‐carboxamides has been developed. This copper‐catalyzed coupling reaction of O‐acyl oximes with isatins in the presence of molecular oxygen as the sole oxidizing agent proceeds through a ring expansion of the isatins through cleavage of the two CN bonds
An efficient and alternative isatin‐to‐quinoline strategy illustrates the metal‐like behavior of molecular iodine in the N−O reduction of ketoxime acetates. This process involves N−O/C−N bond cleavages and C−C/C−N bond formation to furnish pharmacologically significant quinoline‐4‐carboxamide derivatives. In this process, metal catalysts and extra oxidants are unnecessary. Mechanistic studies confirm
一种有效的替代品,从靛红到喹啉的策略说明了在碘化乙酸酮肟的N-O还原中分子碘的金属样行为。此过程涉及N / O / C-N键断裂和C-C / C-N键形成,以提供具有药理学意义的喹啉-4-羧酰胺衍生物。在此过程中,不需要金属催化剂和额外的氧化剂。机理研究证实了分子碘在亚氨基自由基生成过程中的关键作用,因为分子碘可以类似于过渡金属的方式催化单电子还原偶联反应。
A simple and directsynthesis of substituted2-phenylquinoline-4-carboxamidesfrom 3-substituted-3hydroxyindolines in presence of ammonium acetate is described. The developed protocol also allows synthesis of the carboxamide moeity directly from isatin and acetophenone in one pot under optimized conditions. The protocol has the merits of simple reaction conditions, easy work up process and good yields