Controlled partial transfer hydrogenation of quinolines by cobalt-amido cooperative catalysis
Maofu Pang, Jiayi Chen, Shengjie Zhang, Rong‐Zhen Liao, Chen‐Ho Tung, Wenguang Wang
Abstract
Abstract Catalytic hydrogenation or transfer hydrogenation of quinolines was thought to be a direct strategy to access dihydroquinolines. However, the challenge is to control the chemoselectivity and regioselectivity. Here we report an efficient partial transfer hydrogenation system operated by a cobalt-amido cooperative catalyst, which converts quinolines to 1,2-dihydroquinolines by the reaction with H 3 N·BH 3 at room temperature. This methodology enables the large scale synthesis of many 1,2-dihydroquinolines with a broad range of functional groups. Mechanistic studies demonstrate that the reduction of quinoline is controlled precisely by cobalt-amido cooperation to operate dihydrogen transfer from H 3 N·BH 3 to the N=C bond of the substrates.