Copper/Nafion‐Catalyzed Hydroarylation Process Involving Ketenimine Intermediates: A Novel and Synthetic Approach to 4‐Sulfonamidoquinoline‐2‐ones and Derivatives Thereof

Abstract A copper(II)/NafionNR50‐catalyzed cascade is demonstrated, wherein in situ keteneimine formation and hydroarylation processes are involved. Various substituted 4‐sulfonamidoquinolin‐2‐ones and various derivatives thereof were obtained. The robust toluenesulfonamide protecting group can be removed on demand in a mild light‐promoted process to provide access to otherwise difficult to obtain 4‐aminoquinolin‐2‐ones. magnified image