Copper(I)-Catalyzed Radical Carbamylation/Cyclization of 2-Aryl--methacryloylindoles with Substituted Formamides to Assemble Amidated Indolo[2,1-]isoquinolin-6(5)-ones.

An efficient synthesis of amidated indolo[2,1-]isoquinolin-6(5)-ones has been achieved via copper(I)-catalyzed radical carbamylation/cyclization of 2-aryl--methacryloylindoles with substituted formamides. In this reaction, an isoquinoline ring was constructed by carbamylation of a carbon-carbon double bond in 2-arylindoles. This strategy successfully introduces the substituted amide group into the indolo[2,1-]isoquinoline skeleton and has advantages such as wide substituent scope, mild reaction conditions, high regioselectivity, and good to excellent yields.