Decarboxylative Synthesis of Functionalized Oxindoles via An Iron‐Initiated Radical Chain Process and Application in Constructing Diverse Fused‐Indoline Heterocycles

Rapid construction of diverse fused‐indoline−heterocycle (FIH) frameworks including high‐value pyrroloindolines, furoindolines and thienoindolines in a two‐step sequence has been described. The key to success hinges on the adoption of peresters as α‐heteroatom alkyl radical precusors, which can smoothly react with N ‐arylacrylamides via a radical chain process initiated by inexpensive FeCl 2 ⋅4H 2 O to afford the functionalized oxindoles, the key intermediates to FIH skeletons. The approach features operationally‐simplicity, broad substrates scope and mild conditions.