Organoiodine Catalysed Intramolecular C−N bond Oxidative Coupling for the Synthesis of 3‐Monosubstituted Oxindoles

An efficient organoiodine‐catalysed intramolecular direct C–N bond oxidative coupling reaction is presented. Structurally diverse 3‐(mono)substituted oxindoles were rapidly obtained in a complex oxidative system in up to 87% yield. Various N‐alkoxy‐2‐phenylpropanamides were well‐tolerated. This study showed that the electronic effects on the aromatic ring of reactants have a crucial effect on the selectivity (C−N/C−O) of cyclisation products. In addition, gram‐scale synthesis and late‐stage modification of 3‐(mono)substituted oxindole derivatives revealed the practical application of this transformation.