Assembly of 3-acyloxindoles via CuI/L-proline-catalyzed intramolecular arylation of β-keto amides

Intramolecular coupling of beta-keto 2-iodoanilides catalyzed by CuI/L-proline in DMSO occurs at room temperature, affording substituted 3-acyloxindoles in good yield. Electronic effects on the aromatic ring have little influence on this reaction. Variations at the 1, 3, 4, 5, and 6 positions of the oxindoles were achieved by employing the corresponding amides.