Copper-Catalyzed [3 + 2] Annulation of O-Acyl Oximes with p-Hydroquinones for the Synthesis of 5-Hydroxyindoles

Abstract

A copper-catalyzed [3 + 2] annulation of O-acyl oximes with 2-electron-withdrawing group substituted p-hydroquinones for the efficient synthesis of polysubstituted 5-hydroxyindoles is developed. Further intramolecular cyclization leads to the concise and rapid construction of several kinds of 3,4-and 4,5-fused polycyclic indoles.