Hydrogen Peroxide Promoted Metal-Free Oxidation/Cyclization of α-Hydroxy N-Arylamides: A Facile One-Pot Synthesis of Isatins

A novel, efficient, and environmentally friendly method was developed for converting -hydroxy N-arylamides into isatins (1H-indole-2,3-diones) by using hydrogen peroxide as oxidant. The reactions proceeded smoothly under metal-free conditions and generated the corresponding products in good to excellent yields. This method has advantages of a broad substrate scope and simple operations.