Iodine‐Catalyzed Oxidation of N‐Substituted Indoles by Using Chloramine‐B: A Facile and Practical Approach to Isatins.

An efficient method for the iodine-catalyzed oxidation of N-substituted indoles by using chloramine-B under mild reaction conditions was explored. This reaction was found to be tolerant to a variety of functional groups and provided the corresponding isatins in moderate to excellent yields. In addition, application of this method to the one-pot synthesis of 3-hydroxyoxindole and N-methylisatin oxime was realized.