Environmentally Friendly Protocol for 2,3-Difunctionlization of Indole Derivatives
Environmentally friendly and highly regioselective C-3 dichlorination and C-2 oxidation of N-substituted indoles have been established using NaCl as a chlorine source and H2O as an oxygen source. A series of 3,3-dichloro-2-oxindoles were obtained in moderate to excellent yields. The gram-scale synthesis and derivatization reaction were explored. The possible mechanism for this reaction was elucidated.
Sun, Wen-Wu,Chen, Na,Wei, Ting-Ting,You, Guo-Jing,Yang, Hao,Liu, Ji-Kai,Wu, Bin
Synthesis of 3,3-Dihalo-2-oxindoles from 2-Substituted Indoles via Halogenation–Decarboxylation/Desulfonamidation–Oxidation Process
A novel one-pot reaction which combines halogenation, decarboxylation/desulfonamidation with oxidation has been developed. Diverse valuable 3,3-dihalo-2-oxindole compounds can be produced rapidly and safely with isolated yields of up to 98% under mild conditions. (Figure presented.).