PREPARATION OF ETHYLENE GLYCOL ADDUCTS AT 2,3-POSITIONS OF INDOLES WITH HYPERVALENT IODINE

摘要

An efficient method for protection-deprotection of the 2,3-bond of indoles was developed.Treatment of various indole derivatives with hypervalent iodine-ethylene glycol in the presence of ammonium chloride provided 2,3-ethylene glycol bridged adducts in excellent yields.The adducts,which possessed a masked form of pyrrole moiety in the indole nucleus,could be converted back to the mother indoles under mild reductive conditions.