AN EFFICIENT ONE-POT SYNTHESIS OF INDOLYL-4<i>H</i>-CHROMENE DERIVATIVES

Abstract

A new one-pot three-component reaction for the synthesis of indolyl-4H-chromene derivatives has been developed. The synthesis was achieved by reacting salicylaldehydes, (E)-N-methyl-1-(methylsulfanyl)-2-nitroethenamine, and indoles in the absence of solvent using triethylamine as a catalyst. The final products were isolated by precipitation after the addition of ethanol to the reaction mixture. This transformation involves the formation of indole-substituted chromene ring by creation of two C–C bonds and one C–O bond in a single synthetic operation. This rapid one-pot reaction does not require chromatographic purification and provides the indolyl-4H-chromene derivatives in good yields.