Synthesis of indole-2-carbaldehydes, 2-(2-aminoethyl)- and 2-(2-aminopropyl)-indoles

Abstract

Various substituted 2-hydroxymethylindoles have been prepared by lithium aluminium hydride reduction of corresponding 2-ethoxycarbonylindoles and oxidised with activated manganese dioxide to the respective indole-2-carbaldehydes. Some of the aldehydes have been prepared from the 2-ethoxycarbonylindoles by the McFadyen and Stevens procedure and the two methods are compared. The aldehydes were condensed with nitromethane and nitroethane and the condensation products reduced with lithium aluminium hydride to obtain 2-(2-amino-ethyl)- and 2-(2-aminopropyl)-indoles.