A Facile synthesis of Novel Indole-Based Chalcones (E)-1-(2-Chloro-1-Methyl-1H-Indol-3-Yl)-3-Arylprop-2-En-1-Ones

Abstract

A facile and general synthesis of 23 novel indole-based chalcones, ( E)-1-(2-chloro-1-methyl-1 H-indol-3-yl)-3-arylprop-2-en-1-ones, has been achieved in good yields of 71–89% by the Claisen–Schmidt condensation reaction of 3-acetyl-2-chloro- N-methylindole with variously substituted araldehydes using 1,4-dioxane as solvent in the presence of 5% aq. KOH. A similar reaction using furan-2- or thiophene-2-carbaldehyde gave analogous products in good yield, but an unexpected aldol reaction occurred with 2-nitrobenzaldehyde and the stable aldol product was isolated as the major product in a good yield of 73%.