Effect of reaction conditions on the Claisen-Schmidt synthesis of selected 1,3-diphenylprop-2-en-1-one derivatives

Abstract

This research aimed to investigate the Claisen-Schmidt condensation reaction for the wet synthesis of chalcones and suggest the ideal reaction conditions for the process. Three chalcones, namely 1,3-diphenylprop-2-en-1-one, 1-(4-nitrophenyl)-3-phenylprop-2-en-1-one and 3-(2,4,6-trimethoxyphenyl)-1-phenylprop-2-en-1-one, were synthesized under varying conditions while closely monitoring the effects on product yield and quality. The temperature was varied between room and ice bath (<10ºC) conditions. Cold aqueous NaOH and KOH were varied as catalysts while absolute ethanol or methanol was used as the solvent in each scenario. Thin layer chromatography (TLC) was employed to monitor the progress of the reaction. The open capillary method was used to determine the melting point of the products and the values obtained were uncorrected. The results obtained showed that a combination of methanol as a solvent and NaOH as a catalyst, under ice-cold condition, was optimum for the wet synthesis of the chalcones. This combination gave the highest yield (98.26%) and purity of products.