Oxidant effect of H2O2 for the syntheses of quinoline derivatives via one-pot reaction of aniline and aldehyde

Article abstract of DOI:10.1080/00397911.2011.563022

(Chemical Equation Presented) A convenient one-pot method for the synthesis of substituted quinolines via the reaction of aniline and aldehyde in the presence of a Lewis acid (AlCl₃) and an oxidant (H₂O ₂) has been developed. Hydrogen peroxide was found to promote the reaction by its function as a hydrogen hunter, hindering the formation of by-product N-alkylaniline. The effect of the oxidant on the yield and selectivity was studied. When the molar ratio of aniline, n-butyraldehyde, and H₂O₂ was 1:3:0.5 at 25°C, the yield of 3-ethyl-2-propylquinoline was improved from 64% (reaction without H ₂O₂) to 84% (with H₂O₂), and the quinoline selectivity was improved to almost 100%. Moreover, the reaction time was obviously reduced. The substituent effect was also investigated in this work. Copyright Taylor & Francis Group, LLC.