The preparation of substituted quinoline derivatives through a Friedlander condensation reaction utilizing the ionic liquid [bmim][BF4] as the reaction medium and iron chloride hexahydrate (FeCl3·6H2O) as a catalyst is described. The advantages in using this method include its environmental friendliness, simple operating process in both mild and neutral reaction conditions, and good yields.Key words: ionic liquid, Friedlander reaction, quinoline derivatives, green chemistry.
The remarkable feature of this work was using green, non-toxic PEG-400 as a carbon synthon for highly selective synthesis of quinolines (quinoxalines) and methylquinolines (methylquinoxalines) under metal-free conditions.