In the Conrad-Limpach synthesis, quinolones are obtained by reacting aniline with 3-ketoesters. Under kinetic conditions the 4-quinolone is obtained and under thermodynamic conditions the 2-quinolone.

conrad limpach knorr 01


conrad limpach knorr 02

By means of an analogous mechanism, but carrying out the first stage at 140ºC, the thermodynamic product is obtained