N-Ethylaniline → Laquinimod

Participants

Reaction Conditions

Reaction Steps

N-Ethyl aniline (5.2 gm) was taken in methylene chloride (100 ml) and stirred for 10 minutes at 25-30° C. under nitrogen atmosphere. The resulting mass was followed by the addition of dichlorotriphenyl phosphorane (26.6 gm) at 25-30° C. and the reaction mixture was stirred for 15 minutes. 1,2-Dihydro-4-hydroxy-5-chloro-1-methyl-2-oxo-quinoline-3-carboxylic acid (10 gm) was added to the resulting mass at 25-30° C. followed by heating to reflux (40-45° C.) and then stirred for 3 hours at reflux. Methylene chloride was distilled out from the reaction mass under vacuum at below 45° C. The resulting residue was cooled to 25-30° C., followed by the addition of ethyl acetate (50 ml) and water (50 ml) at 25-30° C. and the resulting mixture was stirred for 30 minutes at 25-30° C. The separated solid was filtered, washed with water and then dried to yield 11.7 gm of laquinimod as a white colored solid (HPLC purity: 99.47%).

Provenance & Evidence