N-Ethylaniline → Laquinimod

Beteiligte Stoffe

Reaktionsschritte

Laquinimod acid was prepared according to the method described in U.S. Pat. No. 6,875,869: 5-Chloro-1,2-dihydro-4-hydroxy-1-methyl-2-oxo-quinoline-3-carboxylic acid methyl ester (3.0 g), N-ethylaniline (2 eq 2-2.88 ml), and heptane (60 ml) were heated and the volatiles, mainly heptane and formed methanol, (32 ml) distilled off during 6 hours and 35 minutes. After cooling to room temperature the crystalline suspension was filtered and the crystals were washed with heptane and dried in vacuum to yield laquinimod acid (3.94 g, 98%) as white to off-white crystals.

Herkunft & Nachweise