4-(Trifluoromethyl)aniline → Leflunomide

Participants

Reaction Steps

A solution of 0.05 mol of 5-methylisoxazole-4-carbonyl chloride (7.3 g) in 20 ml of acetonitrile is added dropwise at room temperature to a solution of 0.1 mol of 4-trifluoromethylaniline (16.1 g) in 150 ml of acetonitrile. After stirring for 20 minutes, the precipitated 4-trifluoromethylaniline hydrochloride is filtered off with suction and washed twice with 20 ml of acetonitrile each time and the combined filtrates are concentrated under reduced pressure. 12.8 g of white crystalline 5-methylisoxazole-4-carboxylic acid (4-trifluoromethyl)-anilide (compound 1) are thus obtained.

Provenance & Evidence