61500-87-6

2-Amino-4-trifluoromethylbenzoic Acid Methyl Ester is an intermediate used to prepare quinazolinedione sulfonamides as competitive AMPA receptor antagonists. It is also used in the synthesis of (arylamino)pyrimidobenzazepinones and pyrimidobenzazepinethiones as inhibitors of polo-like kinase 1 and potential antitumor agents.

Step 2; Preparation of methyl 2-amino-4-trifluoromethylbenzoate; Methyl 2-nitro-4-(trifluoromethyl)benzoate (106 g, 425 mmol) was dissolved in ethanol. To a slurry of 10% palladium carbon (11.0 g) in ethyl acetate (200 mL) was added ethyl acetate (2.2 L), and the suspension was stirred for 3 h at room temperature and 60 °C under a hydrogen atmosphere. Upon completion of the reaction, the suspension was filtered through a Celite pad and the pad was washed with additional ethyl acetate. The filtrate was concentrated under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography using isohexane/ethyl acetate (9:1) as eluent to afford methyl 2-amino-4-trifluoromethylbenzoate as a white crystalline solid (84 g, 95% yield).

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