2-Oxobutanoic Acid → 6-Fluoro-3-methyl-7-(methyloxy)-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylic acid

Participants

Reaction Steps

To a solution of 4-fluoro-3-(methyloxy)aniline (25.0 g, 177 mmol) in ethanol (300 mL) was added 3-(trifluoromethyl)benzaldehyde (30.8 g, 177 mmol) dropwise. The mixture was stirred at reflux for 1 h, and 2-oxobutanoic acid (18.08 g, 177 mmol) was added portionwise. The reaction mixture was stirred at reflux for an additional 3 h, cooled to room temperature, and stirred overnight. The solid precipitate was collected by filtration, washed with ethanol, and air dried to give 6-fluoro-3-methyl-7-(methyloxy)-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylic acid (29.1 g, 43% yield). 1H NMR (400 MHz, DMSO-d6) δ14.34 (br. s., 1H), 7.94-7.98 (m, 2H), 7.88 (d, J=7.78 Hz, 1H), 7.77 (t, J=7.65 Hz, 1H), 7.71 (d, J=8.53 Hz, 1H), 7.54 (d, J=12.05 Hz, 1H), 4.03 (s, 3H), 2.38 (s, 3H); MS (m/z) 380.1 (M+H+).

Provenance & Evidence