5-Bromoisatin → 6-Bromo-3-methyl-2-[4-(trifluoromethyl)phenyl]-4-quinolinecarboxylic acid

Participants

Reaction Steps

A solution of potassium hydroxide (13.08 g, 233 mmol) in water (25.2 mL) was added slowly to a solution of 5-bromo-1H-indole-2,3-dione (9.76 g, 38.9 mmol) in ethanol (63.1 mL). 1-[4-(trifluoromethyl)phenyl]-1-propanone (8.64 g, 42.7 mmol) was added and the mixture was heated to reflux for 1 h. The reaction mixture was concentrated to remove the solvent, the residue was dissolved in water, and the mixture was washed three times with Et2O. The aqueous mixture was chilled, and concentrated HCl was added until the solution was pH 3. The solid was collected by filtration, washed with water, and dried under reduced pressure in a water bath at 100° C. The product was obtained as a light brown powder (15.6 g, 98%). This material was used without further purification. MS (m/z) 412.0 (M+H+).

Provenance & Evidence