Water → 4-(2-Acetylamino-6-phenoxy-quinolin-3-yl)-4-(tetrahydro-pyran-4-yl)-butyric acid

Participants

Reaction Steps

To a stirred solution of the solid isolated in Step E (6.49 g, 15.1 mmol), tetrabutylammonium bromide (0.078 g, 0.24 mmol), acetic acid (16 mL) in a mixture of benzene (140 mL) and water (140 mL) at 0° C., potassium permanganate (8.34 g, 52.8 mmol) was added slowly. The reaction mixture was then stirred at room temperature for two hours. Sodium bisulfite was added portion wise slowly into the reaction mixture until the color disappeared. The reaction mixture was made basic by adding sodium hydroxide solution (1.0 N). The resulting solution was extracted with diethyl ether twice. The aqueous phase was made acidic (pH 2) by adding hydrochloric acid (3 N). The resulting solution was extracted with chloroform three times. The combined chloroform extracts were washed with brine and dried over magnesium sulfate. The solution was filtered and concentrated to yield 4-(2-acetylamino-6-phenoxy-quinolin-3-yl)-4-(tetrahydro-pyran-4-yl)-butyric acid as a yellow solid.

Provenance & Evidence