Hydrochloric Acid → 4-(3,5-dichloropyridin-4-ylamino)-8-hydroxy-7-methoxyquinolin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

A solution of 8-(cyclopropylmethoxy)-4-(3,5-dichloropyridin-4-ylamino)-7-methoxyquinolin-2(1H)-one (99%. 23.8 g, 57.9 mmol) and conc. HCl (150 mL) was warmed at 40° C. for 30 min and then water (0° C., 150 mL) was added. The resulting mixture was stirred vigorously at 0° C. for 1 h, filtered, and then washed with water (0° C., 100 mL). A mixture of the resulting solid and 0.5 M pH 7 phosphate buffer (300 mL) was stirred vigorously at 0° C. for 30 min, filtered, washed with water (0° C., 300 mL), and then dried in an oven to give 19.9 g of 4-(3,5-dichloropyridin-4-ylamino)-8-hydroxy-7-methoxyquinolin-2(1H)-one as a yellow solid. 1H NMR (400 MHz, DMSO-d6): δ 9.69 (s, 1H), 9.51 (s, 1H), 8.78 (s, 3H), 7.65 (d, 1H), 7.01 (d, 1H), 3.90 (s, 3H); MS (ESI): 352.2.

Provenance & Evidence