反应详情

Benzyl 4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylate (Example 66a) (0.6 g, 2.04 mmol) was dissolved in DMF (8 mL) and heated at 70° C. under a hydrogen balloon in the presence of 10% Pd/C (0.15 g) for 1 hour. The Pd/C was filtered out and washed with dichloromethane and the solvents were removed under vacuum. The residue was dissolved/suspended in NaOH (2M, 40 mL), stirred at room temperature for 30 minutes and the solution washed with dichloromethane. The aqueous layer was cooled to 0° C. and acidified to pH 1 with 2M HCl. The resultant precipitate was collected and washed with dichloromethane to give 4-amino-2-oxo-1,2-dihydroquinoline-3-carboxylic acid (0.050 g, 12%) as a light yellow solid. M.p.: >250° C. 1H NMR (400 MHz, DMSO-d6) δ 7.32 (m, 1H), 7.39 (d, J=7.6 Hz, 1H), 7.69 (m, 1H), 8.27 (d, J=8.4 Hz, 1H), 8.86 (s, 1H), 9.87 (s, 1H), 11.95 (s, 1H). MS 205 (MH+).

1. filtrationThe Pd/C was filtered out
2. washwashed with dichloromethane
3. customthe solvents were removed under vacuum
4. washthe solution washed with dichloromethane
5. temperatureThe aqueous layer was cooled to 0° C.
6. customThe resultant precipitate was collected
7. washwashed with dichloromethane