8-Chloro-4-oxo-1,4-dihydro-2,5-quinolinedicarboxylic acid → 4-Oxo-1,4-dihydro-2,5-quinolinedicarboxylic acid

Participants

Reaction Steps

To a solution of 25 (7.90 g, 29.5 mmol) in 10% aqueous KOH solution (100 mL) was added 10% Pd/C (0.500 g). The reaction mixture was hydrogenated (50 psi) on a Parr hydrogenation apparatus at room temperature for 4 h. The catalyst was filtered off on a pad of celite and the filtrate was acidified with 2N HCl to pH=6.5, where a solid precipitated and was collected through a filtration. The solid was washed with H2O (100 mL) and Et2O (100 mL), and dried in vacuum at 60° C. to give an off-white solid (26, 6.79 g, 98.6%). 1H NMR (DMSO-d6, 300 MHz) δ ?8.12 (d, J=8.2 Hz, 1H), 7.76 (t, J=8.2 Hz, 1H), 7.48 (d, J=8.2 Hz, 1H), 6.74 (s, 1H).

Provenance & Evidence