Sodium Hydroxide → 3-Amino-6-fluoro-2-(4-chlorophenyl)-4-quinolinecarboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of 7 g of 5-fluoroisatin in 58 ml of water was added a solution of 9.36 g of sodium hydroxide in 33 ml of water. The solution was heated to 85° C. and a solution of 12 g of 2-amino-1-(4-chlorophenyl)ethanone hydrochloride in a mixture of 92 ml of ethanol and 40 ml of tetrahydrofuran and 92 ml of water was added drop-wise over 2 hours. After the addition was complete, the solution was refluxed for an additional 30 minutes and then the ethanol and tetrahydrofuran were removed by distillation. The mixture was cooled to 20° C. and filtered through celite. The filtrate was acidified to pH 4 with acetic acid. The solid was filtered off, washed with water and dried, giving 12.8 g of the desired compound as a yellow solid, mp 241°-243° C.

Provenance & Evidence