Sodium Hydroxide → HCID 178462625, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 7-(4-ethoxycarbonyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-1-vinyl-1,8-naphthyridine-3-carboxylic acid (78 g) and aqueous 20% sodium hydroxide (1,100 ml) was refluxed with stirring for 24 hours. After cooling, the resulting crystals were collected by filtration and washed with aqueous 10% sodium hydroxide (50 ml). The crystals were added to water (600 ml) and the mixture was heated at 90° C. and the acetic acid (50 ml) was added. After treatment with charcoal, the solution was acidified with concentrated hydrochloric acid (100 ml), and cooled in an ice-bath. The resulting crystals were collected by filtration, washed with water, and recrystallized from ethanol-chloroform to give 42.5 g of 6-fluoro-1,4-dihydro-7-hydroxy-4-oxo-1-vinyl-1,8-naphthyridine-3-carboxylic acid, m.p. 256°-259° C.

Provenance & Evidence