Hydrochloric Acid → HCID 14423302, compound

Participants

Reaction Steps

Saponify 7-ethoxycarbonyl-10-(3-chlorophenyl)-6,7,8,9-tetrahydrobenzo[b] [1,8]naphthyridin-5(10H)-one (7.1 g) with potassium hydroxide (1.10 g) in a solvent of ethanol and water (142 ml, 9:1 by volume). After 21 hours at 25° C., add water (200 ml), cool the resulting solution in ice, and acidify (pH 2) the solution with concentrated hydrochloric acid. Collect the resulting precipitate on a filter, and crystallize it from ethanol to provide 7-carboxy-10-(3-chlorophenyl)-6,7,8,9-tetrahydrobenzo[b] [1,8]naphthyridin-5(10H)-one, m.p. 279°-280.5° C.

Provenance & Evidence