Diethyl (ethoxymethylene)malonate → HCID 1486467, compound

Participants

Reaction Steps

2-Amino-5-chlorobenzophenone (3.0 g) and diethyl ethoxymethylenemalonate (3.3 g) were reacted in the same manner as in Experimental Example 1 to give 8-benzoyl-6-chloro-3-ethoxycarbonyl-4(1H)-quinolone (2.1 g). The compound (1.4 g) was dissolved in methanol (24 ml). A 10% aqueous solution of NaOH (16 ml) was added to the solution, and the mixture was heated under reflux for 1 hour. After acidification of the mixture with a 10% aqueous solution of HCl, the precipitate was collected by filtration, washed with water and dried to give a carboxylic acid (1.2 g). The carboxylic acid (1.2 g) was suspended in diphenyl ether (30 ml), and the suspension was heated under reflux under a stream of argon at 280° C. for 3 hours. After the reaction mixture was left to cool, a mixed solvent of ether (50 parts) and n-hexane (50 parts) was added, and the crude crystal thus obtained was collected by filtration and recrystallized from chloroform-methanol-n-hexane to give 8-benzoyl-6-chloro-4(1H)-quinolone (compound 18, 0.6 g).

Provenance & Evidence