Phenylhydrazine → HCID 178515215, compound

Participants

Reaction Steps

To a slurry of 1.5 g of ethyl 4-hydroxy-1,5-naphthyridine-3-carboxylate (prepared according to J. Inorg. Nucl. Chem., (1966) 28, 2439) in 17 ml of dimethylformamide is added 0.907 g of oxalyl chloride in 2 ml of methylene chloride while maintaining the reaction temperature between -25° and -30°. The mixture is stirred at -25° for 35 minutes. A solution of 0.995 g of diisopropylethylamine and 0.833 g of phenylhydrazine in 4 ml of methylene chloride is added to the mixture in 8 minutes at -30° to -25°. The mixture is then stirred for 30 minutes at -25°, 20 minutes at 0° and 40 minutes at 23°. The resultant dark purple solution is poured into 60 ml of water. Dark precipitate is collected, washed with water and crystallized from methanol to yield 2-phenyl-pyrazolo[4,3-c] [1,5]naphthyridin-3(5H)-one, m.p. 314°-316°.

Provenance & Evidence