反应详情

Sodium acetate (30 g, 0.37 mol) is added to a stirred mixture of diethyl(ethoxymethylene)oxalacetate (87 g, 0.36 mol) and acetoacetamide (36 g, 0.36 mol) in absolute ethanol (300 mL). After stirring the reaction mixture for 30 minutes, the ethanol is distilled off under reduced pressure, the residue acidified to pH 2 with dilute aqueous hydrochloric acid and the resulting solid filtered off. Crystallization from an ethanol-water mixture affords diethyl 5-acetyl-1,6-dihydro-6-oxo-2,3-pyridinedicarboxylate as crystals mp 101°-110° C.

1. distillationthe ethanol is distilled off under reduced pressure
2. filtrationthe resulting solid filtered off
3. customCrystallization from an ethanol-water mixture