反应详情

Bromine (8.0 g, 0.050 mol) in 48% HBr is added dropwise to a stirred solution of diethyl-5-acetyl-1,6-dihydro-6-oxo-2,3-pyridinedicarboxylate (14.05 g, 0.05 mol) in 48% HBr (200 mL). Upon completion of this bromine addition the reaction mixture is poured onto ice (200 g) and the mixture is stirred until the ice has melted. Th crude product is collected by filtration and crystallized twice from an ethyl acetate-hexane mixture (1/2) affording diethyl 5-(bromoacetyl)-1,6-dihydro-6-oxo-2,3-pyridinedicarboxylate with mp 141°-142° C.

1. additionis poured onto ice (200 g)
2. filtrationTh crude product is collected by filtration
3. customcrystallized twice from an ethyl acetate-hexane mixture (1/2)