反应详情

Into 80 ml of isopropanol were dissolved 5.5 grams of 2-(1-(3-nitrobenzylidene)-acetonyl)-2-oxo-1,3,2-dioxaphosphorinane and 2.1 grams of methyl 3-aminocrotonate and the mixture was heated to reflux for 10 hours. After the reaction, the reaction solution was concentrated in vacuo, the residue was made crystallized by addition of ethyl acetate, and crystals separated out were collected by filtration. The crude crystals were recrystallized from ethyl acetate to give 3.6 grams of methyl 2,6-dimethyl-4-(3-nitrophenyl)-5-(2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydropyridine-3-carboxylate, m. p. 221°-3° C.

1. temperaturethe mixture was heated
2. temperatureto reflux for 10 hours
3. customAfter the reaction
4. concentrationthe reaction solution was concentrated in vacuo
5. customthe residue was made crystallized by addition of ethyl acetate, and crystals
6. customseparated out
7. filtrationwere collected by filtration
8. customThe crude crystals were recrystallized from ethyl acetate