反应详情

Ethyl 4-oxo-4H-quinolizine-3-carboxylate (1) (1 g, 4.0 mmol) was dissolved in 2 ml DMF followed by the addition of POCl3 (1.0 ml, 11 mmol). The reaction mixture was stirred for 1 h, poured into 100 ml water and extracted three times with 100 ml dichloromethane. Evaporation of the organic solvent gave a sticky yellow solid, which was further purified by flash chromatography (ethyl acetate), followed by overnight stirring with 10 ml ether to remove the last traces of DMF. Filtration of the suspension and drying in vacuo gave a bright yellow powder (920 mg, 93%). M.p. 179-181° C. 1H NMR (δ, CDCl3): 1.43 (t, J=7 Hz), 4.42 (q, J=7 Hz), 7.51 (dd, J=7 Hz, J=7 Hz, 1H), 8.06 (dd, J=7, J=7 Hz, 1H), 8.80 (s, 1H), 9.57 (d, J=7 Hz), 9.90 (s, 1H). MS: m/z 245.0683; required for C13H11NO4: 245.0688.

1. extractionextracted three times with 100 ml dichloromethane
2. customEvaporation of the organic solvent
3. customgave a sticky yellow solid, which
4. customwas further purified by flash chromatography (ethyl acetate)
5. waitfollowed by overnight
6. stirringstirring with 10 ml ether
7. customto remove the last traces of DMF
8. filtrationFiltration of the suspension
9. customdrying in vacuo