反应详情

An oven-dried 50 ml three-necked round-bottom flask was purged with argon and charged with sodium hydride (200 mg, 60% suspension in oil, 5 mmol and washed with hexane) and 10 ml dry DMF. To this suspension, m-nitrophenol (626 mg, 4.5 mmol) was added in one portion. After gas evolution had ceased, ethyl 8-chloro-4-oxo-4H-quinolizine-3-carboxylate (2) (1.00 g, 4 mmol) was added in one portion and stirring was continued at room temperature for 2 h. When the reaction was complete as indicated by thin layer chromatography (ethyl acetate), the reaction mixture was poured into 250 ml of water. The aqueous layer was extracted three times with 200 ml dichloromethane, and the combined organic layers were washed three times with 200 ml water. The organic solvent was evaporated and the crude product was stirred overnight with 30 ml ether. Filtration gave a bright yellow solid (950 mg, 67%). M.p. 161-163° C. 1H NMR (δ, CDCl3): 1.42 (t, J=7 Hz, 3H), 4.41 (q, J=7 Hz, 2H), 6.39 (d, J=8 Hz, 1H), 6.70 (d, J=2 Hz, 1H), 6.99 (dd, J=0.5 Hz, J=7 Hz, 1H), 7.55 (d, J=7 Hz, 1H), 7.72 (dd, J=8 Hz, J=8 Hz, 1H), 8.07 (s, 1H), 8.24 (d, J=8 Hz, 1H), 8.32 (d, J=8 Hz, 1H), 9.43 (d, J=7 Hz, 1H). MS: m/z 354.0850; required for C18H14N2O6: 354.0852.

1. customAn oven-dried 50 ml three-necked round-bottom flask was purged with argon
2. extractionThe aqueous layer was extracted three times with 200 ml dichloromethane
3. washthe combined organic layers were washed three times with 200 ml water
4. customThe organic solvent was evaporated
5. stirringthe crude product was stirred overnight with 30 ml ether
6. filtrationFiltration