反应详情

To a bright yellow suspension of ethyl 1-(2,2-dicarboethoxyvinyl)-4-oxo-4H-quinolizine-3-carboxylate (12) (750 mg, 1.94 mmol) in 5 ml ethanol was added NaBH3CN (68 mg, 1.08 mmol). The reaction mixture turned red and all solid material dissolved. Stirring was continued for 1 h, and the reaction mixture was poured into 50 ml of water. Ethanol was added to the aqueous suspension until a clear solution was obtained, which was extracted three times with 100 ml dichloromethane. The organic solvent was evaporated and the crude product was purified by flash chromatography to give ethyl 1-(2,2-dicarboethoxyethyl)-4-oxo-4H-quinolizine-3-carboxylate (13) as a bright yellow solid (275 mg, 36%). M.p. 105-108° C. 1H NMR (δ, CDCl3): 1.22 (t, J=7 Hz, 6H), 1.41 (t, J=7 Hz, 3H), 3.41 (d, J=7 Hz, 2H), 3.65 (t, J=7 Hz, 1H), 4.10-4.25 (m, 4H), 4.41 (q, J=7 Hz, 2H), 7.23 (m, 1H), 7.70 (m, 1H), 7.84 (d, J=8 Hz, 1H), 8.33 (s, 1H), 9.50 (d, J=7 Hz, 1H). MS: m/z 389.1466; required for C20H23NO7: 389.1475.

1. dissolutionall solid material dissolved
2. customwas obtained
3. extractionwhich was extracted three times with 100 ml dichloromethane
4. customThe organic solvent was evaporated
5. customthe crude product was purified by flash chromatography