Ethyl Acetate → Ethyl 1-bromo-4-oxo-4H-quinolizine-3-carboxylate

Participants

Reaction Steps

To a solution of ethyl 4-oxo-4H-quinolizine-3-carboxylate (1) (2.33 g, 10.7 mmol) in 20 ml acetic acid was rapidly added a solution of bromine (1.9 g, 12 mmol) in 10 ml acetic acid. The reaction was complete after 5 min, as indicated by thin layer chromatography (ethyl acetate). The solvent was evaporated in vacuo and the remaining yellow solid was dissolved in 20 ml dichloromethane. To this solution, silica gel (3 g) was added and the solvent was evaporated in vacuo. The silica gel was poured on a prepacked column and eluted with ethyl acetate to give ethyl 1-bromo-4-oxo-4H-quinolizine-3-carboxylate (9) as a bright yellow solid (2.1 g, 71%). M.p. 156-158° C. 1H NMR (δ, CDCl3): 1.43 (t, J=7 Hz, 3H), 4.43 (q, J=7 Hz, 2H), 7.03 (dd, J=7 Hz, J=7 Hz, 1H), 7.30 (dd, J=7 Hz, 2H), 7.80 (dd, J=7 Hz, J=7 Hz, 1H), 8.63 (s, 1H), 9.49 (d, J=7 Hz). MS: m/z 294.9839; required for C12H10BrNO3: 294.9843.

Provenance & Evidence