Ethyl bromoacetate → Ethyl 8-[1,1-dicarbomethoxy-2-carboethoxy-ethyl]-4-Oxo-4H-Quinolizine-3-Carboxylate

Participants

Reaction Steps

An oven-dried 50 ml three-necked round-bottom flask equipped with a reflux condenser was charged with NaH (160 mg, 60% suspension in oil, 4 mmol, washed with hexane) and 10 ml THF. Ethyl 8-(dicarbomethoxymethyl)-4-oxo-4H-quinolizine-3-carboxylate (19) (700 mg, 2 mmol) was added in three portions and stirring was continued for 1 h, followed by addition of ethyl bromoacetate (0.5 ml, 5.3 mmol). The reaction mixture was refluxed overnight, cooled to room temperature and poured into 100 ml water. The aqueous layer was extracted three times with 100 ml dichloromethane. The organic solvent was evaporated and the crude product was purified by flash chromatography (ethyl acetate) to give a yellow viscous oil (630 mg, 74%). 1H NMR (δ, CDCl3): 1.24 (t, J=7 Hz, 3H), 1.42 (t, J=7 Hz, 3H), 3.39 (s, 2H), 3.84 (s, 6H), 4.14 (q, J=7 Hz, 2H), 4.41 (q, J=7 Hz, 2H), 6.63 (d, J=8 Hz, 1H), 7.14 (dd, J=2 Hz, J=7 Hz, 1H), 7.61 (d, J=2 Hz, 1H), 8.40 (d, J=8 Hz, 1H), 9.29 (d, J=8 Hz, 1H). MS: m/z 433.1363; required for C21H21NO9: 433.1372.

Provenance & Evidence