反应详情

A 500-mL round bottom flask was charged with methyl 4-oxobutanoate (8.52 g, 73.3 mmol), dioxane (0.7 mL) in diethyl ether (70 mL). Bromine (3.94 mL, 77.0 mmol) was added at room temperature over 1.5 h. After this time, the mixture was diluted with dichloromethane (250 mL) and solid sodium bicarbonate (13.6 g, 161 mmol) was added. After stirring for 2 h the mixture was filtered and the filtrate concentrated under reduced pressure to afford the title compound (15.3 g, 100%) as a colorless oil. MW=195.01. 1H NMR (CDCl3, 300 MHz) δ 9.54 (s, 1H), 4.68 (dd, J=6.9, 6.6 Hz, 1H), 3.74 (s, 3H), 3.25 (dd, J=17.4, 7.2 Hz, 1H), 2.94 (dd, J=17.1, 6.6 Hz, 1H).

1. additionwas added
2. filtrationwas filtered
3. concentrationthe filtrate concentrated under reduced pressure