反应详情

温度

55 °C

To a 150 mL flask was added diethyl 2-[2-(4-bromophenyl)-2-oxoethyl]-2-(2-methoxyethyl)malonate (1.59 g, 3.59 mmol) dissolved in acetone (16 mL) and ethanol (16 mL), followed by addition of 1N aqueous sodium hydroxide solution (3.6 mL). The reaction mixture was then heated at 55° C. for 3 h. The reaction mixture was concentrated in vacuo to remove solvents, the residue redissolved in dimethoxyethane (32 mL), and the reaction mixture heated at 80° C. for 3 h. The reaction mixture was cooled to rt, diluted with ethyl acetate (50 mL) and water (50 mL), and stirred for 15 minutes until almost all color was extracted into the organic layer. The layers were separated, the aqueous layer was extracted with additional ethyl acetate (50 mL), and the combined organic layers were washed with saturated aqueous sodium chloride solution (50 mL), dried over anhydrous sodium sulfate, and concentrated in vacuo, to afford ethyl 4-(4-bromophenyl)-2-(2-methoxyethyl)-4-oxobutanoate (1.06 g, 86%). No further purification of this material was required. LC-MS ret. time 3.18 min, m/z 342.8 (MH+); 1H NMR (300 MHz, CDCl3) δ 1.35 (t, 3H), 1.77-1.92 (m, 1H), 1.94-2.10 (m, 1H), 3.05-3.2 (m, 2H), 3.35-3.50 (m, 3H), 4.09-4.25 (m, 2H), 7.60 (d, 2H), 7.83 (d, 2H).

1. concentrationThe reaction mixture was concentrated in vacuo
2. customto remove solvents
3. dissolutionthe residue redissolved in dimethoxyethane (32 mL)
4. temperaturethe reaction mixture heated at 80° C. for 3 h
5. temperatureThe reaction mixture was cooled to rt
6. additiondiluted with ethyl acetate (50 mL) and water (50 mL)
7. extractionwas extracted into the organic layer
8. customThe layers were separated
9. extractionthe aqueous layer was extracted with additional ethyl acetate (50 mL)
10. washthe combined organic layers were washed with saturated aqueous sodium chloride solution (50 mL)
11. dry with materialdried over anhydrous sodium sulfate
12. concentrationconcentrated in vacuo