Réaction #9620

Équation de réaction

diethyl 2-[2-(4-bromophenyl)-2-oxoethyl]-2-(2-phenylethyl)malonate

sodium hydroxide

→

ethyl 4-(4-bromophenyl)-4-oxo-2-(2-phenylethyl)butanoate

Rendement 65.0%

Solvants

acetone

ethanol

Conditions de réaction

Traitement

1. 1
   AutreSolvent was then removed under reduced pressure via rotary evaporation
2. 2
   Concentrationthe resulting residue was further concentrated under high vacuum for 1 h
3. 3
   workup.DISSOLUTIONThe residue was redissolved in dimethoxyethane (18.5 mL)
4. 4
   Températurethe solution was heated at 80° C. for 2.5 h
5. 5
   TempératureThe mixture was cooled to rt
6. 6
   workup.ADDITIONdiluted with ethyl acetate
7. 7
   Lavagewashed with water
8. 8
   SéchageThe organic layer was dried over anhydrous sodium sulfate
9. 9
   Concentrationconcentrated under high vacuum
10. 10
    AutreThe resulting residue was purified by flash chromatography (Biotage flash 75, 10:90 ethyl acetate/hexane)

Mode opératoire

To a solution of diethyl 2-[2-(4-bromophenyl)-2-oxoethyl]-2-(2-phenylethyl)malonate (7.89 g, 17.1 mmol) in acetone (18.5 mL) and ethanol (17.0 mL) was added 1 N aqueous sodium hydroxide solution (17.1 mL), and the resulting solution was heated at 50° C. for 3 h. Solvent was then removed under reduced pressure via rotary evaporation and the resulting residue was further concentrated under high vacuum for 1 h. The residue was redissolved in dimethoxyethane (18.5 mL) and the solution was heated at 80° C. for 2.5 h. The mixture was cooled to rt, diluted with ethyl acetate, and washed with water. The organic layer was dried over anhydrous sodium sulfate and concentrated under high vacuum. The resulting residue was purified by flash chromatography (Biotage flash 75, 10:90 ethyl acetate/hexane) to afford ethyl 4-(4-bromophenyl)-4-oxo-2-(2-phenylethyl)butanoate (4.32 g, 65%). LC-MS ret. time 3.79 min, m/z 389.2 (MH+); 1H NMR (300 MHz, CDCl3) δ 1.20 (t, 3H), 1.78–1.94 (m, 2H), 2.62 (t, 2H), 2.86–3.01 (m, 2H), 3.26–3.36 (m, 1H), 4.10 (q, 2H), 7.05–7.11 (m, 3H), 7.18–7.23 (m, 2H), 7.51 (d, 2H), 7.72 (d, 2H).

Source