Sodium Hydroxide → Ethyl 4-(4-bromophenyl)-4-oxo-2-(2-phenylethyl)butanoate

関与物質

反応条件

反応手順

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).

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