反応 #10797

反応方程式

sulfuric acid

acetyl chloride

aluminum chloride

2-methyl-2-phenyl-propionic acid ethyl ester

→

2-(4-acetyl-phenyl)-2-methyl-propionic acid ethyl ester

収率 47.0%

溶媒

carbon disulfide

反応条件

後処理

1. 1
   温度The reaction mixture was refluxed for 2 hours
2. 2
   workup.ADDITIONpoured into ice
3. 3
   その他The mixture was partitioned
4. 4
   抽出The aqueous layer was extracted with ethyl acetate
5. 5
   洗浄The solution of ethyl acetate was washed with hydrochloric acid (0.5M), saturated solution of sodium bicarbonate and brine
6. 6
   乾燥dried over sodium sulfate
7. 7
   濃縮concentrated
8. 8
   その他The crude product was purified by flash chromatography
9. 9
   洗浄Elution with ethyl acetate (33%, v/v, in hexane)

実験手順

Ex-77A: To a mixture of aluminum chloride (2.8 g, 20.8 mmol) in carbon disulfide (50 mL) was added acetyl chloride (0.74 mL, 10.4 mmol) followed by addition of 2-methyl-2-phenyl-propionic acid ethyl ester (1.0 g, 5.2 mmol). The reaction mixture was refluxed for 2 hours and then poured into ice containing sulfuric acid (6M). The mixture was partitioned. The aqueous layer was extracted with ethyl acetate. The solution of ethyl acetate was washed with hydrochloric acid (0.5M), saturated solution of sodium bicarbonate and brine, dried over sodium sulfate and concentrated. The crude product was purified by flash chromatography. Elution with ethyl acetate (33%, v/v, in hexane) gave 2-(4-acetyl-phenyl)-2-methyl-propionic acid ethyl ester (0.57 g, 47%). 1H NMR (CDCl3) δ 7.92 (d, J=7.6 Hz, 2H), 7.42 (d, J=7.6 Hz, 2H), 4.13 (q, J=7.2 Hz, 2H), 2.59 (s, 3H), 1.61 (s, 3H), 1.59 (s, 3H), 1.18 (t, J=7.2 Hz, 3H).

出典