反応 #9038

反応方程式

dimethyl sulfate

ethyl 6-methylsalicylate

lithium hydroxide monohydrate

→

ethyl 2-methoxy-6-methylbenzoate

収率 91.0%

溶媒

diethyl ether

THF

反応条件

後処理

1. 1
   温度to reflux for 1 hour
2. 2
   洗浄washed with saturated aqueous NaHCO3 (4×10 mL)
3. 3
   乾燥dried (MgSO4)
4. 4
   濃縮concentrated
5. 5
   その他Purification of the crude material by column chromatography on silica gel (9:1 hexanes-EtOAc)

実験手順

To a solution of ethyl 6-methylsalicylate (1.27 g, 6.97 mmol) in THF (35 mL) was added lithium hydroxide monohydrate (0.594 g, 14.2 mmol) followed by dimethyl sulfate (1.00 mL, 10.6 mmol). The resultant mixture was heated to reflux for 1 hour then cooled to room temperature. The mixture was diluted with diethyl ether (70 mL), washed with saturated aqueous NaHCO3 (4×10 mL), dried (MgSO4) and concentrated. Purification of the crude material by column chromatography on silica gel (9:1 hexanes-EtOAc) provided 1.23 g (91%) of ethyl 2-methoxy-6-methylbenzoate as a white solid. 1H NMR (CDCl3) δ 1.38 (t, 3H, J=7.2 Hz), 2.30 (s, 3H), 3.82 (s, 3H), 4.40 (q, 2H, J=7.2 Hz), 6.76 (d, 1H, J=8.4 Hz), 6.79 (d, 1H, J=7.8 Hz), 7.23 (dd, 1H, J=7.8, 8.4 Hz).

出典