反応 #470555

反応方程式

4-Bromo-2-methyl-phenol

triethylamine

methyl chloroformate

→

4-bromo-2-methylphenyl methyl carbonate

収率 86.2%

溶媒

dichloromethane

反応条件

後処理

1. 1
   その他The reaction was quenched with water
2. 2
   その他the layers separated
3. 3
   抽出The aqueous layer was extracted with dichloromethane
4. 4
   乾燥the combined organic extracts was dried over Na2SO4
5. 5
   ろ過filtered
6. 6
   濃縮concentrated in vacuo
7. 7
   その他to yield an oil that
8. 8
   その他was purified by silica gel chromatography (10% ethyl acetate/hexane)

実験手順

4-Bromo-2-methyl-phenol (3.63 g, 19.41 mmol) was dissolved in dichloromethane (18 mL) and triethylamine (5.41 mL, 38.80 mmol), cooled to 0° C., then treated with methyl chloroformate (2.25 mL, 29.12 mmol) and allowed to warm to room temperature over 2 h. The reaction was quenched with water and the layers separated. The aqueous layer was extracted with dichloromethane and the combined organic extracts was dried over Na2SO4, filtered, and concentrated in vacuo to yield an oil that was purified by silica gel chromatography (10% ethyl acetate/hexane) to yield 4-bromo-2-methylphenyl methyl carbonate (4.1 g, 86% yield) as a white solid. 1H NMR (400.0 MHz, DMSO-d6) δ 7.56 (d, J=2.1 Hz, 1H), 7.44 (dd, J=2.3, 8.6 Hz, 1H), 7.18 (d, J=8.6 Hz, 1H), 3.84 (s, 3H), 2.15 (s, 3H).

出典