反応 #470514

反応方程式

2-Ethyl-4-fluorophenyl methyl carbonate

H2SO4

KNO3

→

2-ethyl-4-fluoro-5-nitrophenyl methyl carbonate

収率 58.0%

反応条件

後処理

1. 1
   温度maintaining the internal temperature below 5° C
2. 2
   workup.ADDITIONpoured on ice water
3. 3
   抽出The aqueous layer was extracted with dichloromethane (3×10 mL)
4. 4
   乾燥dried over Na2SO4
5. 5
   ろ過filtered
6. 6
   濃縮concentrated
7. 7
   その他Purification by silica gel chromatography (10% ethyl acetate/hexane)

実験手順

2-Ethyl-4-fluorophenyl methyl carbonate (2.4 g, 12.11 mmol) was added dropwise to H2SO4 (7.2 mL) to generate a yellow homogeneous solution. The solution was then cooled to 0° C. and KNO3 (1.469 g, 14.53 mmol) was added portion-wise maintaining the internal temperature below 5° C. The reaction was stirred for 2 h and then poured on ice water. The aqueous layer was extracted with dichloromethane (3×10 mL), dried over Na2SO4, filtered and concentrated. Purification by silica gel chromatography (10% ethyl acetate/hexane) provided 2-ethyl-4-fluoro-5-nitrophenyl methyl carbonate (1.7 g, 58% yield). 1H NMR (400.0 MHz, DMSO-d6) δ 8.20 (d, J=6.8 Hz, 1H), 7.64 (d, J=12.1 Hz, 2H), 3.88 (s, 3H), 2.62 (q, J=7.5 Hz, 1H), 1.15 (t, J=7.5 Hz, 3H).

出典