反応 #218552

反応方程式

3-bromo benzo[b]thiophene

nitric acid

ice water

ethyl acetate

→

3-Bromo-2-nitro-benzo[b]thiophene

溶媒

TFA

dichloromethane

dichloromethane

反応条件

後処理

1. 1
   workup.ADDITIONThen pour
2. 2
   抽出Extract with dichloromethane (3×500 mL)
3. 3
   乾燥the organic layer dry over MgSO4
4. 4
   その他Evaporation
5. 5
   その他give a yellow solid
6. 6
   その他The resulting yellow solid triturate with diethyl ether
7. 7
   その他to give a yellow solid

実験手順

Add dropwise fuming nitric acid (90%, 8.6 mL, 183 mmol) to a mixture of 3-bromo benzo[b]thiophene (39 g, 183 mmol) in TFA (100 mL) and dichloromethane (400 mL) at 0° C. The reaction turn greenish, then yellow precipitates. To this reaction mixture, add dichloromethane (200 mL) and the reaction stir at 0° C. for 30 min. Then pour the reaction into ice-water (2L). Extract with dichloromethane (3×500 mL) and the organic layer dry over MgSO4. Evaporation give a yellow solid. The resulting yellow solid triturate with diethyl ether to give a yellow solid. (Total: 34.8 g, 73%). Mass spectrum (m/e): 259(M+1); 1HNMR(300 MHz, DMSO-d6) δ ppm: 7.70(tt, 2H), 8.04(d, 1H), 8.17(d, 1H). 13CNMR(75 MHz, DMSO-d6) δ ppm: 112.5, 124.8, 126.9, 127.9, 131.3, 137.0, 137.2, 166.1.

出典