反応 #1833230

反応方程式

cesium carbonate

3,5-Difluorobenzene-1,2-diol

water

Bromochloromethane

→

title compound

収率 28.0%

4,6-Difluorobenzo[d][1,3]dioxole

収率 28.0%

溶媒

N,N-dimethylformamide

diethyl ether

反応条件

後処理

1. 1
   温度the mixture was heated
2. 2
   workup.STIRRINGstirred at 60° C. for 19 h
3. 3
   温度After cooling
4. 4
   抽出The aqueous phase was extracted again with ether (50 mL)
5. 5
   洗浄The combined extracts were washed with water (2×20 mL)
6. 6
   洗浄washed with saturated NaCl (1×10 mL)
7. 7
   乾燥dried (Na2SO4)
8. 8
   その他The bulk of the ether was removed by atmospheric distillation through a 300 mm Vigreux column
9. 9
   workup.DISTILLATIONthe product was distilled at 70-90° C.

実験手順

3,5-Difluorobenzene-1,2-diol (10 g, 69 mmol) was dissolved in dry N,N-dimethylformamide (100 mL), treated with cesium carbonate (56 g, 170 mmol) and stirred for 30 min at 20° C. Bromochloromethane (12 g, 90 mmol) was added and the mixture was heated and stirred at 60° C. for 19 h. After cooling, the mixture was shaken with water (100 mL) and diethyl ether (100 mL). The aqueous phase was extracted again with ether (50 mL). The combined extracts were washed with water (2×20 mL), washed with saturated NaCl (1×10 mL) and dried (Na2SO4). The bulk of the ether was removed by atmospheric distillation through a 300 mm Vigreux column. The pressure was reduced to 75 mmHg and the product was distilled at 70-90° C. to give the title compound as a thick oil (3.0 g, 28%): 1H NMR (400 MHz, CDCl3) δ 6.45 (m, 1H), 6.42 (d, J=2.4 Hz, 1H), 6.39 (d, J=2.4 Hz, 1H), 6.02 (s, 2H); 19F NMR (376 MHz, CDCl3) δ −117.99, −135.90; EIMS m/z 158.

出典