反応 #88148

反応方程式

1-bromo-4-(perfluoroethoxy)benzene

THF

Ethyl chloroformate

→

ethyl 4-(perfluoroethoxy)benzoate

収率 50.2%

溶媒

EtOAc

反応条件

後処理

1. 1
   その他To an oven-dried 500-mL round bottom flask equipped with a stirring bar
2. 2
   温度cooled in an ice bath for 10 min
3. 3
   workup.ADDITIONA solution of 1.3 M isopropylmagnesium chloride-lithium chloride complex (30 mL, 38.6 mmol) was added over 15 min
4. 4
   その他The ice bath was removed after 1 hour
5. 5
   温度The reaction was cooled in an ice bath
6. 6
   workup.ADDITION1.3 M isopropylmagnesium chloride-lithium chloride complex (5 mL) was added
7. 7
   その他The ice bath was removed after 20 min
8. 8
   workup.STIRRINGstirred at room temperature for 9 hours
9. 9
   温度The reaction was warmed slightly during the addition
10. 10
    workup.STIRRINGwas stirred at room temperature overnight
11. 11
    洗浄washed with saturated aqueous ammonium chloride
12. 12
    抽出The aqueous layer was extracted three times with EtOAc
13. 13
    乾燥The organic layers were dried over anhydrous sodium sulfate
14. 14
    ろ過filtered
15. 15
    濃縮concentrated
16. 16
    その他to give a yellow liquid, which
17. 17
    その他was purified by flash chromatography (0-0, 0-4, 4-10% EtOAc/hexanes)

実験手順

To an oven-dried 500-mL round bottom flask equipped with a stirring bar was added 1-bromo-4-(perfluoroethoxy)benzene (9.35 g, 32.1 mmol) and anhydrous THF (200 mL). The flask was placed under nitrogen and cooled in an ice bath for 10 min. A solution of 1.3 M isopropylmagnesium chloride-lithium chloride complex (30 mL, 38.6 mmol) was added over 15 min. The ice bath was removed after 1 hour, and the reaction was warmed to room temperature and stirred overnight. GC/MS showed the presence of starting material. The reaction was cooled in an ice bath and 1.3 M isopropylmagnesium chloride-lithium chloride complex (5 mL) was added. The ice bath was removed after 20 min and stirred at room temperature for 9 hours. Ethyl chloroformate (3.4 mL, 35.3 mmol) was added in a slow, steady stream. The reaction was warmed slightly during the addition and was stirred at room temperature overnight. The reaction was diluted with EtOAc and washed with saturated aqueous ammonium chloride. The aqueous layer was extracted three times with EtOAc. The organic layers were dried over anhydrous sodium sulfate, filtered, and concentrated to give a yellow liquid, which was purified by flash chromatography (0-0, 0-4, 4-10% EtOAc/hexanes) to provide ethyl 4-(perfluoroethoxy)benzoate as a yellow liquid (4.58 g, 50%): 1H NMR (400 MHz, CDCl3) δ 8.10 (d, J=8.8 Hz, 2H), 7.28 (d, J=8.7 Hz, 2H), 4.39 (q, J=7.1 Hz, 2H), 1.40 (t, J=7.1 Hz, 3H); 19F NMR (376 MHz, CDCl3) δ −86.05, −87.84; ESIMS m/z 284 ([M+11]+).

出典