反応 #1339

反応方程式

Sodium t-butoxide

1-bromo-1-chloro-2,2,2-trifluoroethane

3-methylbut-1-en-1-al

tetrahydrofuran

→

5-bromo-5-chloro-4-hydroxy-2-methyl-6,6,6-trifluorohex-2-ene

溶媒

dimethyl formamide

反応条件

後処理

1. 1
   温度by external cooling under a nitrogen atmosphere
2. 2
   温度external cooling
3. 3
   その他was removed
4. 4
   その他the reaction quenched by the dropwise addition of saturated aqueous ammonium chloride solution
5. 5
   その他The mixture was then partitioned between water and diisopropyl ether
6. 6
   その他the aqueous phase separated
7. 7
   洗浄washed with diisopropyl ether (3×25 ml)
8. 8
   洗浄The organic phase was washed with brine
9. 9
   乾燥dried over anhydrous sodium sulphate
10. 10
    濃縮concentrated by evaporation under reduced pressure
11. 11
    その他After purification by a procedure similar to

実験手順

Sodium t-butoxide (1.39 g of a 42% solution in dry dimethyl formamide was added dropwise over a period of 5 minutes to a stirred mixture of 1-bromo-1-chloro-2,2,2-trifluoroethane (0.535 ml), 3-methylbut-1-en-1-al (0.538 ml) and dry tetrahydrofuran (10 ml) maintained at a temperature of -78° C. by external cooling under a nitrogen atmosphere. The mixture was then stirred for a further 40 minutes at the temperature after which the external cooling was removed and the reaction quenched by the dropwise addition of saturated aqueous ammonium chloride solution. The mixture was then partitioned between water and diisopropyl ether and the aqueous phase separated, washed with diisopropyl ether (3×25 ml), and the washings combined with the organic phase. The organic phase was washed with brine and dried over anhydrous sodium sulphate and concentrated by evaporation under reduced pressure. After purification by a procedure similar to that set out in the previous Example there was obtained 5-bromo-5-chloro-4-hydroxy-2-methyl-6,6,6-trifluorohex-2-ene (1.39 g), identified by nuclear magnetic resonance and infra-red spectroscopy.

出典