反应详情

温度

-75 °C

To a solution of 19.4 g. (0.19 m) diisopropylamine in 100 ml. of dry tetrahydrofuran is added dropwise 12.3 g. (0.19 m) n-butyl lithium at -75° C. under nitrogen. Stirring is continued for 1/2 hour when a solution of 30 g. (0.16 m) 4-ethyl-2-phenyl-gamma-butyrolactone in 50 ml. tetrahydrofuran is added dropwise in one hour. The resulting mixture is further stirred for 1/2 hour and a mixture of 33 g. (0.19 m) dibromomethane and 34 g. (0.19 m) hexamethylphosphoramide is added dropwise. The reaction temperature is maintained at -75° C. throughout the additions. The reaction mixture is stirred at room temperature overnite. It is then poured into 500 ml. of saturated ammonium chloride solution and extracted with ether. The combined ether extracts are dried over sodium sulfate and filtered. Solvent is removed under vacuum to give 39 g. of an oil which is further purified by bulb-to-bulb vacuum distillation to give 26 g. of pure product.

1. customat -75° C.
2. stirringThe resulting mixture is further stirred for 1/2 hour
3. additiona mixture of 33 g
4. stirringThe reaction mixture is stirred at room temperature overnite
5. additionIt is then poured into 500 ml
6. extractionof saturated ammonium chloride solution and extracted with ether
7. dry with materialThe combined ether extracts are dried over sodium sulfate
8. filtrationfiltered
9. customSolvent is removed under vacuum
10. customto give 39 g
11. distillationof an oil which is further purified by bulb-to-bulb vacuum distillation
12. customto give 26 g