反应详情

温度

50 °C

A mixture of magnesium turnings (4.8 g) and carbon tetrachloride (2 ml) in pure ethanol (30 ml) was stirred and warmed gently to 50° C. until the reaction was initiated (effervescence observed). Ether (100 ml) was added cautiously with stirring. A solution of t-butyl 3-oxobutanoate (31.6 g) in ether (100 ml) was added dropwise at such a rate as to maintain the mixture at reflux. Stirring and heating at reflux was continued for 2 hours. A solution of 2-nitro-4-trifluoromethylbenzoyl chloride (50.7 g) in ether (100 ml) was added dropwise and the resultant solution was stirred and heated at reflux for 25 hours. The cooled reaction mixture was treated with hydrochloric acid (2M, 100 ml) with stirring and the two layers were separated. The organic phase was extracted with aqueous sodium hydroxide solution (2M, 2×50 ml) and water (4×50 ml). The combined aqueous layers were acidified to pH 1 and extracted with ether (2×100 ml). The combined organic layers were washed with water (50 ml), dried (anhydrous sodium sulphate) and filtered. The filtrate was evaporated to dryness to give t-butyl 2-(2-nitro-4-trifluoromethylbenzoyl)-3-oxobutanoate (62.2 g) as a crude red oil which was not further purified.

1. stirringwith stirring
2. temperatureto maintain the mixture
3. temperatureat reflux
4. stirringStirring
5. temperatureheating
6. temperatureat reflux
7. temperatureheated
8. temperatureat reflux for 25 hours
9. customThe cooled reaction mixture
10. stirringwith stirring
11. customthe two layers were separated
12. extractionThe organic phase was extracted with aqueous sodium hydroxide solution (2M, 2×50 ml) and water (4×50 ml)
13. extractionextracted with ether (2×100 ml)
14. washThe combined organic layers were washed with water (50 ml)
15. dry with materialdried (anhydrous sodium sulphate)
16. filtrationfiltered
17. customThe filtrate was evaporated to dryness