反应详情

A mixture of crude t-butyl 2-(2-nitro-4-trifluoromethylbenzoyl)-3-oxobutanoate (9.1 g) and 4-toluenesulphonic acid (0.1 g) in dry toluene (100 ml) was stirred and heated at reflux for 3 hours. The cooled mixture was extracted with aqueous sodium hydroxide solution (2M, 2×50 ml) and water (2×50 ml). The combined aqueous extracts were acidified to pH 1 and extracted with ether (3×100 ml). The combined organic layers were washed with water (50 ml), dried (anhydrous sodium sulphate) and filtered. The filtrate was evaporated to dryness and the residue was recrystallized from petroleum spirit (bp 60°-80° C.) to give 1-(2-nitro-4-trifluoromethylphenyl)-butan-1,3-dione (4.6 g) as an off white solid mp 80°-81° C.

1. temperatureheated
2. temperatureat reflux for 3 hours
3. extractionThe cooled mixture was extracted with aqueous sodium hydroxide solution (2M, 2×50 ml) and water (2×50 ml)
4. extractionextracted with ether (3×100 ml)
5. washThe combined organic layers were washed with water (50 ml)
6. dry with materialdried (anhydrous sodium sulphate)
7. filtrationfiltered
8. customThe filtrate was evaporated to dryness
9. customthe residue was recrystallized from petroleum spirit (bp 60°-80° C.)