反应详情

温度

50 °C

Sodium tert-pentoxide (33.52 g) was added to mesitylene (280 ml) and the mixture heated to 50° C. To the suspension was added ethyl acetoacetate (39.61 g) over 10 minutes. The reaction mixture exothermed to about 60° C. The thick slurry was heated to 70° C. and 1,2,3-trifluoro-4-nitrobenzene (25.0 g) added. The mixture exothermed to 80° C. The mixture was held at 70-80° C. for 3 hours, then allowed to cool to ambient and left overnight. To the mixture was added hydrochloric acid (6% w/w, 100 ml), until the pH reached 1. The aqueous layer was separated and discarded and the organic layer washed twice with hydrochloric acid 6% w/w, 90 ml), then with aqueous sodium bicarbonate (2.3% w/w, 37.5 ml) and finally water (75 ml). To the organic layer was added further mesitylene (53 ml) and the mixture distilled on a rotary evaporator (10 mbar, bath 60° C.) to give a solution of ethyl 2-(2,3-difluoro-6-nitrophenyl)-3-oxobutanoate in mesitylene (90 ml containing 36.22 g of ethyl 2-(2,3-difluoro-6-nitrophenyl)-3-oxobutanoate).

1. customexothermed to about 60° C
2. temperatureThe thick slurry was heated to 70° C.
3. customexothermed to 80° C
4. temperatureto cool to ambient and
5. waitleft overnight
6. customThe aqueous layer was separated
7. washthe organic layer washed twice with hydrochloric acid 6% w/w, 90 ml), then with aqueous sodium bicarbonate (2.3% w/w, 37.5 ml) and finally water (75 ml)
8. additionTo the organic layer was added further mesitylene (53 ml)
9. distillationthe mixture distilled on a rotary evaporator (10 mbar, bath 60° C.)