反应详情

6.1 kg of potassium carbonate were added at 20°-25° C. to a mixture of 4.69 kg of ethyl 2-acetyl-2-hydroxyiminoacetate (equal to 4.21 kg of pure product) in 21 liters of anhydrous pure acetone and after stirring the suspension for 10 minutes, 3.72 kg of dimethyl sulfate were added at 20°-25° C. The mixture was poured into 126 liters of demineralized water and was extracted 4 times with 5 liters and then with 2 liters of methylene chloride. The combined extracts were washed with 10 liters of demineralized water, were dried and vacuum filtered. The filter was rinsed with 2 liters of methylene chloride and the filtrate was evaporated to dryness under reduced pressure to obtain 4.88 kg of ethyl 2-acetyl-2-methoxyiminoacetate with an Rf=0.7 (thin layer chromatography -9- 1 methylene chloride-ethyl acetate eluant). The product was identical to that product in Step A of Example 3.

1. extractionwas extracted 4 times with 5 liters
2. washThe combined extracts were washed with 10 liters of demineralized water
3. customwere dried
4. filtrationvacuum filtered
5. washThe filter was rinsed with 2 liters of methylene chloride
6. customthe filtrate was evaporated to dryness under reduced pressure