反应详情

A 50 g portion of ethyl acetoacetate in 60 ml of acetic acid was stirred at 0° C. to 10° C., as a solution of 30 g of sodium nitrite in 50 ml of water was added dropwise. When addition was complete, the mixture was stirred at 0° to 10° C. for 30 minutes and then diluted with 300 ml of ice water. The mixture was stirred for 2 hours and then extracted with 500 ml of dichloromethane. The dichloromethane layer was separated, washed with two 500 ml portions of ice water, dried, filtered and evaporated in vacuo. The residual oil was stirred vigorously with 200 ml of hexane and the resulting solid collected, washed with hexane and air dried, giving 31.4 g of 2,3-dioxobutyric acid, ethyl ester, (Z)-2-oxime.

1. additionwas added dropwise
2. additionWhen addition
3. stirringThe mixture was stirred for 2 hours
4. extractionextracted with 500 ml of dichloromethane
5. customThe dichloromethane layer was separated
6. washwashed with two 500 ml portions of ice water
7. customdried
8. filtrationfiltered
9. customevaporated in vacuo
10. stirringThe residual oil was stirred vigorously with 200 ml of hexane
11. customthe resulting solid collected
12. washwashed with hexane and air
13. customdried