반응 #82821

반응 방정식

4-nitrobenzamide oxime

ethyl chlorooxoacetate

borontrifluoride

→

5-ethoxycarbonyl-3-(4-nitrophenyl)-1,2,4-oxadiazole

용매

dioxane

반응 조건

후처리

1. 1
   온도was refluxed for 1 hour
2. 2
   온도The whole mixture was refluxed for 12 hours
3. 3
   기타the solvent was evaporated in vacuo
4. 4
   workup.ADDITIONThe residue was diluted with ethyl acetate (100 ml)
5. 5
   세척washed with a saturated potassium carbonate aqueous solution
6. 6
   건조dried over magnesium sulfate
7. 7
   기타evaporated in vacuo
8. 8
   기타The residue was purified by column chromatography on silica gel with a mixture of dichloromethane and hexane (1:1) as eluent
9. 9
   workup.ADDITIONThe fractions containing the object product
10. 10
    기타were collected
11. 11
    기타evaporated in vacuo

실험 절차

A mixture of 4-nitrobenzamide oxime (4 g) and ethyl chlorooxoacetate (3.01 g) in dioxane (200 ml) was refluxed for 1 hour, and then borontrifluoride (1 ml) was added thereto. The whole mixture was refluxed for 12 hours. After being cooled to room temperature, the solvent was evaporated in vacuo. The residue was diluted with ethyl acetate (100 ml), washed with a saturated potassium carbonate aqueous solution, dried over magnesium sulfate and evaporated in vacuo. The residue was purified by column chromatography on silica gel with a mixture of dichloromethane and hexane (1:1) as eluent. The fractions containing the object product were collected and evaporated in vacuo to afford 5-ethoxycarbonyl-3-(4-nitrophenyl)-1,2,4-oxadiazole.

출처