Reaktion #51528

Reaktionsgleichung

ethyl malonate

aluminium chloride

Thionyl chloride

4-nitrophenylacetic acid

→

4-nitrophenylacetone

Ausbeute 52.0%

Lösungsmittel

water

t-butyl methyl ether

Dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISTILLATIONThionyl chloride was distilled off under reduced pressure
2. 2
   workup.ADDITIONDichloromethane (3 ml) was added to the azeotropic residue
3. 3
   workup.DISSOLUTIONto dissolve the residue, which
4. 4
   workup.ADDITIONwas added to Solution B dropwise
5. 5
   workup.STIRRINGAfter stirred for 7 hours
6. 6
   Temperaturunder reflux
7. 7
   Temperaturthe reaction solution was cooled to room temperature
8. 8
   workup.ADDITIONpoured into water (10 ml)
9. 9
   SonstigeThe layers were separated
10. 10
    Extraktionthe aqueous layer was extracted with dichloromethane (3 ml)
11. 11
    workup.DISTILLATIONthe solvent was distilled off under reduced pressure
12. 12
    workup.DISTILLATIONAfter the solvent was distilled off
13. 13
    workup.ADDITIONacetic acid (1.7 ml), water (1.1 ml) and concentrated sulfuric acid (0.21 ml) were added
14. 14
    Temperaturwhich was refluxed at an external temperature of 125° C. for 4 hours
15. 15
    workup.STIRRINGwhile stirring vigorously
16. 16
    SonstigeAfter completion of the reaction
17. 17
    Temperaturcooled
18. 18
    Sonstigereturned to room temperature
19. 19
    Extraktionfollowed by extraction
20. 20
    WaschenAfter the organic layer was washed with an aqueous saturated sodium hydrogen carbonate solution (6 ml) twice
21. 21
    workup.DISTILLATIONbrine (6 ml) twice, the solvent was distilled off under reduced pressure
22. 22
    Sonstigethe residue was purified by silica gel column chromatography

Vorschrift

Dichloromethane (3 ml) and ethyl malonate (1.31 g, 8.15 mmol) were added to aluminium chloride (1.10 g, 8.28 mmol) (hereinafter, abbreviated as Solution B). Thionyl chloride (1.58 g, 13.25 mmol) was added to 4-nitrophenylacetic acid (1.00 g, 5.52 mol), followed by stirring at 70-75° C. for 45 minutes. Thionyl chloride was distilled off under reduced pressure, followed by azeotropy with toluene (3 ml) twice. Dichloromethane (3 ml) was added to the azeotropic residue to dissolve the residue, which was added to Solution B dropwise. After stirred for 7 hours under reflux, the reaction solution was cooled to room temperature and poured into water (10 ml). The layers were separated, and the aqueous layer was extracted with dichloromethane (3 ml). The organic layers were combined, and the solvent was distilled off under reduced pressure. After the solvent was distilled off, acetic acid (1.7 ml), water (1.1 ml) and concentrated sulfuric acid (0.21 ml) were added thereto, which was refluxed at an external temperature of 125° C. for 4 hours while stirring vigorously. After completion of the reaction, the mixture was ice-cooled, returned to room temperature, and t-butyl methyl ether (6 ml) and water (6 ml) were added thereto, followed by extraction. After the organic layer was washed with an aqueous saturated sodium hydrogen carbonate solution (6 ml) twice and brine (6 ml) twice, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography to give 4-nitrophenylacetone (0.51 g, 2.87 mmol, 52%).

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