Reaktion #86851

Reaktionsgleichung

(Z)-ethyl 2-amino-2-(hydroxyimino)acetate

N,N-diisopropylethylamine

2,5-difluorophenylacetic acid

thionyl chloride

→

2-(2,5-difluorophenyl)acetyl chloride

(Z)-ethyl 2-amino-2-(2-(2,5-difluorophenyl)acetoxyimino)acetate

Ausbeute 89.3%

Lösungsmittel

dichloromethane

chloroform

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturby heating overnight
2. 2
   SonstigeAfter evaporation of the solvent
3. 3
   workup.DISSOLUTIONthe excess of the thionyl chloride under reduced pressure, the residue was dissolved in dried dichloromethane (10 mL)
4. 4
   workup.STIRRINGThe mixture was stirred at room temperature for 23 h
5. 5
   FiltrationThe white precipitate is filtered off
6. 6
   Waschenwashed with dichloromethane
7. 7
   Sonstigedried under reduced pressure

Vorschrift

2-(2,5-difluorophenyl)acetyl chloride was prepared by heating overnight a suspension of 2,5-difluorophenylacetic acid (0.865 g; 3.67 mmol) and thionyl chloride (1.34 mL; 18.15 mmol) in chloroform (30 mL) at 80° C. After evaporation of the solvent and the excess of the thionyl chloride under reduced pressure, the residue was dissolved in dried dichloromethane (10 mL). This solution was added to a suspension of (Z)-ethyl 2-amino-2-(hydroxyimino)acetate (0.500 g; 3.67 mmol) and N,N-diisopropylethylamine (1.03 mL; 5.87 mmol) in dry dichloromethane (20 mL) cooled at −10° C. and stirred for 10 minutes. The mixture was stirred at room temperature for 23 h and poured into a mixture of ice/water. The white precipitate is filtered off and washed with dichloromethane and dried under reduced pressure to afford 0.469 g (45%) of (Z)-ethyl 2-amino-2-(2-(2,5-difluorophenyl)acetoxyimino)acetate as a white solid.

Quelle