Reacción #67606

Ecuación de reacción

potassium carbonate

3,4-dihydroxy benzaldehyde

potassium carbonate

potassium carbonate

chlorodifluoromethane

→

4-difluoromethoxy-3-hydroxy benzaldehyde

Rendimiento 25.0%

Disolventes

water

N,N-dimethylformamide

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrofor about 30 minutes
2. 2
   Otroat about 80-85° C
3. 3
   workup.STIRRINGstirred for about one and half hours
4. 4
   workup.STIRRINGstirred for about one and half hours
5. 5
   workup.STIRRINGThe reaction mixture was then stirred for about 5-6 hours at an ambient temperature
6. 6
   FiltraciónThe reaction mixture was filtered
7. 7
   Concentraciónthe filtrate was concentrated under reduced pressure
8. 8
   OtroThe residue obtained
9. 9
   Extracciónextracted with ethyl acetate (3×200 mL)
10. 10
    SecadoThe combined organic layer was dried over anhydrous sodium sulphate
11. 11
    Concentraciónconcentrated under reduced pressure
12. 12
    OtroThe crude product obtained
13. 13
    Otrowas purified through silica gel column

Procedimiento

To a well stirred suspension of 3,4-dihydroxy benzaldehyde (100 gm) and anhydrous potassium carbonate (120 gm) in dry N,N-dimethylformamide (1.0 lit) was passed chlorodifluoromethane gas for about 30 minutes at about 80-85° C. After an hour another lot of anhydrous potassium carbonate (25.0 gm) was added and stirred for about one and half hours. The third lot of anhydrous potassium carbonate (25.0 gm) was added and stirred for about one and half hours. The reaction mixture was then stirred for about 5-6 hours at an ambient temperature. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure. The residue obtained was diluted with water (500 mL) and extracted with ethyl acetate (3×200 mL). The combined organic layer was dried over anhydrous sodium sulphate and concentrated under reduced pressure. The crude product obtained was purified through silica gel column to give 4-difluoromethoxy-3-hydroxy benzaldehyde.

Fuente