Reacción #710491

Ecuación de reacción

water

sodium borohydride

ethyl (3,5-dichloropyridin-2-yl)(difluoro)acetate

HCl

→

2-(3,5-dichloropyridin-2-yl)-2,2-difluoroethanol

Disolventes

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   ExtracciónThe aequeous phase was extracted three times by 300 mL of ethyl acetate
2. 2
   Lavadothe organic phase was successively washed with brine, water
3. 3
   Secadodried over magnesium sulfate
4. 4
   OtroAfter evaporation of the solvent under vacuum 8.5 g of yellow oil
5. 5
   Otrowere obtained
6. 6
   FiltraciónAfter trituration in diisopropyl ether and filtration 6.8 g (80%) of 2-(3,5-dichloropyridin-2-yl)-2,2-difluoroethanol (Int-9)
7. 7
   Otrowere obtained as a white solid
8. 8
   OtroMp (melting point)=56° C. (M+1)=228

Procedimiento

To a solution of 10 g (37 mmol) of ethyl (3,5-dichloropyridin-2-yl)(difluoro)acetate (Int-7) in 60 mL of ethanol, were added portionwise at 0° C., 1.05 g (27.7 mmol) of sodium borohydride. The reaction mixture was stirred below 10° C. for 2 hours. 30 mL of 1 N HCl were then slowly added followed by 500 mL of water. The aequeous phase was extracted three times by 300 mL of ethyl acetate and the organic phase was successively washed with brine, water and dried over magnesium sulfate. After evaporation of the solvent under vacuum 8.5 g of yellow oil were obtained. After trituration in diisopropyl ether and filtration 6.8 g (80%) of 2-(3,5-dichloropyridin-2-yl)-2,2-difluoroethanol (Int-9) were obtained as a white solid. Mp (melting point)=56° C. (M+1)=228. 19F-NMR (235 MHz, CDCl3) δ (ppm): −105.85 (CF2).

Fuente