Reacción #657309

Ecuación de reacción

3-(4-fluorophenyl)-1H-pyrazol-5-ol

K2CO3

2,2-difluoropropane-1,3-diyl dimethanesulfonate

→

6,6-difluoro-2-(4-fluorophenyl)-6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine

Rendimiento 56.0%

Disolventes

DMF

water

Condiciones de reacción

Tratamiento posterior

1. 1
   Extracciónextracted with diethyl ether
2. 2
   SecadoThe organic layer was dried over anhydrous sodium sulphate
3. 3
   Concentraciónconcentrated
4. 4
   Otroto get the crude product
5. 5
   OtroPurification by column chromatography over silica gel (eluent 5-10% ethyl acetate in petrol ether)

Procedimiento

To a solution of 3-(4-fluorophenyl)-1H-pyrazol-5-ol (4 g, 22.47 mmol) in DMF (30 mL) was added K2CO3 (12.4 g, 89.88 mmol) and 2,2-difluoropropane-1,3-diyl dimethanesulfonate (9 g, 33.7 mmol) at room temperature and then stirred for 16 h at 60° C. The progress of the reaction was monitored by TLC. Thereafter, the reaction mixture was diluted with cold water and extracted with diethyl ether. The organic layer was dried over anhydrous sodium sulphate and concentrated to get the crude product. Purification by column chromatography over silica gel (eluent 5-10% ethyl acetate in petrol ether) yielded 6,6-difluoro-2-(4-fluorophenyl)-6,7-dihydro-5H-pyrazolo[5,1-b][1,3]oxazine (3.2 g, 56%) as an off-white solid.

Fuente