Реакция #657309

Уравнение реакции

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

Выход 56.0%

Растворители

DMF

water

Условия реакции

Обработка

1. 1
   Экстракцияextracted with diethyl ether
2. 2
   СушкаThe organic layer was dried over anhydrous sodium sulphate
3. 3
   Концентрированиеconcentrated
4. 4
   Другоеto get the crude product
5. 5
   ДругоеPurification by column chromatography over silica gel (eluent 5-10% ethyl acetate in petrol ether)

Методика

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.

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