反应详情

温度

-78 °C

To a solution of 4-nitro-1-tetrahydropyran-4-yl-pyrazole (1.32 g; 6.69 mmol) in THF (15 mL) was added dropwise LHMDS (1 mol/L) in THF (2.0 equiv.; 13.4 mmol) at −78° C. The reaction was stirred at −78° C. for 30 minutes before the addition of hexachloroethane (2.4 g, 10 mmol) in THF (5 mL). The reaction was stirred at −78° C. before warming to room temperature. The reaction was diluted with sat. NaCl and extracted with EtOAc (3×). The combined extracts were washed with brine, dried over sodium sulfate, filtered and concentrated. The crude product was purified by flash chromatography to give 5-chloro-4-nitro-1-(tetrahydro-2H-pyran-4-yl)-1H-pyrazole (0.98 g, 63%).

1. temperaturebefore warming to room temperature
2. extractionextracted with EtOAc (3×)
3. washThe combined extracts were washed with brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. customThe crude product was purified by flash chromatography