Hexachloroethane → 5-Chloro-4-nitro-1-(oxetan-3-ylmethyl)-1H-pyrazole

Temperature

-78 °C

To a solution of 4-nitro-1-(oxetan-3-ylmethyl)pyrazole (3200 mg, 17.47 mmol) in THF (80 mL) was added LHMDS (1M solution in THF, 22.7 mL, 22.7 mmol) dropwise at −78° C. over a period of 15 min. The resulting mixture was stirred at −78° C. for 30 min. Hexachloroethane (5.38 g, 22.7 mmol.) in THF (20 mL) was added at −78° C. dropwise. The resulting mixture was stirred at −78° C. for another 40 min. The reaction mixture was quenched with aqueous ammonium chloride and extracted with Ethyl acetate (×3). Combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The crude material was purified by column chromatography with 0 to 75% ethyl acetate in heptane as eluent to give 5-chloro-4-nitro-1-(oxetan-3-ylmethyl)-1H-pyrazole (3.60 g, 95%).

1. stirringThe resulting mixture was stirred at −78° C. for another 40 min
2. customThe reaction mixture was quenched with aqueous ammonium chloride
3. extractionextracted with Ethyl acetate (×3)
4. dry with materialCombined organic layers were dried over Na2SO4
5. concentrationconcentrated under reduced pressure
6. customThe crude material was purified by column chromatography with 0 to 75% ethyl acetate in heptane as eluent

ORD record

ord-a0a0abc635744ce39aac9b2e891fcf7d

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08614206B2