Ammonium Chloride → 3-bromo-5-(2-chloro-4-fluorophenyl)-alpha-(2,4-difluorophenyl)-1-methyl-1H-pyrazole-4-methanol

Temperature

-78 °C

To a mixture of 3-bromo-5-(2-chloro-4-fluorophenyl)-4-iodo-1-methyl-1H-pyrazole (i.e. the product of Step D) (250 mg, 0.602 mmol) in tetrahydrofuran (3 mL) at −78° C. was added dropwise n-butyllithium (2.5 M solution in hexanes, 0.36 mL, 0.90 mmol). Stirring was continued for 1 h at −78 to −40° C., and then the reaction mixture was cooled to −78° C. and 2,4-difluorobenzaldehyde (103 mg, 0.72 mmol) in tetrahydrofuran (2 mL) was added dropwise. The reaction mixture was allowed to warm to room temperature and stirred for 3 h, and then saturated aqueous ammonium chloride solution was added and the mixture was extracted with ethyl acetate (2×20 mL). The combined organic layers were washed with water and saturated aqueous sodium chloride solution, dried over sodium sulfate and concentrated under reduced pressure. The resulting material was purified by silica gel chromatography (10 to 50% gradient of ethyl acetate in hexanes as eluant) to provide the title compound, a compound of the present invention, as an off-white solid (35 mg).

1. temperatureto warm to room temperature
2. stirringstirred for 3 h
3. extractionthe mixture was extracted with ethyl acetate (2×20 mL)
4. washThe combined organic layers were washed with water and saturated aqueous sodium chloride solution
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe resulting material was purified by silica gel chromatography (10 to 50% gradient of ethyl acetate in hexanes as eluant)

ORD record

ord-5c71a5a20b5a49c6b627d6b607036a31

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09131693B2