3,5-Dimethylpyrazole → HCID 12926677, compound

Temperature

-78 °C

A suspension of 3,5-dimethylpyrazole (3.9 g, 40.7 mmol) and sodium hydride (60% in mineral oil, 1.7 g) in dichloromethane (50 mL) was added dropwise to a cooled (−78° C.) solution of 4,6-dichloro-2-methanesulfonyl-pyrimidine (10 g, 38.7 mmol) in dichloromethane (200 mL). The mixture was stirred at −78° C. for one hour. The reaction was carefully quenched at the same temperature by addition of water (150 mL). The mixture was allowed to warm to room-temperature. Brine (150 mL) was added and the phases were separated. The aqueous phase was extracted with dichloromethane (4×200 mL). The combined organic layers were washed with brine, dried over sodium sulphate, filtrated and concentrated in vacuo. The crude product was purified by flash chromatography (ethyl acetate/heptane as eluent) to give 4,6-dichloro-2-(3,5-dimethyl-pyrazol-1-yl)-pyrimidine (5.5 g, 59%) as a white crystalline compound.

1. additionwas added dropwise to
2. customThe reaction was carefully quenched at the same temperature by addition of water (150 mL)
3. temperatureto warm to room-temperature
4. additionBrine (150 mL) was added
5. customthe phases were separated
6. extractionThe aqueous phase was extracted with dichloromethane (4×200 mL)
7. washThe combined organic layers were washed with brine
8. dry with materialdried over sodium sulphate
9. filtrationfiltrated
10. concentrationconcentrated in vacuo
11. customThe crude product was purified by flash chromatography (ethyl acetate/heptane as eluent)

ORD record

ord-2bd0d8372f0842048a4f17ac515aaa83

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08618099B2