Water → 4-bromomethyl-3,5-dichloro-1-ethyl-1H-pyrazole

Temperature

-30 °C

A solution of 0.82 g (4.2 mmoles) of (3,5-dichloro-1-ethyl-1H-pyrazol-4-yl)methanol dissolved in 50 ml of diethyl ether was cooled to −30° C. Thereto was added 1.3 g (4.8 mmoles) of phosphorus tribromide. The mixture was stirred at room temperature for 12 hours to give rise to a reaction. After confirmation of the completion of the reaction, the reaction mixture was poured into water, followed by extraction with ethyl acetate. The resulting organic layer was washed with water and an aqueous sodium chloride solution and then dried over anhydrous magnesium sulfate. The resulting solution was subjected to vacuum distillation to remove the solvent contained therein, to obtain 0.9 g (yield: 81.8%) of 4-bromomethyl-3,5-dichloro-1-ethyl-1H-pyrazole as a yellow oily substance.

1. customto give rise
2. customto a reaction
3. customAfter confirmation of the completion of the reaction
4. extractionfollowed by extraction with ethyl acetate
5. washThe resulting organic layer was washed with water
6. dry with materialan aqueous sodium chloride solution and then dried over anhydrous magnesium sulfate
7. distillationThe resulting solution was subjected to vacuum distillation
8. customto remove the solvent

ORD record

ord-b6c94891026f4a30870a10e45d8cdf62

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07238689B2