Water → 4-(bromomethyl)-5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazole

Participants

Reaction Steps

To a solution of 11.5 g (50.0 mmol) of 5-difluoromethoxy-1,4-dimethyl-3-trifluoromethyl-1H-pyrazole in 50 ml of carbon tetrachloride were added 9.8 g (55.0 mmol) of N-bromosuccinimide and 0.41 (2.5 mmol) of α,α′-azobisisobutyronitrile, followed by heating and refluxing under stirring. The reaction solution was externally irradiated with a light for 1 hour. After the completion of the reaction was confirmed, the reaction solution was poured into water and extracted with chloroform. The resulting organic layer was washed with water and saline, successively, and then dried over anhydrous magnesium sulfate. The solvent was removed by evaporation under reduced pressure to obtain 17.8 g (purity: 72.0%, yield: 82.7%) of 4-bromomethyl-5-difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazole.

Provenance & Evidence