Ethyl bromoacetate → (4-Chloro-5-methyl-3-trifluoromethyl-pyrazol-1-yl)-acetic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-chloro-5-methyl-3-(trifluoromethyl)pyrazole (15 g, 81.3 mmol) in DMF (82 mL) was added ethyl 2-bromoacetate (13.6 g, 81.3 mmol) and potassium carbonate (12.4 g, 89.4 mmol). The mixture was heated at 55° C. for 10 hours with stirring. After cooling to room temperature, the reaction mixture was diluted with water (100 mL) and extracted with ethyl acetate (3×150 mL). The combined organic layers were washed with brine, dried (Na2SO4), filtered, and concentrated in vacuo. The crude residue was purified by flash chromatography (SiO2, 0-30% ethyl acetate in hexanes) to afford the desired product (18.5 g, 68.4 mmol, 84%).

Provenance & Evidence