Acetyl chloride → HCID 117941925, compound

Participants

Reaction Steps

1-(2-bromo-5-chlorophenyl)-3-methyl-1H-pyrazole/1-(2-bromo-5-chlorophenyl)-5-methyl-1H-pyrazole mixture (Intermediate 3, step 1) (1.00 g, 3.68 mmol) was dissolved in THF (6 mL) and cooled to 0° C. i-Propyl magnesium chloride (2.76 mL, 2.0 M in THF, 5.52 mmol) was added dropwise and allowed to warm to RT over 30 min. The reaction was then cooled to −15° C. Acetyl chloride (481 μL, 5.5 mmol) was added and the reaction was warmed to RT for 3 h. The reaction was quenched with HCl (2 N, 4 mL), then extracted with water and EtOAc, washed with brine, and dried over Na2SO4, filtered, and concentrated in vacuo. Purification by normal phase silica gel column chromatography (EtOAc/heptane) provided 1-[4-chloro-2-(3-methyl-pyrazol-1-yl)-phenyl]-ethanone.

Provenance & Evidence