Sulfuric Acid → 3-bromo-N-(4-chloro-2-(1-cyclopropylethylcarbamoyl)phenyl)-1-(3-chloropyridin-2-yl)-4,5-dihydro-1H-pyrazole-5-carboxamide

Participants

Reaction Steps

10.0 g of 5-(4-chloro-2-(1-cyclopropylethylcarbamoyl)phenylcarbamoyl)-1-(3-chloropyridin-2-yl)-4,5-dihydro-1H-pyrazol-3-yl2-nitrobenzene sulfonate was dissolved in 30 mL of acetic acid, and after adding 2.4 g of sodium bromide, 1.3 mL of 98 mass % concentrated sulfuric acid was dropwise added at room temperature. After completion of the dropwise addition, heating was carried out at an internal temperature of from 40 to 50° C. for about two hours. After completion of the reaction, the reaction solution was dropwise added into 60 mL of a 8 mass % sodium hydroxide aqueous solution to obtain 8.3 g of the desired product in a crystal form.

Provenance & Evidence