反应详情

A solution of 0.36 g of sodium hydroxide in 15 ml of water is added to a suspension of 1.86 g of ethyl 4,5-dichloro-6-(1-methyl-5-pyrazolylcarbonyl)-1,3-benzodi oxole-2-carboxylate in 35 ml of ethanol and the mixture is stirred at room temperature for 0.5 hour. The reaction mixture is concentrated to remove ethanol and adjusted to pH 1 with aqueous 10% hydrochloric acid. The resultant crystals are collected by filtration, washed successively with water and isopropyl ether and dried to give 1.66 g of 4,5-dichloro-6-(1-methyl-5-pyrazolylcarbonyl)-1,3-benzodioxole-2-carboxylic acid. Yield: 97%

1. concentrationThe reaction mixture is concentrated
2. customto remove ethanol
3. filtrationThe resultant crystals are collected by filtration
4. washwashed successively with water and isopropyl ether
5. customdried