反応 #219230

反応方程式

4-(2,6-difluoro-benzoylamino)-1H-pyrazole-3-carboxylic acid ethyl ester

→

4-(2,6-difluoro-benzoylamino)-1H-pyrazole-3-carboxylic acid

収率 61.7%

溶媒

NaOH MeOH

反応条件

後処理

1. 1
   その他Volatile materials were removed in vacuo, water (300 ml)
2. 2
   workup.ADDITIONadded
3. 3
   ろ過The resultant precipitate was collected by filtration
4. 4
   乾燥dried through azeotrope with toluene

実験手順

A mixture of 4-(2,6-difluoro-benzoylamino)-1H-pyrazole-3-carboxylic acid ethyl ester (10.2 g) in 2 M aqueous NaOH/MeOH (1:1, 250 ml) was stirred at ambient temperature for 14 h. Volatile materials were removed in vacuo, water (300 ml) added and the mixture taken to pH 5 using 1M aqueous HCl. The resultant precipitate was collected by filtration and dried through azeotrope with toluene to afford 4-(2,6-difluoro-benzoylamino)-1H-pyrazole-3-carboxylic acid as a pink solid (5.70 g). (LC/MS: Rt 2.33, [M+H]+267.96).

出典