Nitric Acid → (2,3-Difluoro-5-nitrophenyl)acetic acid
反応式
[F:1][C:2]1[C:7]([F:8])=[CH:6][CH:5]=[CH:4][C:3]=1[CH2:9][C:10]([OH:12])=[O:11].[N+:13]([O-])([OH:15])=[O:14]>S(=O)(=O)(O)O>[F:1][C:2]1[C:7]([F:8])=[CH:6][C:5]([N+:13]([O-:15])=[O:14])=[CH:4][C:3]=1[CH2:9][C:10]([OH:12])=[O:11]参加物
4
反応条件
- 温度
- -10 °C
実験手順
(2,3-Difluoro-phenyl)-acetic acid (11, 5 g, 0.0290 mol) is dissolved in concentrated sulfuric acid (20 ml) and the resulting solution cooled to −10° C. with vigorous stirring. A solution of nitric acid (1.88 ml, 69.3%, 0.0290 mol) and sulfuric acid (2 ml) is added dropwise at a rate such that the temperature remains below −5° C. The thickened slurry is stirred for 15 minutes and then poured on ice. The resulting white precipitate is filtered and dried under vacuum (6.3 g, 99%) and consists of a 50/50 mixture of 5 and 6-NO2 regioisomers suitable for use directly in the next step.