Hydrochloric Acid → 5-bromo-3-(trifluoromethyl)-1H-pyrazole-1-acetic acid
反応式
[Br:1][C:2]1[N:6]([CH2:7][C:8]([O:10]CC)=[O:9])[N:5]=[C:4]([C:13]([F:16])([F:15])[F:14])[CH:3]=1.[OH-].[Na+].Cl>O1CCCC1>[Br:1][C:2]1[N:6]([CH2:7][C:8]([OH:10])=[O:9])[N:5]=[C:4]([C:13]([F:16])([F:14])[F:15])[CH:3]=1参加物
5
実験手順
A solution of ethyl 5-bromo-3-(trifluoromethyl)-1H-pyrazole-1-acetate (i.e. the product of Example 11, Step C) (2.84 g, 9.4 mmol) in tetrahydrofuran (10 mL) was treated with a 50 wt. % aqueous sodium hydroxide solution (1.0 mL). The reaction mixture was stirred at room temperature for 2 h. The reaction mixture was treated with concentrated aqueous hydrochloric acid to lower the pH to 1 and then extracted with ethyl acetate. The extract was dried (MgSO4) and concentrated under pressure to give 2.26 g of the title compound as a light brown solid. Recrystallization from 1-chlorobutane (20 mL) gave 0.68 g of the title compound as lustrous light pink plates.