Citric Acid → HCID 66643735, Verbindung

Reaktionsgleichung

[CH3:1][O:2][C:3]([C:5]1[N:6]([CH3:26])[N:7]=[C:8]([O:10][CH2:11][C:12]2[C:13]([C:19]3[CH:24]=[CH:23][C:22]([F:25])=[CH:21][CH:20]=3)=[N:14][O:15][C:16]=2[CH:17]=[O:18])[CH:9]=1)=[O:4].[BH4-].[Na+].C(O)(=O)CC(CC(O)=O)(C(O)=O)O>CO>[CH3:1][O:2][C:3]([C:5]1[N:6]([CH3:26])[N:7]=[C:8]([O:10][CH2:11][C:12]2[C:13]([C:19]3[CH:20]=[CH:21][C:22]([F:25])=[CH:23][CH:24]=3)=[N:14][O:15][C:16]=2[CH2:17][OH:18])[CH:9]=1)=[O:4]

Komponenten

Versuchsvorschrift

A solution of 5-[3-(4-fluoro-phenyl)-5-formyl-isoxazol-4-ylmethoxy]-2-methyl-2H-pyrazole-3-carboxylic acid methyl ester (720 mg, 2.0 mmol) and sodium borohydride (158 mg, 4.0 mmol) in methanol (36 mL) were stirred for 1 h at room temperature. Addition of 10% aqueous citric acid (100 mL) was followed by extraction with ethyl acetate. The combined organic extracts were washed with brine, dried over sodium sulfate, filtered and evaporated. Purification by chromatography (silica, heptane:ethyl acetate=4:1 to 1:1) afforded the title compound (510 mg, 70%) as a white solid. MS: m/e=420.3 [M+OAc]−.