[Cl:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][N:6]=[C:5]2[CH2:11][OH:12]>C(OCC)(=O)C.[O-2].[O-2].[Mn+4]>[Cl:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][N:6]=[C:5]2[CH:11]=[O:12]A solution of (5-chloro-1H-indazol-3-yl)methanol (0.208 g, 1.14 mmol) in ethyl acetate (10 mL) was added with manganese dioxide (0.991 g, 11.4 mmol), and the mixture was stirred overnight at room temperature. The reaction mixture was filtered through Celite, then the filtrate was concentrated, and the resulting residue was purified by silica gel column chromatography (chloroform/methanol) to obtain 5-chloro-1H-indazole-3-carbaldehyde (0.106 g, 51%).
Wird geladen…