HCID 15278603, compound → HCID 135749814, compound

Participants

Reaction Steps

To a suspension of 1-(2,6-dichloro-4-trifluoromethylphenyl)-6-aminoindazole [Compound No. 47] (10 g) in 50% sulfuric acid (30 g), a solution of sodium nitrite (3 g) in water (10 g) was added dropwise while cooling with ice, and the resultant mixture was stirred. After 1 hour, the mixture was added dropwise for 1 hour to 10% sulfuric acid heated at 100° C. to 110° C., and the resultant mixture was refluxed for 30 minutes. After completion of the reaction, the reaction mixture was cooled and extracted with ethyl acetate. The extract was dried over magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography with hexaneethyl acetate (4:1) to give 1-(2,6-dichloro-4-trifluoromethylphenyl)-6-hydroxyindazole (6 g).

Provenance & Evidence