Hydrogen Bromide → 6-Bromo-1-(3-fluoro-4-hydroxyphenyl)-1H-indazol-4-ol

Participants

Reaction Conditions

Reaction Steps

48% Hydrobromic acid (10 mL) was added to 6-bromo-1-{3-fluoro-4-[(phenylmethyl)oxy]phenyl}-4-(methyloxy)-1H-indazole (D9) (1.16 g, 2.71 mmol) and the mixture heated at 130° C. for 3 hours. After cooling to room temperature, the mixture was diluted with ethyl acetate and water. The pH was adjusted to 7 by the addition of 2M aqueous sodium hydroxide solution. After separation of the organic layer, the aqueous phase was re-extracted with ethyl acetate. The combined organic layers were dried over magnesium sulphate, filtered and concentrated. The crude product was purified by silica gel chromatography eluting with 5-100% ethyl acetate in hexane. The product was further purified by MDAP to yield the title compound (E5) (170 mg).

Provenance & Evidence