1-(4-Fluorophenyl)-5-methoxy-1H-indazole → 1-(4-Fluorophenyl)-1H-indazol-5-ol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

1-(4-fluorophenyl)-5-methoxy-1H-indazole (147f, 3.32 g, 13.7 mmol) in CH2Cl2 (40 mL, dried over 4 Å mol sieves). Borontribromide solution (1M in dichloromethane, 35 mL, 35 mmol) was added and the mixture was stirred at 50° C. for 80 min. The reaction mixture was cooled to r.t., diluted with dichloromethane and washed with ice-cold sat. aqueous NaHCO3. Crude title compound crystallised from the organic phase at 8° C. Re-crystallization from methanol-water afforded 1-(4-fluorophenyl)-1H-indazol-5-ol as light grey needles (1.88 g). From the mother liquor was obtained by crystallization (methanol-water) additional title compound (0.7 g). Total yield 2.58 g (82%).

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