Hydrochloric Acid → 3-bromo-6-nitro-1H-indazole

Participants

Reaction Conditions

Reaction Steps

A mixture of NaOH (2.0 g, 50 mmol) in H2O (60 mL) was added 6-nitroindazole (2.0 g, 12 mmol) and the suspension heated until a red solution formed. The mixture was placed in an ice-water bath for 15 minutes after which pyridinium tribromide (4.7 g, 15 mmol) in MeOH (15 mL) was added. The mixture was stirred at 0° C. for 5 hours after which the pH was adjusted to 7 with diluted HCl. The mixture was extracted with ethyl acetate, and the combined organic layer washed with H2O and concentrated under reduced pressure. The residue was purified by flash chromatography to provide the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 7.84 (m, 1H), 8.02 (m, 1H), 8.50 (m, 1H), 14.16 (s, 1H); MS (DCI/NH3) m/z 243[M+H]+.

Provenance & Evidence