5-Fluoro-2-methyl-4-nitroaniline → 6-Fluoro-5-nitro-1H-indazole

Participants

Reaction Steps

The product of Step (b) (1.22 g, 7.17 mmol, 1.0 equiv) was dissolved In AcOH (62 mL). NaNO2 (0.495 g, 7.17 mmol, 1.0 equiv) was dissolved in H2O (1.5 mL) and added all at once via pipet. The reaction was warmed to room temperature and stirred for 28 hours. The reaction mixture was concentrated en vacuo to provide an orange solid, which was dried azeotropically several times with hexanes. The residue was purified by flash chromatography (linear gradient 20→60% EtOAc/hexanes) to afford 550 mg (43%) of the title compound. MS (ES+) m/e 182 [M+H].

Provenance & Evidence