Di-tert-butyl dicarbonate → tert-Butyl 5-amino-3-methyl-1H-indazole-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

tert-Butyl 3-methyl-5-nitro-1H-indazole-1-carboxylate. To a solution of 3-methyl-5-nitro-1H-indazole (0.95 g, 5.36 mmol) in ethanol (12 mL) was added di-tert-butyl dicarbonate (1.755 g, 8.04 mmol). The reaction was stirred at 50° C. for 5 h. The reaction mixture was cooled down to room temperature and the solvent was removed under reduced pressure. The crude was diluted with ethyl acetate (150 mL), washed with saturated sodium bicarbonate (100 mL), and brine (100 mL). The organic layer was dried over magnesium sulfate, filtered and concentrated down to give the title compound as an off-white solid, which was used in the next step without further purification. MS (ESI) m/z 278.4 [M+1]+.

Provenance & Evidence