tert-Butyl 5-Nitro-1H-indazole-1-carboxylate → 1,1-Dimethylethyl 5-amino-1H-indazole-1-carboxylate

Participants

Reaction Steps

Palladium on carbon (780 mg) was placed under an inert atmosphere and suspended in EtOH (15 mL). A solution of give 5-nitroindazole-1-carboxylic acid tert-butyl ester (7.78 g, 29.5) in EtOH (100 mL) and EtOAc (100 mL) was added. The reaction mixture was placed under H2 atmosphere (1 Atm pressure) and stirred overnight. The resulting mixture was filtered through a pad of Celite®. The filtrate was concentrated under reduced pressure to get a greenish foamy solid. The crude product was dissolved in CH2Cl2 and purified by Biotage Flash 40M (gradient from 30% to 50% EtOAc/hex) to give the title compound (6.55 g, 95%) as a white solid: TLC (50% EtOAc/hex), Rf=0.41; ES-LCMS (rel abundance) m/z 234 (MH+, 66%).

Provenance & Evidence