Methyl 6-amino-5-nitropyridine-2-carboxylate → Methyl 5,6-diamino-2-pyridinecarboxylate

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Reaction Steps

Methyl ester 3 (3.5 g, 18.0 mmol) was dissolved in methanol (300 mL) and EtOAc (300 mL) and the solution was degassed with Ar. After the addition of Pd/C (10 wt %, 0.7 g) the reaction mixture was stirred for 4 h under a hydrogen atmosphere. Filtration through a pad of Celite with EtOAc, evaporation of the solvent and purification by flash chromatography (EtOAc/MeOH 15:1) yielded 2.4 g (79%) of 4 as a deep red powder. Data of 4: Rf 0.42 (EtOAc/MeOH 15:1). 1H NMR (300 MHz, DMSO-d6): δ 3.68 (s, 3H), 5.51 (brs, 2H), 5.78 (brs, 2H), 6.67 (d, J1) 7.7 Hz, 1H), 7.21 (d, J1) 7.7 Hz, 1H). 13C NMR (75 MHz, DMSO-d6): δ 51.88, 116.32, 117.98, 132.40, 135.09, 147.93, 166.30. MS (ESI): m/z (rel intensity) 168 (100).

Provenance & Evidence