tert-butyl 4-(5-{[(4-nitro-1-phenyl-1H-pyrazol-3-yl)amino]carbonyl}pyridin-2-yl)piperazine-1-carboxylate → tert-butyl 4-(5-{[(4-amino-1-phenyl-1H-pyrazol-3-yl)amino]carbonyl}pyridin-2-yl)piperazine-1-carboxylate

Participants

Reaction Steps

A solution of tert-butyl 4-(5-{[(4-nitro-1-phenyl-1H-pyrazol-3-yl)amino]carbonyl}pyridin-2-yl)piperazine-1-carboxylate (50 mg, 0.1 mmol) in methanol (10 mL) was degassed with nitrogen and treated with catalytic platinum(IV) oxide (25 mg). The solution was then placed under a hydrogen atmosphere with stirring for 20 minutes. The reaction was degassed with nitrogen, filtered through celite and evaporated to dryness. Purification by flash chromatography (0-4% methanol/methylene chloride) gave tert-butyl 4-(5-{[(4-amino-1-phenyl-1H-pyrazol-3-yl)amino]carbonyl}pyridin-2-yl)piperazine-1-carboxylate as a light yellow solid. 1H NMR (CDCl3) δ 8.78 (d, J=2.35, 1H), 8.13 (dd, J=9.01, 2.64 Hz, 1H), 7.78 (s, 1H), 7.64 (d, J=8.8 Hz, 2H), 7.42, (t, J=7.33 Hz, 2H), 7.22 (t, J=7.34, 1H), 6.88 (d, J=9.09 Hz, 1H), 3.71 (t, J=5.28 Hz, 2H), 3.54 (bs, 2H), 1.48 (s, 9H); ESIMS calcd 464.2 (M++H), found 464.2 (M++H).

Provenance & Evidence