反应详情

A mixture of 1-methyl-4-nitro-1H-pyrazole-3-carboxylic acid methyl ester (500 mg, 2.7 mmol) and 10% palladium on carbon (50 mg) in methanol (25 mL) was subjected to 60 psi pressure of hydrogen gas in a Parr apparatus for 24 h. At this time, the reaction mixture was filtered through a pad of celite and washed with methanol. The filtrate was concentrated in vacuo to afford 4-amino-1-methyl-1H-pyrazole-3-carboxylic acid methyl ester (402 mg, 96%) as an off-white solid: 1H NMR (DMSO-d6, 300 MHz) δ7.10 (s, 1H), 4.65 (broad s, 2H), 3.73 (s, 3H), 3.72 (s, 3H).

1. filtrationAt this time, the reaction mixture was filtered through a pad of celite
2. washwashed with methanol
3. concentrationThe filtrate was concentrated in vacuo