637336-53-9

General procedure for the synthesis of methyl 1-methyl-4-aminopyrazole-3-carboxylate from ethyl 1-methyl-4-nitropyrazole-3-carboxylate: a mixture of methyl 1-methyl-4-nitro-1H-pyrazole-3-carboxylate (500 mg, 2.7 mmol) and 10% palladium carbon (50 mg) in methanol (25 mL) was placed in a Parr reactor at 60 psi of hydrogen pressure for 24 hours. Upon completion of the reaction, the mixture was filtered through a diatomaceous earth pad and washed with methanol. The filtrate was concentrated under reduced pressure to afford methyl 1-methyl-4-amino-1H-pyrazole-3-carboxylate (402 mg, 96% yield) as an off-white solid.

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