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General procedure for the synthesis of 4-amino-1-isopropyl-1H-pyrazole from 1-isopropyl-4-nitro-1H-pyrazole: To a 25 mL round bottom flask was added a methanol solution (4 mL) of 1-isopropyl-4-nitro-1H-pyrazole (200 mg, 1.29 mmol, 1.00 equiv.) and palladium carbon (40 mg). Hydrogen (H2) was passed into the reaction system and the reaction was stirred for 3 hours at room temperature. Upon completion of the reaction, the solid catalyst was removed by filtration and the filtrate was concentrated in vacuum to afford 154 mg (95% yield) of 4-amino-1-isopropyl-1H-pyrazole as a pink oil.

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