Sulfuric Acid → 1H-Pyrazole, 4,5-diamine-1-methyl-, sulfate (1:1)

Participants

Reaction Steps

To a suspension of 5-amino-1-methyl-4-nitrosopyrazole (117 g) were added sulfuric acid (91 g) and 10% palladium on carbon (58 g) The mixture was hydrogenated under balloon pressure for 10 hours. The reaction mixture was filtered, and the filtrate was concentrated in vacuo. To the concentrate was added isopropyl alcohol (2.3 L), and the mixture was stirred for 1 hour. The precipitated solid was collected by filtration and dried to give 4,5-diamino-1-methylpyrazole sulfuric acid salt (158 g).

Provenance & Evidence