反应详情

A suspension of 7-nitro-2,3-dihydro-1H-imidazo[1,2-b]pyrazole (97 g) in a mixed solvent of sulfuric acid (34 ml) and water (2000 ml) was treated with 10% palladium on carbon (10 g) under a hydrogen atmosphere at room temperature for 4 days. After the catalyst was filtered off, the filtrate was concentrated in vacuo. The residue was triturated with methanol and dried in vacuo to give 7-amino-2,3-dihydro-1H-imidazo[1,2-b]pyrazole sulfuric acid salt (90.2 g) as a solid.

1. filtrationAfter the catalyst was filtered off
2. concentrationthe filtrate was concentrated in vacuo
3. customThe residue was triturated with methanol
4. customdried in vacuo