Hydrazine hydrate (1:1) → 4-Isopropyl-1H-pyrazole-3,5-diamine

Temperature

80 °C

Hydrazine monohydrate (2.05 mL, 42 mmol) was added to a solution of the product from Example 112A (1.16 g, 10.7 mmol) in EtOH (15 mL). The reaction flask was evacuated and purged with nitrogen (3 cycles), then heated at 80° C. for 22 hours. The yellow solution was cooled to room temperature and concentrated under vacuum. Toluene (8 mL) was added to the residue, and the mixture was concentrated under vacuum to remove excess hydrazine (repeated twice more) to provide the title compound. MS (ESI) m/z 141 (M+H)+.

1. customThe reaction flask was evacuated
2. custompurged with nitrogen (3 cycles)
3. temperatureThe yellow solution was cooled to room temperature
4. concentrationconcentrated under vacuum
5. additionToluene (8 mL) was added to the residue
6. concentrationthe mixture was concentrated under vacuum
7. customto remove excess hydrazine (

ORD record

ord-a62d8b2e19bd4e3d8b80a5662923c270

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08609669B2