1-Amino-2-propanol → HCID 13007219, compound

A mixture of 3,5-dibromo-1-ethyl-4-nitro-1H-pyrazole (3) (20.0 g; 66.9 mmol), EtOH (100 ml) and 1-amino-2-propanol (25.1 g, 334.2 mmol) was refluxed for 15 hours. The reaction medium was concentrated to the maximum under reduced pressure and the excess 1-amino-2-propanol was then distilled off under vacuum. The oil obtained was suspended in DCM (100 ml) and water (100 ml). The aqueous phase was washed with DCM (100 ml). The combined organic phases were washed with water (50 ml) and were then dried over NaSO4. After evaporating off the solvent under reduced pressure, a brown solid was obtained (19.1 g), which was purified by chromatography on silica gel (eluent: EtOAc/hexane). After recrystallization of the solid from an EtOAc/hexane mixture (13 ml/20 ml), the 1-(5-bromo-2-ethyl-4-nitro-2H-pyrazol-3-ylamino)propan-2-ol was obtained in the form of a yellow solid (7.1 g, 36%).

1. temperaturewas refluxed for 15 hours
2. concentrationThe reaction medium was concentrated to the maximum under reduced pressure
3. distillationthe excess 1-amino-2-propanol was then distilled off under vacuum
4. customThe oil obtained
5. washThe aqueous phase was washed with DCM (100 ml)
6. washThe combined organic phases were washed with water (50 ml)
7. dry with materialwere then dried over NaSO4
8. customAfter evaporating off the solvent under reduced pressure
9. customa brown solid was obtained (19.1 g), which
10. customwas purified by chromatography on silica gel (eluent: EtOAc/hexane)
11. customAfter recrystallization of the solid from an EtOAc/hexane mixture (13 ml/20 ml)

ORD record

ord-2468d705ff904e18b7d83c583d3b8c62

Source dataset

uspto-grants-2007_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07300469B2