Potassium Carbonate → 1-(propan-2-yl)-1H-pyrazol-3-amine

Temperatur

45 °C

2-Chloroacrylonitrile (3.41 mL, 42.59 mmol) was added at RT to a stirring solution of N-isopropylhydrazine hydrochloride (4.71 g, 42.6 mmol), potassium carbonate (11.8 g, 85.2 mmol) in water (50 mL). The reaction was warmed to 45° C. for 4 hours before cooling back to RT. The aqueous layer was then extracted with ethyl acetate (5×30 mL) and the combined organic layers were dried (MgSO4), treated with activated charcoal, filtered and evaporated. The residue was purified by chromatography, eluting with 67%-100% ethyl acetate in hexanes, to afford the title compound (3.08 g, 58%) as a 6:1 mixture of authentic product to regioisomeric product as an oil. The material was used without further purification.

1. temperaturebefore cooling back to RT
2. extractionThe aqueous layer was then extracted with ethyl acetate (5×30 mL)
3. dry with materialthe combined organic layers were dried (MgSO4)
4. additiontreated with activated charcoal
5. filtrationfiltered
6. customevaporated
7. customThe residue was purified by chromatography
8. washeluting with 67%-100% ethyl acetate in hexanes

ORD-Eintrag

ord-3d1941a623324da78a0d203e0cbd8d49

Quelldatensatz

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07745475B2