Ammonium Chloride → 5-Chloro-1-isopropyl-1H-pyrazol-4-amine

Temperature

80 °C

To a suspension of 5-chloro-1-isopropyl-4-nitro-1H-pyrazole (1 equiv) and iron dust (3 equiv) in EtOH (0.26 M) was added ammonium chloride (3 equiv). The mixture was heated to 80° C. for 20 h then cooled to room temperature. The reaction was quenched with solid sodium bicarbonate and treated with ethyl acetate (0.09 M) with continuous stirring. The mixture was filtered and the filter cake was rinsed with ethyl acetate. The combined filtrate was dried over sodium sulfate and concentrated under reduced pressure. The crude product was purified by silica gel chromatography (1.5% MeOH in DCM) to provide the desired product (76% yield) as a brown oil. MS (ESI) m/z 160.1 [M+H]+.

1. temperaturethen cooled to room temperature
2. customThe reaction was quenched with solid sodium bicarbonate
3. additiontreated with ethyl acetate (0.09 M) with continuous stirring
4. filtrationThe mixture was filtered
5. washthe filter cake was rinsed with ethyl acetate
6. dry with materialThe combined filtrate was dried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe crude product was purified by silica gel chromatography (1.5% MeOH in DCM)

ORD record

ord-f8dece81f7534d85bec3b5fe082e7622

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09428509B2