84407-13-6

2-(3-Amino-1H-pyrazol-1-yl)ethanol is a reagent in the preparation of pyrazolo pyrimidines with CK2 kinase inhibitory activity.

General procedure for the synthesis of 2-(4-amino-1H-pyrazol-1-yl)ethanol from 3-nitro-1H-pyrazol-1-ethanol: 2-(3-nitro-1H-pyrazol-1-yl)ethanol (0.187 g, 1.19 mmol) was dissolved in ethanol (6 mL) and 10% palladium/carbon catalyst (20 mg) was added under argon protection. The reaction mixture was stirred overnight at room temperature and under hydrogen atmosphere (using a hydrogen balloon). Upon completion of the reaction, the insoluble material was removed by filtration through a diatomaceous earth pad and washed with ethanol. The filtrate and washings were combined and concentrated under reduced pressure to remove the solvent to give the target product 2-(4-amino-1H-pyrazol-1-yl)ethanol (light brown tar-like substance, 0.151 g, 1.18 mmol, 99% yield).

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