2-(3-nitro-1H-pyrazol-1-yl)ethanol → 2-(3-Amino-1H-pyrazol-1-yl)ethan-1-ol

A solution 2-(3-nitro-pyrazol-1-yl)-ethanol (3.46 g, 22.02 mmol) in ethanol (40 mL) was placed in a Parr shaker bottle and treated with 10% palladium on carbon (350 mg). The bottle was then put on the Parr shaker and charged with hydrogen to 50 psi and let shake for 1 h. After this time, the reaction mixture was filtered through celite and the celite washed with ethanol. The filtrate was then concentrated in vacuo and azeotroped with acetonitrile and then chloroform to afford 2-(3-amino-pyrazol-1-yl)-ethanol (3.02 g, >quant.) as a light yellow viscous oil: 1H NMR (300 MHz, DMSO-d6 δ ppm 7.26 (d, J=1.83 Hz, 1H), 5.34 (d, J=2.20 Hz, 1H), 4.76 (t, J=5.31 Hz, 1H), 4.50 (s, 2H), 3.78-3.88 (m, 2H), 3.62 (q, J=5.74 Hz, 2H).

1. filtrationAfter this time, the reaction mixture was filtered through celite
2. washthe celite washed with ethanol
3. concentrationThe filtrate was then concentrated in vacuo
4. customazeotroped with acetonitrile

ORD record

ord-09e9b1cdff5244bc9f16249fa962df3b

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08697705B2