4-chloro-1-methyl-1H-pyrazole-3-carbaldehyde → (4-chloro-1-methyl-1H-pyrazol-3-yl)methanol

To a solution of 4-chloro-1-methyl-1H-pyrazole-3-carbaldehyde (10.0 g, 69.2 mmol) in methanol (190 mL) was added sodium borohydride (3.93 g, 104 mmol) at 0° C. The mixture was stirred for 2 hours at room temperature and quenched with water. The solvent was evaporated, water was added, and the mixture was extracted 3 times with ethyl acetate. The combined organic phase was washed with brine and dried over sodium sulfate. After evaporation of the solvent, (4-chloro-1-methyl-1H-pyrazol-3-yl)methanol was obtained (9.04 g, 90% yield) and used in the next step without further purification; 1H NMR (500 MHz, DMSO-d6): δ 3.77 (s, 3H), 4.35 (d, J=5.5 Hz, 2H), 5.03 (t, J=5.5 Hz, 1H), 7.84 (s, 1H).

1. customquenched with water
2. customThe solvent was evaporated
3. additionwater was added
4. extractionthe mixture was extracted 3 times with ethyl acetate
5. washThe combined organic phase was washed with brine
6. dry with materialdried over sodium sulfate
7. customAfter evaporation of the solvent

ORD record

ord-894f08e5df134d73b02bc8c178bb31c7

Source dataset

uspto-grants-2015_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09040538B2