methyl 3-chloro-1-(pyridin-3-yl)-1H-pyrazole-5-carboxylate → 3-Chloro-1-(pyridine-3-yl)-1H-pyrazole-5-carboxylic acid hydrochloride

Methyl 3-chloro-1-(pyridin-3-yl)-1H-pyrazole-5-carboxylate (1.5 g, 6.0 mmol) was stirred in concentrated hydrochloric acid (25 mL). The reaction mixture was heated at reflux to afford a yellow solution. After heating overnight a solid had precipitated, and LCMS analysis of the mixture indicated that the reaction was complete. The mixture was allowed to cool to room temperature and dioxane (50 mL) was added. The mixture was concentrated to dryness. acetonitrile (50 mL) was added and the resulting mixture was concentrated. The residue was vacuum dried at 40° C. to afford the desired product as a yellow solid (1.6 g, 97%).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux
3. customto afford a yellow solution
4. temperatureAfter heating overnight a solid
5. customhad precipitated
6. additiondioxane (50 mL) was added
7. concentrationThe mixture was concentrated to dryness
8. additionacetonitrile (50 mL) was added
9. concentrationthe resulting mixture was concentrated
10. customdried at 40° C.

ORD record

ord-b8b6ddcc60964691a97379cc1b18194b

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09255083B2