Hydrochloric Acid → methyl 1-(3-chloropyridin-2-yl)-5-hydroxy-3-(hydroxymethyl)-4,5-dihydro-1H-pyrazole-5-carboxylate

Participants

Reaction Steps

A mixture of methyl 4-amino-5-hydroxy-2-oxopent-3-enoate (1.59 g, 10 mmol), 3-chloropyridin-2-ylhydrazine (1.43 g, 10 mmol and HCl (1 g, 10 mmol, 37% solution in water) was stirred in 15 ml of acetonitrile at 25° C. for 20 hours. The solution was concentrated under reduced pressure and the residue was washed with water and isopropanol. This gave 2.13 g (75%) of the product, with a melting point of 111-113° C.

Provenance & Evidence