Hydrochloric Acid → HCID 178499459, compound

Participants

Reaction Steps

A solution of 3-methyl-5-pyrazoleacetic acid (5.0 g, 35.7 mmol) [see C. Ainsworth, J. Amer. Chem. Soc., 76, 3172 (1954)] in methanol (50 mL) is saturated with HCl gas. The mixture is warmed to reflux for 5 hours, after which the solution is concentrated. The solid residue is taken up in chloroform and washed with 0.5N aqueous sodium bicarbonate, dried over MgSO4, and evaporated to afford 3-methyl-5-pyrazoleacetic acid methyl ester (3.9 g, 70%) sufficiently pure for further use.

Provenance & Evidence