Water → 5-methoxy-1,3-dimethyl-1H-pyrazole-4-carboxylic acid

Participants

Reaction Steps

2.5 g (0.0162 mole) of 1,3-dimethyl-5-methoxy-4-pyrazole carboxaldehyde (prepared as described in Khim. Farm. Zh, 4, 19 (1970) [CA, 73, 3844 w, (1970)] was dissolved in a solution containing 50 ml of water, 2 ml of acetic acid and 0.6 ml of acetone. 2.56 g (0.0162 mole) of potassium permanganate was added in several portions. The reaction was stirred for 3 hours before decomposing the excess potassium permanganate with 3 ml of methanol and then made alkaline with ammonium hydroxide, heated on the steam bath for 1/2 hour, and filtered. The filtrate was evaporated to approximately 30 ml of solution which was then acidified to pH4 with concentrated HCl. The solid was then collected. 1.6 g (58% yield) was obtained, m.p. 179°-180° C., white solid.

Provenance & Evidence