Hydrogen Peroxide → 5-Methyl-1-(propan-2-yl)-1,2-dihydro-3H-pyrazol-3-one

Participants

Reaction Conditions

Reaction Steps

1-(1-methylethyl)-5-methyl-3-pyrazolidinone (390 g; 2.74 mol) is dissolved in acetic acid (170 ml) with warming. 35% aqueous hydrogen peroxide (260 ml; 3.0 mol) is added within 3 h while keeping the temperature at about 65° C. The reaction mixture is then stirred at about 20 to 25° C. for 15 h. Water (1.2 L) is then added and the pH of the mixture is adjusted to about 7 by means of addition of approx. 1 L 50%-weight aqueous sodium hydroxide solution. Upon cooling to 5° C. the reaction mixture is filtered. The product is washed with water and dried at about 50° C. Colourless crystals are obtained.

Provenance & Evidence