Propionic anhydride → HCID 15580732, compound

Participants

Reaction Steps

A mixture of 5.0 g. of 3-amino-5-methyl-1-phenyl-2-pyrazoline (prepared in Example 5) and 25.0 ml. of propionic anhydride is allowed to remain at room temperature for 16 hours. The reaction mixture is poured into water to separate an oil which crystallizes. The solid is collected by filtration and dissolved in dichloromethane. The solution is passed through a short column of a hydrous magnesium silicate. The effluent is heated at reflux and hexane is added. The first heavy precipitate (purple color) is discarded. The solution is cooled and the ensuing precipitate is collected by filtration. The solid is again dissolved in dichloromethane, columnized and recrystallized with hexane to give 2.3 g. of the product of the Example as plates, m.p. 96.0°-96.5° C.

Provenance & Evidence