Ethanol → 4H-1-Benzopyran-4-one, 2,3-dihydro-, oxime

Participants

Reaction Conditions

Reaction Steps

A quantity (18.4 g.) of 4-chromanone was dissolved in 100 ml. ethanol with heating to the boiling temperature. To this hot solution was added 18.4 g. hydroxylamine hydrochloride and a hot aqueous solution of sodium acetate (36.8 g.) that had been dissolved in 50 ml. water heated on a steam bath. The reaction mixture was heated at the reflux temperature for 1.5 hrs. when a thin layer chromatogram indicated that the reaction was completed. After cooling the mixture to about 10° C., crystals formed. The crystals were collected on a filter, washed with water, and dried in air. There was thus obtained 18.63 g. of 4-chromanone oxime that had a melting point at 139° to 142° C. Recrystallization from methanol gave 16.5 g. of the compound having the same melting point (139° to 142° C.).

Provenance & Evidence