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

HRID 462215

Reaction equation

HRID 462215 reaction equation
[O:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4](=O)[CH2:3][CH2:2]1.C(O)C.Cl.[NH2:16][OH:17].C([O-])(=O)C.[Na+]>O>[O:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4](=[N:16][OH:17])[CH2:3][CH2:2]1

Participants

6

Reactant 4

HCID 702EthanolHCID 68110ChromanoneHCID 443297Hydroxyamine hydrochlorideHCID 517045Sodium Acetate

Product 1

HCID 44866984H-1-Benzopyran-4-one, 2,3-dihydro-, oxime

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
10 °C

Procedure

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.).

Workup

  1. additionTo this hot solution was added 18.4 g
  2. temperatureThe reaction mixture was heated at the reflux temperature for 1.5 hrs
  3. customcrystals formed
  4. customThe crystals were collected on a filter
  5. washwashed with water
  6. customdried in air
  7. customat 139° to 142° C
  8. customRecrystallization from methanol
  9. customgave 16.5 g
  10. customthe same melting point (139° to 142° C.)

Sources & evidence

ORD record
ord-a250119075af42cf88b2241e253ffbda
Source dataset
uspto-grants-1977_12
Patent number
US04065574

Linked notes

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