Reaktion #702423

Reaktionsgleichung

chloroacetone

2,3-dihydro-2,2-dimethyl-6-hydroxy-4H-1,3-benzoxazin-4-one

potassium carbonate

chloroacetone

→

2,3-dihydro-2,2-dimethyl-6-(2-oxopropoxy)-4H-1,3-benzoxazin-4-one

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder reflux for 30 hours
2. 2
   Temperaturthe reaction mixture is refluxed for a further 15-20 hours
3. 3
   FiltrationThe reaction mixture is filtered
4. 4
   Temperaturwhilst still warm
5. 5
   Waschenthe residue is thoroughly washed with acetone
6. 6
   Einengenthe combined filtrate is concentrated by evaporation
7. 7
   SonstigeThe crystalline residue is recrystallised from toluene

Vorschrift

70 g of 2,3-dihydro-2,2-dimethyl-6-hydroxy-4H-1,3-benzoxazin-4-one in 400 ml of acetonitrile with 100 g of potassium carbonate and 32 ml of chloroacetone are stirred under reflux for 30 hours. After the addition of a further 3.2 ml of chloroacetone, the reaction mixture is refluxed for a further 15-20 hours. The reaction mixture is filtered whilst still warm; the residue is thoroughly washed with acetone, and the combined filtrate is concentrated by evaporation. The crystalline residue is recrystallised from toluene and yields 2,3-dihydro-2,2-dimethyl-6-(2-oxopropoxy)-4H-1,3-benzoxazin-4-one, m.p. 125°-126°.

Quelle