Reaction #4622

Reaction equation

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

potassium carbonate

1,2-dibromoethane

→

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

Conditions

Workup

1. 1
   Temperatureis refluxed for 4 hours
2. 2
   OtherThe semi-liquid reaction mixture
3. 3
   Extractionis extracted 3 to 4 times whilst hot with 1 liter of methanol each time
4. 4
   Concentrationthe combined methanol extracts are concentrated by evaporation
5. 5
   Otherthe residue is recrystallised from methanol

Procedure

A mixture of 48.2 g of 2,3-dihydro-2,2-dimethyl-6-hydroxy-4H-1,3-benzoxazin-4-one, 70 g of potassium carbonate and 250 ml of 1,2-dibromoethane is refluxed for 4 hours whilst stirring. The semi-liquid reaction mixture is extracted 3 to 4 times whilst hot with 1 liter of methanol each time; the combined methanol extracts are concentrated by evaporation and the residue is recrystallised from methanol. 6-(2-Bromoethoxy)-2,3-dihydro-2,2-dimethyl-4H-1,3-benzoxazin-4-one having a melting point of 190°-195° is obtained.

Source