Reaction #4644

Reaction equation

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

allyl bromide

potassium carbonate

→

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

Solvents

acetonitrile

Conditions

Workup

1. 1
   FiltrationThe reaction mixture is filtered
2. 2
   Temperaturewhilst warm
3. 3
   Concentrationthe filtrate is concentrated by evaporation
4. 4
   Filtrationthe remaining crystals are suction-filtered after trituration with ether

Procedure

A solution of 9.65 g of 2,3-dihydro-2,2-dimethyl-6-hydroxy-4H-1,3-benzoxazin-4-one and 9.1 g of allyl bromide in 150 ml of acetonitrile is refluxed for 5 hours, whilst stirring, with the addition of 10.3 g of dry potassium carbonate. The reaction mixture is filtered whilst warm, the filtrate is concentrated by evaporation and the remaining crystals are suction-filtered after trituration with ether. The crude 2,3-dihydro-2,2-dimethyl-6-(1-propen-3-yloxy)-4H-1,3-benzoxazin-4-one obtained in this manner melts at 137°-138°.

Source