Reaktion #6460

Reaktionsgleichung

5-benzoyl-3,4-dihydro-2H-1,4-benzoxazine

pyridine

bromoacetyl bromide

water

→

4-bromoacetyl-5-benzoyl-3,4-dihydro-2H-1,4-benzoxazine

Ausbeute 69.4%

Lösungsmittel

methylene chloride

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   SonstigeThe organic layer was separated
3. 3
   Waschenwashed with water
4. 4
   Trocknendried over magnesium sulfate
5. 5
   Sonstigeevaporated
6. 6
   SonstigeThe residue was crystallized with a mixture of diisopropyl ether and ethyl acetate
7. 7
   FiltrationThe crystals were collected by filtration

Vorschrift

To a solution of 5-benzoyl-3,4-dihydro-2H-1,4-benzoxazine (5.74 g), pyridine (1.9 g) and methylene chloride (100 ml) was dropwise added a solution of bromoacetyl bromide (5.82 g) in methylene chloride (5 ml) at room temperature. After the mixture was stirred for 1.0 hour at the same temperature, water (100 ml) was added thereto under stirring. The organic layer was separated, washed with water, dried over magnesium sulfate and evaporated. The residue was crystallized with a mixture of diisopropyl ether and ethyl acetate. The crystals were collected by filtration to give 4-bromoacetyl-5-benzoyl-3,4-dihydro-2H-1,4-benzoxazine (6.0 g).

Quelle