Reaktion #3200

Reaktionsgleichung

sodium hydroxide

5,7-dichloro-2H-3,1-benzoxazine-2,4(1H)-dione

→

methyl 2-amino-4,6-dichlorobenzoate

Ausbeute 92.2%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto cool to room temperature
2. 2
   Einengenconcentrated
3. 3
   workup.ADDITIONThe residue was diluted with water
4. 4
   Extraktionthe resulting mixture extracted with ethyl acetate
5. 5
   TrocknenThe combined extracts were dried (MgSO4)
6. 6
   Filtrationfiltered
7. 7
   Einengenconcentrated

Vorschrift

To a stirred solution of sodium hydroxide (0.070 g, 1.8 mM) in methanol (8.5 mL) was added 5,7-dichloro-2H-3,1-benzoxazine-2,4(1H)-dione (4.13 g, 17.8 mM). The reaction mixture was stirred at 55° C. for 2 hr, allowed to cool to room temperature and concentrated. The residue was diluted with water and the resulting mixture extracted with ethyl acetate. The combined extracts were dried (MgSO4), filtered and concentrated to leave the methyl 2-amino-4,6-dichlorobenzoate (3.61 g, 92.1%) as a brown solid; MS(CI): 220 (M+H).

Quelle