Reaktion #2204548

Reaktionsgleichung

2,4-dioxo-1,4-dihydro-2H-3,1-benzoxazine-6-carboxylic acid

→

white powder

Ausbeute 84.0%

4-amino-3-(methoxycarbonyl)benzoic acid

Ausbeute 84.0%

Lösungsmittel

dimethylformamide

methanol

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenThe reaction medium is concentrated under reduced pressure
2. 2
   Extraktionextracted with ethyl acetate
3. 3
   WaschenThe organic phase is washed with a saturated sodium chloride solution
4. 4
   Trocknendried over sodium sulphate
5. 5
   Einengenconcentrated under reduced pressure
6. 6
   SonstigeThe solid obtained
7. 7
   Filtrationfiltered
8. 8
   Sonstigedried

Vorschrift

150 mg (1.21 mmol) of 4-dimethylaminopyridine are added to 2.5 g (12.1 mmol) of 2,4-dioxo-1,4-dihydro-2H-3,1-benzoxazine-6-carboxylic acid [described in J. Med. Chem., (1981), 24(6), 735-742] in solution in 10 ml of dimethylformamide and 10 ml of methanol, and the mixture is heated at 60° C. for 3 hours. The reaction medium is concentrated under reduced pressure. The residue is taken up in water and extracted with ethyl acetate. The organic phase is washed with a saturated sodium chloride solution, dried over sodium sulphate and concentrated under reduced pressure. The solid obtained is taken up in ethyl acetate, filtered and dried. 1.98 g of a white powder are obtained.

Quelle