Réaction #3217

Équation de réaction

diethyl oxosuccinate sodium salt

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

→

title compound

Rendement 24.0%

Diethyl 7-bromo-4-hydroxyquinoline-2,3-dicarboxylate

Rendement 24.0%

Solvants

dimethylformamide

DMF

Conditions de réaction

Traitement

1. 1
   AutreThe resulting reaction mixture
2. 2
   Températurerefluxed for 5 hr
3. 3
   TempératureAfter cooling to room temperature
4. 4
   Concentrationthe reaction mixture was concentrated
5. 5
   Autrethe residue was chromatographed over silica gel (eluant: ethyl acetate/methylene chloride; 5/95)
6. 6
   workup.ADDITIONThe fractions containing the desired material
7. 7
   Concentrationconcentrated
8. 8
   AutreThe solid residue was recrystallized from ethanol/ether

Mode opératoire

To a stirred mixture of diethyl oxosuccinate sodium salt (1.31 g, 6.23 mM) in dimethylformamide (DMF, 15 mL) under a nitrogen atmosphere was added a solution of 7-bromo-2H-3,1-benzoxazine-2,4(1H)-dione (1.50 g, 6.20 mM) in DMF (15 mL). The resulting reaction mixture was heated to 130° C. over 2.5 hr and then refluxed for 5 hr. After cooling to room temperature, the reaction mixture was concentrated and the residue was chromatographed over silica gel (eluant: ethyl acetate/methylene chloride; 5/95). The fractions containing the desired material were combined and concentrated. The solid residue was recrystallized from ethanol/ether to provide (0.54 g, 24%) the title compound as a tan solid, mp 233.5°-234.5° C.; MS(CI): 368, 369 (M+H).

Source