Réaction #65397

Équation de réaction

sodium hydride

6-cyano-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazine

cyclopentene oxide

→

6-cyano-3,4-dihydro-4-(2-hydroxycyclopentan-1-yl)-2,2-dimethyl-2H-1,4-benzoxazine

Solvants

N,N-dimethylformamide

water

Conditions de réaction

Traitement

1. 1
   Températureafter cooling to room temperature
2. 2
   workup.STIRRINGThe mixture was stirred at 70° C. for 3 hours
3. 3
   Températureto cool
4. 4
   Extractionextracted with ethyl acetate
5. 5
   LavageThe extract was washed with water and aqueous sodium chloride solution
6. 6
   Séchagedried over anhydrous magnesium sulfate
7. 7
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
8. 8
   AutreThe residue was purified by silica gel column chromatography
9. 9
   Autrethe resulting crude crystals were recrystallized from ethyl acetate-hexane

Mode opératoire

In 20 ml of N,N-dimethylformamide was dissolved 1.0 g of 6-cyano-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazine followed by addition of 0.24 g of sodium hydride. The mixture was stirred at 70° C. for 1 hour and after cooling to room temperature, 0.5 ml of cyclopentene oxide was added. The mixture was stirred at 70° C. for 3 hours. The reaction mixture was then allowed to cool, diluted with water and extracted with ethyl acetate. The extract was washed with water and aqueous sodium chloride solution and dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography and the resulting crude crystals were recrystallized from ethyl acetate-hexane to give 0.53 g of 6-cyano-3,4-dihydro-4-(2-hydroxycyclopentan-1-yl)-2,2-dimethyl-2H-1,4-benzoxazine.

Source