Reaktion #538270

Reaktionsgleichung

2-(3,5-difluorophenyl)cyclopentanone

carbonisocyanatidic chloride

→

7-(3,5-difluorophenyl)-6,7-dihydrocyclopenta[e][1,3]oxazine-2,4(3H,5H)-dione

Ausbeute 10.9%

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturUpon cooling to room temperature
2. 2
   Waschenwashed with saturated aqueous solution of sodium bicarbonate
3. 3
   SonstigeThe organic layer was separated
4. 4
   Extraktionthe aqueous layer was extracted with ethyl acetate
5. 5
   TrocknenThe combined organic extracts were dried over anhydrous magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   SonstigeThe solvent was removed in vacuum
8. 8
   Sonstigethe residue was purified by column chromatography on silica gel

Vorschrift

A mixture of 2-(3,5-difluorophenyl)cyclopentanone (4.765 g, 24.29 mmol) and carbonisocyanatidic chloride (4.61 g, 43.7 mmol) was heated at 58° C. for 1 h and at 130° C. for 2 h. Upon cooling to room temperature, the reaction mixture was dissolved in ethyl acetate and washed with saturated aqueous solution of sodium bicarbonate. The organic layer was separated and the aqueous layer was extracted with ethyl acetate. The combined organic extracts were dried over anhydrous magnesium sulfate and filtered. The solvent was removed in vacuum and the residue was purified by column chromatography on silica gel to give 7-(3,5-difluorophenyl)-6,7-dihydrocyclopenta[e][1,3]oxazine-2,4(3H,5H)-dione (700 mg, 2.64 mmol, 10.87% yield). LC-MS (M+H)+=266.1. 1H NMR (500 MHz, CDCl3) δ ppm 8.79 (1H, br s), 6.68-6.86 (3H, m), 4.22 (1H, br s), 2.87 (1H, dt, J=7.0, 4.4 Hz), 2.63-2.82 (2H, m), 2.15 (1H, br s).

Quelle