反应详情

温度

130 °C

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).

1. temperatureUpon cooling to room temperature
2. washwashed with saturated aqueous solution of sodium bicarbonate
3. customThe organic layer was separated
4. extractionthe aqueous layer was extracted with ethyl acetate
5. dry with materialThe combined organic extracts were dried over anhydrous magnesium sulfate
6. filtrationfiltered
7. customThe solvent was removed in vacuum
8. customthe residue was purified by column chromatography on silica gel