Реакция #538270

Уравнение реакции

2-(3,5-difluorophenyl)cyclopentanone

carbonisocyanatidic chloride

→

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

Выход 10.9%

Растворители

ethyl acetate

Условия реакции

Обработка

1. 1
   ТемператураUpon cooling to room temperature
2. 2
   Промывкаwashed with saturated aqueous solution of sodium bicarbonate
3. 3
   ДругоеThe organic layer was separated
4. 4
   Экстракцияthe aqueous layer was extracted with ethyl acetate
5. 5
   СушкаThe combined organic extracts were dried over anhydrous magnesium sulfate
6. 6
   Фильтрацияfiltered
7. 7
   ДругоеThe solvent was removed in vacuum
8. 8
   Другоеthe residue was purified by column chromatography on silica gel

Методика

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).

Источник