Reaktion #538256

Reaktionsgleichung

2-(4-chlorophenyl)cyclopentanone

carbonisocyanatidic chloride

→

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

Ausbeute 51.1%

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

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

Vorschrift

A solution of 2-(4-chlorophenyl)cyclopentanone (7.80 g, 40.1 mmol) and carbonisocyanatidic chloride (7.61 g, 72.1 mmol) was stirred at 58° C. in a high-pressure vessel for 1 h. The temperature was raised to 130° C. and the reaction mixture was stirred for an additional 2 h. After cooling to rt, the reaction mixture solidified. The solid residue 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 twice with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate and filtered. The solvent was removed in vacuum and the oily residue was purified by column chromatography on silica gel to provide 7-(4-chlorophenyl)-6,7-dihydrocyclopenta[e][1,3]oxazine-2,4(3H,5H)-dione (5.4 g, 20.48 mmol, 51.1% yield). LC-MS (M+H)+=264.2. 1H NMR (500 MHz, CDCl3) δ ppm 7.32 (2H, d, J=8.5 Hz), 7.12 (2H, d, J=8.5 Hz), 4.15-4.25 (1H, m), 2.56-2.93 (4H, m).

Quelle