Phosgene → 6-Fluoro-1,3-benzoxazol-2(3H)-one

To 5.0 g (39.3 mmol) 2-amino-5-fluorophenol in 150 ml of CH2Cl2 at 0° C. was added 13.4 (98 mmol) of potassium carbonate and 23 g (47 mmol) of 20 wt. % phosgene in toluene. After warming to room temperature, the reaction was stirred an additional hour before quenching onto 200 ml ice/water. The layers were separated and the aqueous phase was extracted with EtOAc (1×100 ml) before the organics were combined and dried over Na2SO4. The solvent was removed in vacuo to give 5.76 g (96% yield) of the desired product as determined by 1H NMR.

1. custombefore quenching onto 200 ml ice/water
2. customThe layers were separated
3. extractionthe aqueous phase was extracted with EtOAc (1×100 ml) before the
4. dry with materialdried over Na2SO4
5. customThe solvent was removed in vacuo

ORD record

ord-c0d0f216f7a4464b823006ecd68e6c7a

Source dataset

uspto-grants-1995_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05393735