Potassium Nitrate → HCID 59003036, compound

Participants

Reaction Steps

To a solution of ethyl (3R)-9,10-difluoro-3-fluoromethyl-2,3-dihydro-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate (500 mg, 1.53 mmol) in H2SO4 (5.0 mL), was added KNO3 (216 mg, 2.14 mmol) under cooling with ice, the whole mixture was stirred under cooling with ice for 2 h. The reaction mixture was poured into ice-water and the resulting precipitates were collected by filtration. The filtered precipitates were washed with water, and dried in vacuo to give ethyl (3R)-9,10-difluoro-3-fluoromethyl-2,3-dihydro-8-nitro-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate (453 mg, 80%) as a pale brown powder.

Provenance & Evidence