Ethyl 5-amino-6,7-difluoro-1,4-dihydro-4-oxo-1-(tetrahydropyran-4-yl)-3-quinolinecarboxylate → 5-Amino-6,7-difluoro-1,4-dihydro-4-oxo-1-(tetrahydropyran-4-yl)-3-quinolinecarboxylic acid

Participants

Reaction Steps

A suspension of ethyl 5-amino-6,7-difluoro-1,4-dihydro-4-oxo-1-(tetrahydropyran-4-yl)-3-quinolinecarboxylate (70.0 mg, 0.199 mmol) in a mixture of H2SO4/H2O/AcOH (1:5:6, 3 mL) was heated under reflux for 1 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 5-amino-6,7-difluoro-1,4-dihydro-4-oxo-1-(tetrahydropyran-4-yl)-3-quinolinecarboxylic acid (51.8 mg, 80%) as a yellow powder.

Provenance & Evidence