Potassium Hydroxide → HCID 86732805, compound

Participants

Reaction Conditions

Reaction Steps

To a suspension of 4-methoxybenzyl 1-ethyl-5-fluoro-6,7-bis((4-methoxybenzyl)oxy)-4-oxo-1,4-dihydroquinoline-3-carboxylate (68 g, 108 mmol) in a mixture of Methanol (250 mL) and Water (125 mL) was added KOH (12.16 g, 217 mmol) portionwise. The resulting mixture was stirred at 90° C. for 3 h. LCMS indicated completion of the reaction. The reaction mixture was cooled down to r.t. and concentrated, and was then diluted with water and adjusted pH to 1 using 6 N HCl (aq.). The precipitates were collected by filtration and dried to afford 1-ethyl-5-fluoro-6,7-bis((4-methoxybenzyl)oxy)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (50 g, 99 mmol, 91% yield) as a brown solid. LCMS: (M+H)+: 508.2.

Provenance & Evidence