Sulfuric Acid → 3-Acetyl-2,4-dihydroxyquinoline

Participants

Reaction Conditions

Reaction Steps

2-(3-Oxo-butanoylamino)-benzoic acid methyl ester (383 mg, 1.63 mmol) was combined with diethyl ether (10 mL) and methanol (5 mL) and the mixture was stirred rapidly while a solution of sodium methoxide (25% solution, 1.63 mmol, 0.45 mL) in methanol (3 mL) was added over 10 minutes. The reaction then was heated at 40° C. overnight. Progress of the reaction was monitored by TLC (silica gel, hexane:EtOAc:CH2Cl2:acetone (3:3:3:1)) and analytical HPLC and upon its completion the mixture was acidified with 1 N sulfuric acid to form a solid. The solid was collected by filtration and then crystallized from hot acetic acid/acetonitrile/water to provide 3-acetyl-4-hydroxy-1H-quinolin-2-one (250 mg, 76%) as small colorless prisms, mp 258-262° C. (dec) (lit., 259° C.). LCMS MH+ 204.2.

Provenance & Evidence