Sulfuric Acid → 6,7-Dimethoxy-4-(3,4-dimethoxyphenyl)-3-ethoxycarbonylquinoline-2-acetic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

Conc. sulfuric acid (1.5 ml) was added to a mixture of 2-amino-4,5,3',4'-tetramethoxybenzophenone (50.0 g), diethyl acetonedicarboxylate (35.0 g) and acetic acid (400 ml), and the mixture was stirred at 100° C. for 2.5 hours. The reaction mixture was concentrated under reduced pressure. The residue was poured into water, neutralized with an aqueous saturated solution of sodium bicarbonate, and extracted with chloroform. The chloroform layer was washed with water and dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The residual crystals were recrystallized from acetone to give ethyl 4-(3,4-dimethoxyphenyl)-6,7-dimethoxy-3-ethoxycarbonylquinoline-2-acetate (48.8 g, 64%). Colorless prisms, mp. 146°-147° C.

Provenance & Evidence