Dimethylformamide → 1-Methyl-2-oxo-1,2-dihydroquinoline-3-carbonyl chloride

Participants

Reaction Conditions

Reaction Steps

0.76 g (3.7 mmol) of 1-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid was dissolved in dichloromethane (50 mL), and 1.0 mL (12 mmol) of oxalyl chloride was added to the above solution. Two droplets of N,N-dimethylformamide were added to this mixture, and the resulting mixture was stirred for 1 hour at 40° C. The reaction solution was concentrated under reduced pressure, and thus 1-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid chloride was obtained. The acid chloride thus obtained was dissolved in acetonitrile (30 mL), and this solution was added to an acetonitrile (50 mL) solution of 0.46 g (4.1 mmol) of 1,3-cyclohexanedione and 0.63 mL (4.5 mmol) of triethylamine under ice cooling. The mixture was stirred overnight at room temperature. This reaction mixture was poured into water and was extracted with ethyl acetate. The organic phase was washed with water, an aqueous solution of sodium hydrogen carbonate, and water in this order, and then was dried and concentrated. The residue was purified by column chromatography (ethyl acetate:n-hexane=1:4 to 1:0), and thus 0.48 g (yield: 43%) of the title compound was obtained as a pale yellow powder.

Provenance & Evidence