Diethyl Malonate → Ethyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylate

Participants

Reaction Steps

To a solution of methyl anthranilate (121 g, 0.8 mol) and diethyl malonate (128 g, 0.8 mol) in ethanol (900 mL) was added a 20% solution (274 g) of sodium ethoxide in ethanol, and the mixture was stirred at room temperature for 30 min. Ethanol was evaporated, and the mixture was stirred at 140° C. for 12 hr. After cooling, the obtained solid was washed with diethyl ether, and dissolved in water. Insoluble materials were filtered off, the filtrate was acidified with 5N hydrochloric acid, and the precipitated solid was collected by filtration. The obtained solid was washed with water, and dried under reduced pressure to give the title compound (161 g, 86%) as a pale-yellow powder.

Provenance & Evidence