Ethyl 8-ethoxy-2H-[1,3]dioxolo[4,5-g]quinoline-7-carboxylate → HCID 15618563, compound

Participants

Reaction Steps

To 120 ml of 5% ethanolic sodium hydroxide solution was added 6 g of ethyl 4-ethoxy-6,7-methylenedioxyquinoline-3-carboxylate with stirring, and the mixture was stirred further for 15 minutes at room temperature then concentrated to a small volume under reduced pressure. A small amount of water was added to the residue, the pH of the solution was adjusted to 5 by the addition of hydrochloric acid, and the precipitate thus formed was filtered, washed with water and dried to provide 5.2 g of almost pure 4-ethoxy-6,7-methylenedioxyquinoline-3-caboxylic acid having a melting point of 250°-253°C. Recrystallization from dimethyl sulfoxide gave colorless needles having a melting point of 252°C (decomposed).

Provenance & Evidence