Phosphorus oxychloride → Ethyl 4,7-dichloroquinoline-3-carboxylate

Participants

Reaction Steps

A mixture of 30 g. of 7-chloro-4-hydroxyquinoline-3-carboxylic acid, ethyl ester, m.p. 299°-301°, (0.12 mol.) and 250 ml. of phosphorus oxychloride is refluxed for 4.5 hours. After removing the excess phosphorus oxychloride, the residue is triturated with water and dissolved in ether. The ethereal solution is washed with aqueous sodium carbonate (5%) and water, dried with sodium sulfate and the solvent is removed. The residual 4,7-dichloroquinoline-3-carboxylic acid, ethyl ester is triturated with petroleum ether (40°-60°), filtered off and dried; yield: 22 g. (68%); m.p. 81°-82°.

Provenance & Evidence