Phosphorus oxychloride → Ethyl 4-chloro-1,6-naphthyridine-3-carboxylate

Participants

Reaction Steps

A mixture of 9.3 g of ethyl 4-hydroxy-1,6-naphthyridine-3-carboxylate (prepared according to J. Org. Chem. 15, 1224 (1950)) and 56 ml of phosphorous oxychloride is refluxed for 2 hours 40 minutes, then evaporated to dryness and the residue is treated with cold dilute ammonium hydroxide and methylene chloride. Insoluble material is removed by filtration, then organic layer is separated, washed with brine, dried over sodium sulfate and evaporated to dryness to yield ethyl 4-chloro-1,6-naphthyridine-3-carboxylate.

Provenance & Evidence