Ammonia → HCID 86682953, compound

Participants

Reaction Steps

A mixture of 6-chloro-4-hydroxy-2-isopropyl-quinoline-3-carboxylic acid methyl ester (prepared as described in example 20 step A, 2 g, 7.15 mmol) and phosphorous oxychloride (10 ml) under nitrogen was refluxed for 1 h. After cooling the reaction mixture to room temperature, the mixture was poured onto ice cold water and the pH of the aqueous phase was adjusted to 7 with aqueous ammonia solution. The aqueous phase was extracted with ethyl acetate and the combined organic phases were washed with brine, dried over sodium sulfate and concentrated in vacuo to give a crude residue which was purified by flash column chromatography (100-200 mesh silica, eluting with 5-10% EtOAc in hexane) to afford pure 4,6-dichloro-2-isopropyl-quinoline-3-carboxylic acid methyl ester (1.3 g, 61%) as pale yellow solid. LC-MS: 298 (M+H)+.

Provenance & Evidence