Phosphorus oxychloride → Ethyl 2-chloro-6,7-dimethoxy-4-(3,4-dimethoxyphenyl)quinoline-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl 6,7-dimethoxy-4-(3,4-dimethoxyphenyl)-2(1H)-quinolone-3-carboxylate (5.0 g) and phosphorus oxychloride (POCl3)(6.3 ml) was stirred at 100 to 110° C. for 80 minutes. The reaction mixture was concentrated under reduced pressure. The residue was poured into water, neutralized with an aqueous saturated sodium bicarbonate solution and extracted with chloroform. The chloroform layer was washed with water and dried over magnesium sulfate, and the solvent was evaporated. The residual oil was subjected to column chromatography on silica gel. The fractions eluted with chloroform gave ethyl 2-chloro-6,7-dimethoxy-4-(3,4-dimethoxyphenyl)quinoline-3-carboxylate (3.8 g, 73%) which was then recrystallized from ethyl acetate-hexane. mp. 168°-169° C.

Provenance & Evidence