8-FLUORO-4-HYDROXY-2-(TRIFLUOROMETHYL)QUINOLINE synthesis

Yield:-

Reaction Conditions:

with hydrogenchloride;phosphoric acid in water;benzene

Steps:

275.1 Synthesis of 3-{(2S,4S)-4-[4-(8-fluoro-2-trifluoromethyl-4-quinolyl)-1-piperazinyl]-2-pyrrolidinylcarbonyl}-1,3-thiazolidine dihydrochloride
(1) 2-Fluoroaniline (10.0 g), ethyl trifluoroacetoacetate (16.6 g) and concentrated hydrochloric acid (0.1 mL) were dissolved in benzene (40 mL), and the mixture was refluxed in a reaction vessel equipped with Dean-Stark trap for 7 hr. The reaction mixture was concentrated under reduced pressure and 75% phosphoric acid (40 mL) was added thereto. The mixture was stirred at 110°C for 5 hr. The reaction mixture was added to water, neutralized with sodium hydrogencarbonate, and extracted with ethyl acetate. The extract was concentrated under reduced pressure to give 8-fluoro-4-hydroxy-2-trifluoromethylquinoline (1.77 g).

References:

WELFIDE CORPORATION EP1308439, 2003, A1