The condensation of 2-fluoroaniline (I) with diethyl ethoxymethylene malonate (II) at 130 C afforded enamine (III), which was further cyclized to ethyl 8-fluoro-4-hydroxy-3-quinolinecarboxylate (IV) upon heating at 250 C. Condensation of (III) with neat 4-chlorobenzylamine (V) then provided the desired carboxamide.
The condensation between 4-iodoaniline (I) and diethyl ethoxymethylenemalonate (II) at 130 C, followed by cyclization in diphenyl ether at 250 C, furnished ethyl 4-hydroxy-6-iodoquinoline-3-carboxylate (III). Subsequent reaction of ester (III) with 4-chlorobenzylamine (IV) at 180 C produced the corresponding amide (V). Finally, coupling of (V) with propargyl alcohol (VI) in the presence of CuI and palladium catalyst afforded the desired (hydroxypropynyl)quinoline.