N,N-Dimethylaniline → Methyl 3-chloro-2-(4-fluorophenyl)quinoxaline-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

Into a 100-mL round-bottom flask, was placed methyl 2-(4-fluorophenyl)-3-oxo-1,2,3,4-tetrahydroquinoxaline-6-carboxylate (1.2 g, 4.00 mmol, 1.00 equiv), POCl3 (12.2 g, 80.26 mmol, 20.00 equiv), N,N-dimethylbenzenamine (4.9 g, 40.50 mmol, 10.00 equiv). The resulting solution was stirred for overnight at 110° C. in an oil bath. The resulting mixture was concentrated under vacuum and diluted with 50 mL of water. The pH value of the aqueous solution was adjusted to 7 with sodium bicarbonate (4 mol/L). The resulting mixture was concentrated under vacuum and purified by silica gel chromatography with ethyl acetate/petroleum ether (1:40). This resulted in 0.5 g (40%) of methyl 3-chloro-2-(4-fluorophenyl)quinoxaline-6-carboxylate as a white solid.

Provenance & Evidence