N,N-Dimethylaniline → Methyl 3-chloro-7-methoxy-1-(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoxaline-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 7-methoxy-1-[(4-methoxyphenyl)methyl]-2,3-dioxo-1,2,3,4-tetrahydroquinoxaline-6-carboxylate (24 g, 64.80 mmol) in toluene (300 mL) was added POCl3 (14.8 g, 96.52 mmol) and N,N-dimethylaniline (15.7 g, 129.75 mmol). The resulting solution was stirred overnight at 110° C. and concentrated in vacuo. The product was precipitated by the addition of methanol (150 mL) and collected by filtration to afford methyl 3-chloro-7-methoxy-1-(4-methoxybenzyl)-2-oxo-1,2-dihydroquinoxaline-6-carboxylate as a green solid (17 g, 65%).

Provenance & Evidence