Acetic Acid → 5-methoxycarbamoylmethyl-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]-quinoxaline-2,3-dione

Participants

Reaction Steps

9-Bromo-5-methoxycarbonylmethyl-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]quinoxaline-2,3-dione (1.15 g, 3.26 mmol) in a mixture of THF (5 mL), DMF (10 mL), and acetic acid (8 mL) was hydrogenated over palladium on carbon (300 mg) under atmospheric pressure of hydrogen at room temperature for 5 h. The mixture was passed through celite and concentrated. The residue was purified by silica gel column chromatography with ethyl acetate to give 700 mg of 5-methoxycarbamoylmethyl-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]-quinoxaline-2,3-dione (79%): 227°~229° C. (dec); 1H NMR (270 MHz, DMSO-d6) δ12.00 (bs, 1H), 6.97~7.12 (m, 2H), 5.06~5.16 (m, 1H), 3.63 (s, 3H), 2.97 (ddd, 1H, J=17.1, 13.5, 4.5 Hz), 2.79 (dm, 1H, J=17.1 Hz), 2.54~2.69 (m, 2H), 2.12 (dm, 1H, J=13.5 Hz), 1.82~2.00 (m, 1H).

Provenance & Evidence