Dabco → HCID 59699584, compound

Participants

Reaction Conditions

Reaction Steps

DABCO (0.7 g, 6.3 mmol) was added to a solution of 4-chloro-2-oxo-1,2-dihydro-[1,6]-naphthyridine-3-carboxylic acid ethyl ester (120) (0.8 g, 3.16 mmol) and piperazine-1-yl-thiophene-2-yl-methanone (0.93 g, 4.74 mmol) DMA at room temperature. The solution was heated at 110° C. for 2 h. The solution was cooled and poured into ice cold 10% ammonium chloride solution in water. The solids formed were filtered, washed by water, and dried to yield 1.2 g (92%) of 2-oxo-4-[4-(thiophene-2-carbonyl)-piperazin-1-yl]-1,2-dihydro-[1,6]-naphthyridin-3-carboxylic acid ethyl ester (121) as white solids. MP: 231° C.; 1H-NMR (DMSO-d6): δ 1.28 (t, J=7.2 Hz, 3H), 3.18 (m, 4H), 3.89 (m, 4H), 4.27 (q, J=7.2 Hz, 2H), 7.14 (dd, J=3.6, 4.8 Hz, 1H), 7.18 (d, J=6.0 Hz, 1H), 7.47 (d, J=3.6 Hz, 1H), 7.80 (d, J=4.8 Hz, 1H), 8.51 (d, J=5.6 Hz, 1H), 8.91 (s, 1H); EIMS m/z 413 (M+1).

Provenance & Evidence