Piperazine → HCID 59699580, compound

Participants

Reaction Steps

A solution of 1-benzyl-4-chloro-2-oxo-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic acid ethyl ester (4) (1.2 g, 3.5 mmol) in dichloromethane was added slowly to a stirred solution of piperazine (0.9 g, 10.5 mmol) in dichloromethane at room temperature. The solution was stirred overnight at room temperature. The solvent was evaporated and the residue was suspended in water, sonicated briefly, and extracted with dichloromethane. The combined organic phase was subsequently washed by water and brine, dried over Na2SO4, and evaporated to yield 1.12 g (82%) of 1-benzyl-2-oxo-4-piperazin-1-yl-1,2-dihydro-[1,8]-naphthyridine-3-carboxylic acid ethyl ester (5) as yellow solids. MP: 120° C.; 1H-NMR (DMSO-d6): δ 1.30 (t, J=6.9 Hz, 3H), 2.28 (m, 4H), 3.03 (m, 4H), 4.28 (q, J=6.9 Hz, 2H), 5.55 (s, 2H), 7.16-7.28 (m, 5H), 7.36 (m, 1H), 8.25 (dd, J=1.5, 7.5 Hz, 1H), 8.63 (dd, J=1.5, 7.5 Hz, 1H); EIMS: 393 (M+1), 415 (M+23).

Provenance & Evidence