Sodium hydrosulfide → 7-Ethoxyquinoline-4(1H)-thione

Participants

Reaction Steps

4-Chloro(bromo)-7-ethoxyquinoline (180 mg) and 70% sodium hydrosulfide (250 mg) were dissolved in methanol(50 ml) and refluxed for 15 hours. This reaction mixture was evaporated under reduced pressure and the residue was developed by silica gel column chromatography [Wako Gel™ C-200, mixed solution of methylene chloride with methanol (9 : 1)]. Fractions corresponding to yellow spots were collected and evaporated to obtain crude crystals. The obtained crude crystals were recrystallized from 40% aqueous ethanol solution to obtain 107 mg of the titled compound. Melting Point: 171°-174° C.; MS m/z: 205 (M+); NMR(DMSO-d6)δ: 1.40(3H, t, J=6.9 Hz), 4.15(2H, q, J=6.9 Hz), 7.02(1H, d, J=1.3 Hz), 7.09(1H, dd, J=2.3, 9.2 Hz), 7.15(1H, d, J=6.5 Hz), 7.73-7.78(1H, m), 8.58(1H, d, J=9.2 Hz), 12.68(1H, brs)

Provenance & Evidence