Lawesson's reagent → 6-bromo-5-fluoro-3,4-dihydroquinoline-2(1H)-thione

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 6-bromo-5-fluoro-3,4-dihydroquinolin-2(1H)-one (146-5; 0.45 g, 0.00184 mol) in toluene (10 mL) was added Lawesson's reagent (0.745 g, 1.00184 mol). Reaction mass heated at 120° C. and maintained for 2 h. The reaction mixture was cooled, quenched with sodium bicarbonate solution and extracted with ethyl acetate (3×30 mL). The combined organic layer was washed with saturated aqueous sodium chloride solution, dried over sodium sulphate and concentrated under vacuum to afford the title compound. 1H NMR (400 MHz, DMSO) δ 12.364 (s, 1H), 7.543-7.503 (t, J=8.0 Hz, 1H), 6.895-6.874 (d, J=0.1-8.4 Hz, 1H) 2.968-2.930 (t, J=7.2 Hz, 2H), 2.843-2.805 J 8.0 Hz, 2H): MS (M 1): 260.1.

Provenance & Evidence