Water → 5,8-dichloro-7-hydroxy-3,4-dihydroisoquinolin-1(2H)-one

Participants

Reaction Steps

Boron tribromide (10 mL) was added to a cooled (0° C.) solution of tert-butyl 5,8-dichloro-7-methoxy-1-oxo-3,4-dihydroisoquinoline-2(1H)-carboxylate (296f, 14.5 g, 45.4 mmol) in dry dichloromethane (100 mL). The mixture was stirred at room temperature overnight, then water (10 mL) was added, causing a precipitate to form. The precipitate was collected by filtration, washed with water (500 mL), and dried to give 5,8-dichloro-7-hydroxy-3,4-dihydroisoquinolin-1(2H)-one (296g, 9.2 g, 95% yield) as a light yellow solid. 1H NMR (400 MHz, DMSO-d6): δ 10.58 (s, 1H), 8.17 (s, 1H), 7.13 (s, 1H), 3.25-3.23 (m, 2H), 2.83-2.80 (t, J=6.2 Hz, 2H). MS: 232 [M+1].

Provenance & Evidence