Sodium Carbonate → 8-chloro-7-methoxy-3,4-dihydroisoquinolin-1(2H)-one

Participants

Reaction Steps

To a mixture of 7-methoxy-3,4-dihydroisoquinolin-1(2H)-one (1c, 13.0 g, 73.9 mmol) in conc. H2SO4 (120 mL) was added portionwise NCS (10.4 g, 77.6 mmol) at 0° C. The reaction mixture was warmed to room temperature and stirred overnight. The reaction mixture was poured onto ice-water (200 mL). The solution was basified with Na2CO3 (s) to pH 8. The reaction mixture was extracted with EtOAc (2×200 mL). The combined organic layers were washed with brine (300 mL), dried over Na2SO4 and concentrated under vacuum. The residue was purified by column chromatography (petroleum ether/EtOAc, 1:1) to give 8-chloro-7-methoxy-3,4-dihydroisoquinolin-1(2H)-one (1d, 7.8 g, 50%) as a yellow solid.

Provenance & Evidence