Methanesulfonic Acid → 7-Bromo-3,4-dihydroisoquinolin-1(2H)-one

Participants

Reaction Steps

Sodium azide (0.431 g, 6.63 mmol) was added slowly to a mixture of 6-bromo-2,3-dihydro-1H-inden-1-one (1 g, 4.74 mmol) and methanesulfonic acid (15 mL, 231 mmol) in DCM (30 mL) at 0° C. The mixture was stirred at rt for 15 hrs, then was carefully quenched with 1 M aqueous sodium hydroxide (50 mL). The aqueous layer was extracted with DCM (3×50 mL), and the combined organic layers were washed with water (20 mL) and brine (20 mL), dried and concentrated. The residue was purified by column chromatography (eluting with a gradient from 90:10 hexane-EtOAc to EtOAc) to give 7-bromo-3,4-dihydroisoquinolin-1(2H)-one as white solid (650 mg, 61%). 1H NMR (400 MHz, chloroform-d) δ 8.35 (1H, br. s.), 7.08-7.17 (1 H, m), 6.98-7.06 (1H, m), 6.95 (1H, d, J=1.98 Hz), 2.93 (2H, t, J=7.59 Hz), 2.49-2.68 (2H, m). Mass spectrum m/z 226, 228 (M+H)+.

Provenance & Evidence