15115-60-3

1109230-25-2

The general procedure for the synthesis of 5-bromo-3,4-dihydroisoquinolin-1(2H)-one using 4-bromoindan-1-one as starting material was as follows: 4-bromoindan-1-one (4.00 g, 18.9 mmol) and methanesulfonic acid (20.2 mL, 310 mmol) were dissolved in dichloromethane (180 mL) at 0 °C, followed by the slow addition of sodium azide (2.46 g, 37.9 mmol). The reaction mixture was gradually warmed to room temperature and stirred continuously for 16 hours. Upon completion of the reaction, the mixture was poured into 10% aqueous sodium hydroxide solution (200 mL) and extracted with dichloromethane (100 mL). The organic layers were combined and dried over anhydrous sodium sulfate, followed by concentration under reduced pressure to remove the solvent. The crude product was purified by recrystallization from ethyl acetate (40 mL) to afford the target compound 5-bromo-3,4-dihydroisoquinolin-1(2H)-one (3.98 g, 17.6 mmol, 93% yield) as a white powder. The product was analyzed by LCMS showing a purity of 96% with a retention time (Rt) of 1.225 min, and electrospray ionization mass spectrometry (ESMS) showing a m/z of 226 ([M+H]+).