General procedure for the synthesis of 7-bromo-2,3-dihydro-isoindol-1-one from methyl 2-bromo-6-methylbenzoate: methyl 2-bromo-6-methylbenzoate (65.9 g, 288 mmol), N-bromosuccinimide (NBS, 53.8 g, 302 mmol), and azobisisobutyronitrile (AIBN, 2.3 g, 14 mmol) were dissolved in benzene ( 1 L) in benzene and heated to reflux for 8 hours. After completion of the reaction, the mixture was cooled to 25 °C, the succinimide was removed by filtration and the filter cake was washed with hexane. The filtrate was concentrated and dissolved in tetrahydrofuran (THF, 1 L), concentrated ammonia (NH4OH, 290 mL) was added, and stirred at 25 °C for 4 hours. The reaction solution was diluted with water (1 L) and extracted with ethyl acetate (EtOAc, 3 x 300 mL). The organic phases were combined, concentrated and purified by silica gel column chromatography (SiO2) to afford 7-bromo-2,3-dihydro-isoindol-1-one (28.9 g, 47% yield) as an off-white solid. 1H NMR (400 MHz, CDCl3) δ 7.73 (br s, 1H), 7.62 (d, J = 7.2 Hz, 1H), 7.43 (m, 2H),. 4.42 (s, 2H); mass spectrum (ESI) m/z: not detected (MH+).
