954258-03-8

7-Fluorodihydroindole (4.5 g, 32.8 mmol) was used as a raw material and dissolved in dichloromethane (10 mL). To this solution was added N-bromosuccinimide (5.8 g, 32.8 mmol). The reaction mixture was stirred at room temperature for 2 hours. Subsequently, the mixture was concentrated under vacuum to remove the solvent. The crude product was purified by silica gel column chromatography with an eluent ratio of petroleum ether:ethyl acetate = 20:1 to afford 5-bromo-7-fluorodihydroindole (4.0 g, 56% yield) as a yellow solid.LCMS analysis showed the molecular ion peak M/Z (M+H) as 216.

[1] Patent: WO2016/86200, 2016, A1. Location in patent: Page/Page column 346
[2] Patent: US2008/221160, 2008, A1. Location in patent: Page/Page column 10