To a stirring solution of 7-Amino-2,3-dihydroinden-1-one (1.0 g, 6.8 mmol) in 48 % HBraq (2 mL) and EtOH (8 mL) was added NaNO2 (0.62 g, 8.6 mmol) dissolved in H20 (1 mL) at 0 °C and kept at 0 °C for 15 mm. Then a solution of CuBr (0.54 g, 3.6 mmol) in 48percent HBraq (8 mL) was added to the mixture at95 °C and kept at 95 °C for 15 mm. After consumption of the starting material (by TLC), the reaction mixture was diluted with water and extracted with EtOAc. The organic layer was washed with saturated NaHCO3 aq. Combined organic extracts were dried over anhydrous Na2504 and concentrated under reduced pressure to obtain a crude product, which was purified by silica gel column chromatography eluting with 10 % EtOAc /PE to afford 7-Bromo-1-indanone (0.54 g, 37 %) as an off-white solid. LC-MS: m/z = 212.0 [M+H]
