16657-07-1

Synthesis of 4-bromo-1H-inden(d): 4-bromo-2,3-dihydro-1H-inden-1-ol (150 g, 704 mmol, 1 equiv) was suspended in a mixture of concentrated sulfuric acid (250 mL) and water (1.25 L). The reaction mixture was heated to reflux overnight. After completion of the reaction, it was cooled to room temperature and extracted with dichloromethane (1.5 L). The organic layer was washed sequentially with saturated sodium bicarbonate solution (1.5 L), dried over anhydrous sodium sulfate, and concentrated under reduced pressure to remove the solvent. The crude product obtained was purified by silica gel column chromatography (800 g silica gel), using heptane as eluent, to give 4-bromo-1H-indene (95 g, yield 69%) as a light yellow oil.

[1] Patent: WO2015/95188, 2015, A1. Location in patent: Paragraph 00163
[2] Angewandte Chemie - International Edition, 2010, vol. 49, # 38, p. 6877 - 6880
[3] Patent: US9249239, 2016, B2. Location in patent: Page/Page column 51; 52