226070-05-9

111-25-1

1133-80-8

226070-05-9

Example 1: Synthesis of 2-bromo-9,9-dihexylfluorene 1. 2-Bromofluorene (9.8 g, 1.0 equiv), 1-bromohexane (39.6 g, excess), tetrabutylammonium bromide (2.58 g, phase transfer catalyst), and 50% aqueous NaOH (75 mL) were sequentially added to a 250 mL round-bottom flask. 2. The reaction mixture was stirred at 80 °C overnight (about 12 hours). 3. After completion of the reaction, the reaction was cooled to room temperature and the organic layer was separated. 4. 4. The aqueous phase was extracted with ether (3 x 50 mL) and the organic phases were combined. 5. The organic phase was washed with saturated saline (100 mL) and dried over anhydrous magnesium sulfate. 6. The solvent was evaporated under pressure reduction, and the crude product was purified by short silica gel column chromatography to obtain 15.45 g of white solid product in 93.8% yield. Precautions. - 1-Bromohexane needs to be greatly overdosed to ensure complete reaction. - Tetrabutylammonium bromide as phase transfer catalyst can significantly improve the reaction efficiency. - The reaction temperature should be strictly controlled at 80 °C to avoid side reactions. - Petroleum ether/ethyl acetate (20:1) can be used as eluent for silica gel column chromatography.