302554-81-0

61676-62-8

302554-80-9

302554-81-0

Under argon protection, 9,9-dioctyl-2-bromofluorene (14.1 g, 0.03 mol) was dissolved in 180 mL of purified tetrahydrofuran (THF). A hexane solution of 1.6 mol/L n-butyllithium was slowly added dropwise at -78 °C. After maintaining the reaction at -78 °C for 2 h, 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (25 mL) was added and the reaction was continued for 1 h at -78 °C. Subsequently, the reaction system was slowly warmed to room temperature and stirred for 24 hours. Upon completion of the reaction, the mixture was poured into water and extracted with ethyl acetate. The organic layers were combined, washed with saturated brine and subsequently dried with anhydrous magnesium sulfate. The organic phase was concentrated under reduced pressure to give a light yellow viscous substance. The product was purified by silica gel column chromatography (eluent: petroleum ether/ethyl acetate = 20/1, v/v) and placed in a refrigerator for a prolonged period of time to give a white solid in 70% yield.