The general procedure for the synthesis of 2-bromobenzo[9,10]phenanthrene from 9,10-benzo[9,10]phenanthrene was as follows (Example 1, Synthesis of Compounds A-8):
(1) Synthesis of compound d-2: Add compound d-1 (9.99 g, 43.8 mmol) and dichloromethane (300 mL) in a 500 mL three-neck flask. The reaction solution was stirred at room temperature under nitrogen protection and a mixed solution consisting of bromine (7.7 g, 48.2 mmol) and dichloromethane (7.0 mL) was added slowly dropwise. After the dropwise addition, the reaction solution was continued to be stirred at room temperature for 12 hours. Upon completion of the reaction, the reaction solution was quenched by pouring it into sodium thiosulfate solution. Subsequently, the organic layer was extracted with chloroform, combined and dried with anhydrous sodium sulfate. The organic layer was concentrated under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography (unfolding agent: toluene-heptane mixed solvent) to afford 11.6 g of compound d-2 as a white solid (yield: 86.3%).