4-Trifluoromethylphenylboronic acid

121-43-7

402-43-7

128796-39-4

[Example 4] In this embodiment, the synthesis of 9-[4-(carbazol-9-yl)phenyl]-10-(4-trifluoromethylphenyl)anthracene (CF3CzPA) represented by structural formula (42) is described. [Step 1] Synthesis of 9-bromo-10-(4-trifluoromethylphenyl)anthracene (i) Synthesis of 4-(trifluoromethyl)phenylboronic acid The synthesis scheme of 4-(trifluoromethylphenylboronic acid) is shown in (E-1). (1) 33 g (0.15 mol) of p-bromobenzotrifluoride was added to a 500 mL three-necked flask under nitrogen protection. Subsequently, 200 mL of tetrahydrofuran (THF) was added and the mixture was stirred. The mixed solution was cooled to -78 °C and 100 mL (0.16 mol) of n-butyllithium (1.6 mol/L) solution was slowly added dropwise through a dropping funnel. After the dropwise addition was completed, stirring was continued for 1 hour by keeping it at -78°C. Then, 22.3 mL (0.20 mol) of trimethyl borate was added and the reaction mixture was gradually warmed to room temperature and stirred for about 12 hours. After the reaction was completed, 100 mL of dilute hydrochloric acid (1 mol/L) was added to the reaction solution and stirring was continued for 1 hour. The aqueous layer was extracted three times with ethyl acetate, the organic layers were combined, washed once with saturated brine and dried with magnesium sulfate. The magnesium sulfate was removed by filtration and the filtrate was concentrated to obtain the solid product. The solid was washed with chloroform to give a final 15 g of white solid target product 4-trifluoromethylphenylboronic acid in 54% yield.