Synthesis
General procedure for the synthesis of 4-(9-carbazolyl)phenylboronic acid from 9-(4-bromophenyl)carbazole: 9-(4-bromophenyl)carbazole (35 g, 108.6 mmol) was dissolved in tetrahydrofuran (THF, 600 mL), and n-butyllithium (n-BuLi, 52 mL, 130.35 mmol, -78 °C) was slowly added to the reaction system. 2.5 M hexane solution). The reaction mixture was stirred at this temperature for 1 hour. Subsequently, the reaction system was slowly warmed to room temperature and triisopropoxyborane (B(Oi-Pr)3, 37 mL, 162.9 mmol) was added dropwise to the reaction mixture during this process. The reaction mixture was continued to be stirred at room temperature for 12 hours. Upon completion of the reaction, extraction was carried out with ethyl acetate (EA), the organic layers were combined and dried over anhydrous magnesium sulfate (MgSO4) to remove water. Subsequently, the solvent was removed by distillation under reduced pressure and the crude product obtained was recrystallized by a solvent mixture of ethyl acetate and hexane to give 4-(9-carbazolyl)phenylboronic acid (25 g, 81% yield).
References
[1] Organic and Biomolecular Chemistry, 2012, vol. 10, # 33, p. 6693 - 6704
[2] Australian Journal of Chemistry, 2007, vol. 60, # 8, p. 603 - 607
[3] Physical Chemistry Chemical Physics, 2011, vol. 13, # 39, p. 17825 - 17830
[4] Organic and Biomolecular Chemistry, 2012, vol. 10, # 47, p. 9481 - 9490
[5] Patent: WO2013/12297, 2013, A1. Location in patent: Paragraph 111; 114; 115
