503299-24-9

1084334-86-0

2-2. Preparation of Compound 10: N-(4-bromophenyl)-N-phenyl-[1,1'-biphenyl]-4-amine (15.0 g, 37.5 mmol) was dissolved in tetrahydrofuran (190.0 mL) and n-butyllithium (2.5 M hexane solution, 22.0 mL) was slowly added to the solution at -78°C. After the reaction mixture was stirred at -78 °C for 1 h, trimethoxyborane (6.3 mL, 56.21 mmol) was added. Subsequently, the reaction mixture was warmed to room temperature and stirring was continued for 4 hours. Upon completion of the reaction, the mixture was extracted with ethyl acetate (200.0 mL) and the organic layer was washed with distilled water (100.0 mL). The organic solvent was removed by concentration under reduced pressure and the solid obtained was washed with hexane, filtered and dried to give 4-[N-(biphenyl-4-yl)-N-phenylamino]phenylboronic acid (10.0 g, 73% yield).