Xylene (250 mL) was bubbled with nitrogen for 15 min, followed by addition of 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (4.6 g, 11.2 mmol) and Pd2(dba)3 (2.6 g, 2.8 mmol). The mixture was bubbled with nitrogen for 15 min, then [1,1′:3′,1″-terphenyl]-2′-amine (13.7 g, 56.0 mmol), 4-bromobiphenyl (13.0 g, 56.0 mmol), sodium tert-butoxide (10.8 g, 112.0 mmol) were added. The mixture was bubbled with nitrogen for 15 min and refluxed for 12 h. After cooling, the reaction mixture was filtered through a silica pad and washed with toluene. The solvent was removed in vacuo and the residue was purified by flash chromatography using 30-40% toluene/hexane to afford N-([1,1′-biphenyl]-4-yl)-[1,1′:3′,1″-terphenyl]-2′-amine (21.0 g, 93% yield) as a white solid.
