Xylene (250 mL) was bubbled with nitrogen for 15 min, followed by addition of 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (1.8 g, 4.4 mmol) and Pd2(dba)3 (1.0 g, 1.1 mmol). The mixture was bubbled with nitrogen for 15 min, then [1,1′:3′,1″-terphenyl]-4′-amine (9.8 g, 40.0 mmol), 4-iodobiphenyl (10.3 g, 36.7 mmol), sodium tert-butoxide (7.0 g, 73.4 mmol) were added. The mixture was bubbled with nitrogen for 15 min and refluxed for 13 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 40-60% toluene/hexane to afford N-([1,1′-biphenyl]-4-yl)-[1,1′:3′,1″-terphenyl]-4′-amine (14.7 g, 92% yield) as a white solid.
