Toluene (200 mL) was bubbled with nitrogen for 15 min, followed by addition of 10% t-Bu3P in hexane (2.9 mL, 1.0 mmol) and Pd2(dba)3 (1.1 g, 1.2 mmol). The mixture was bubbled with nitrogen for 15 min, then N-([1,1′-biphenyl]-4-yl)-[1,1′:3′,1″-terphenyl]-4′-amine (10.6 g, 26.5 mmol), 4-iodoanisole (11.2 g, 48.0 mmol), sodium tert-butoxide (3.5 g, 36.0 mmol) were added. The mixture was bubbled with nitrogen for 15 min and stirred for 16 h at room temperature. The reaction mixture was filtered through a silica pad and washed with toluene (containing 0.5% triethylamine). The solvent was removed in vacuo and the residue was purified by flash chromatography using 30-40% toluene/hexane (containing 0.5% triethylamine) to afford N-([1,1′-biphenyl]-4-yl)-N-(4-methoxyphenyl)-[1,1′:3′,1″-terphenyl]-4′-amine (12.5 g, 94% yield) as a white solid.
