Reaction Steps
A mixture of 2-(3-(3,5-dimethyl-1H-pyrazol-1-yl)phenoxy)-9H-carbazole 4 (530 mg, 1.5 mmol, 1.0 eq), 2-bromo-4-tert-butylpyridine (642 mg, 3.0 mmol, 2.0 eq), Pd2(dba)3 (55 mg, 0.06 mmol, 0.04 eq), JohnPhos (36 mg, 0.12 mmol, 0.08 eq) and tBuONa (231 mg, 2.4 mmol, 1.6 eq) in toluene (6 m) and dioxane (6 mL) was stirred at a temperature of 95-105° C. for 2 days under a nitrogen atmosphere. Then the mixture was cooled to ambient temperature. The solvent was removed under reduced pressure and the residue was purified through column chromatography on silica gel using hexane/ethyl acetate (10:1-5:1) as an eluent to obtain the desired product as a brown solid (685 mg in 94% yield). 1H NMR (DMSO-d6, 400 MHz): δ1.26 (s, 9H), 2.11 (s, 3H), 2.23 (s, 3H), 6.00 (s, 1H), 7.06-7.08 (m, 1H), 7.10 (dd, J=8.0, 2.4 Hz, 1H), 7.14 (t, J=2.4 Hz, 1H), 7.24-7.26 (m, 1H), 7.31 (t, J=7.2 Hz, 1H), 7.38 (d, J=2.0 Hz, 1H), 7.41-7.48 (m, 3H), 7.61 (d, J=1.6, 1H), 7.74 (d, J=8.4 Hz, 1H), 8.20 (d, J=8.0 Hz, 1H), 8.26 (d, J=8.8 Hz, 1H), 8.55 (d, J=4.8 Hz, 1H). 13C NMR (DMSO-d6, 100 MHz): δ12.21, 13.22, 30.01, 34.81, 101.37, 107.50, 111.11, 113.01, 113.81, 115.78, 116.80, 118.49, 119.27, 119.72, 120.13, 121.11, 121.83, 123.20, 125.90, 130.45, 139.19, 139.43, 139.94, 141.01, 148.07, 149.37, 150.60, 155.32, 157.50, 163.03.
