Reaction Steps
A mixture of 3-(3,5-dimethyl-1H-pyrazol-1-yl)phenol 2 (5.00 g, 26.56 mmol, 1.0 eq), 4′-iodo-2-nitrobiphenyl (10.38 g, 31.92 mmol, 1.2 eq), CuI (0.25 g, 1.33 mmol, 0.05 eq), picolinic acid (0.33 g, 2.66 mmol, 0.1 eq) and K3PO4 (11.28 g, 53.12 mmol, 2.0 eq) in DMSO (60 mL) was stirred at a temperature of 80-90° C. for three days under a nitrogen atmosphere, then cooled to ambient temperature. The solid was filtered off and washed with plenty of ethyl acetate (250 mL). The filtrate was washed with water three times and then dried over sodium sulfate and filtered. The filtrate was concentrated under reduced pressure, and the residue was purified through column chromatography on silica gel using hexane/ethyl acetate (10:1-5:1-3:1) as an eluent to obtain the desired product as a sticky liquid (9.38 g in 92% yield). 1HNMR (DMSO-d6, 400 MHz): δ 2.15 (s, 3H), 2.30 (s, 3H), 6.06 (s, 1H), 7.07 (dd, J=8.0, 2.4 Hz, 1H), 7.13-7.16 (m, 3H), 7.30-7.32 (m, 1H), 7.36-7.40 (m, 2H), 7.52 (t, J=8.0, 1H), 7.57 (dd, J=7.6, 1.2 Hz, 1H), 7.59-7.64 (m, 1H), 7.75 (td, J=7.6, 1.2 Hz, 1H), 7.97 (dd, J=8.0, 1.2 Hz, 1H). 13C NMR (DMSO-d6, 100 MHz): δ 12.30, 13.27, 107.63, 114.22, 117.18, 118.91, 118.97, 124.10, 128.81, 129.73, 130.61, 131.84, 132.28, 132.92, 134.33, 139.35, 141.11, 148.20, 148.92, 156.52, 156.67.
