Reaction Steps
A 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer and reflux condenser was purged with nitrogen and charged with 120c (215 mg, 0.613 mmol), 103f (340 mg, 0.735 mmol), sodium carbonate (195 mg, 1.84 mmol), 1,4-dioxane (8 mL) and water (2 mL). This mixture was degassed with nitrogen for 30 min. Tetrakis(triphenylphosphine)palladium (71 mg, 0.061 mmol) was added. After heating at 100° C. for 3 h, the reaction mixture was cooled to room temperature and partitioned between water (40 mL) and methylene chloride (100 mL). The layers were separated, and the aqueous phase was extracted with methylene chloride (2×50 mL). The organic extracts were combined, dried over sodium sulfate, filtered and concentrated under reduced pressure. The resulting residue was dissolved in methanol (5 mL), and potassium carbonate (500 mg, 3.62 mmol) was added. After stirring at room temperature for 2 h, the reaction mixture was partitioned between water (20 mL) and methylene chloride (20 mL). The layers were separated, and the aqueous phase was extracted with methylene chloride (2×20 mL). The organic extracts were combined, dried over sodium sulfate, filtered and concentrated under reduced pressure. The resulting residue was purified by flash chromatography to afford 120 in 21% yield (72 mg) as an off-white solid: >250° C.; 1H NMR (500 MHz, DMSO-d6) δ 8.48 (s, 1H), 8.25 (d, 1H, J=2.0 Hz), 7.73-7.71 (m, 2H), 7.62 (d, 1H, J=8.5 Hz), 7.51-7.42 (m, 3H), 7.36 (d, 1H, J=7.5 Hz), 7.28 (d, 1H, J=2.0 Hz), 7.17 (d, 1H, J=9.0 Hz), 6.87 (dd, 1H, J=9.0, 3.0 Hz), 5.56 (d, 1H, J=6.5 Hz), 4.94 (s, 2H), 4.88 (t, 1H, J=5.0 Hz), 4.54 (m, 1H), 4.33 (d, 2H, J=5.0 Hz), 4.02 (t, 2H, J=7.0 Hz), 3.58 (s, 3H), 3.43 (t, 2H, J=7.0 Hz), 1.36 (s, 9H); MS (ESI+) m/z 566.3 (M+H).
