反应详情

A solution of 5-bromo-6-chloro-1H-indole (5.92 g, 25.7 mmol), sodium carbonate (5.45 g, 51.4 mmol) and (4-ethoxyphenyl)boronic acid (5.12 g, 30.8 mmol) in EtOH/water/toluene (30 mL, each) was degassed with N2 for 5 minutes, treated with tetrakis(triphenylphosphine)palladium (1.8 g, 16.57 mmol) and degassed for an additional 5 minutes. The reaction mixture was heated to reflux under N2 for 16 hours. The reaction mixture was cooled to room temperature, poured into dilute NH4Cl solution (200 mL), and extracted with CH2Cl2 (3×100 mL). The combined organic layers were washed with brine (100 mL), dried over Na2SO4 and concentrated in vacuo. The crude material was purified by flash chromatography (9-25% EtOAc/petroleum ether) to afford the title compound (6.03 g, 86%) as a white solid. 1H NMR (400 MHz, CDCl3) δ 8.07 (br, 1 H), 7.50 (s, 1 H), 7.43 (s, 1 H), 7.33 (d, 2 H), 7.15 (m, 1 H), 6.89 (d, 2 H), 6.46 (s, 1 H), 4.02 (q, J=7.00 Hz, 2 H), 1.36 (t, J=7.00 Hz, 3 H).

1. customdegassed for an additional 5 minutes
2. temperatureThe reaction mixture was heated
3. temperatureto reflux under N2 for 16 hours
4. additionpoured into dilute NH4Cl solution (200 mL)
5. extractionextracted with CH2Cl2 (3×100 mL)
6. washThe combined organic layers were washed with brine (100 mL)
7. dry with materialdried over Na2SO4
8. concentrationconcentrated in vacuo
9. customThe crude material was purified by flash chromatography (9-25% EtOAc/petroleum ether)