反应详情

温度

150 °C

To a solution of 3 (2.3 g, 7.9 mmol) in dioxane (60 mL) were added tris(dibenzylideneacetone)dipalladium (0) (368 mg, 0.4 mmol), 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (696 mg, 1.2 mmol), and sodium t-butoxide (1.15 g, 12 mmol). The mixture thus obtained was heated at 150° C. under microwave irradiation for 3 h. The reaction mixture was passed through a short pack silica gel column and concentrated. The residue was purified by flash chromatography on silica gel eluting with 2% methanol in dichloromethane to give the title compound (4) as a white solid (1.71 g, 85%). 1H NMR (500 MHz, DMSO-d6) δ 9.05 (1H, s), 8.87 (1H, br. s), 8.37 (1H, d, J=4.9 Hz), 7.93 (1H, d, J=5.1 Hz), 6.97 (2H, br. s), 5.33 (1H, p, J=8.6 Hz), 2.27 (2H, m), 2.04 (4H, m), 1.76 (2H, m) ppm; LCMS-ESI (POS), M/Z, M+1: Found 254.1, Calculated 254.1.

1. customThe mixture thus obtained
2. concentrationconcentrated
3. customThe residue was purified by flash chromatography on silica gel eluting with 2% methanol in dichloromethane