反应详情

A solution of 411 (45 mg, 0.08 mmol), 4-bromopyridine N-oxide (250 mg, 1.43 mmol), bistrimethyltin (26 μL, 40 mg, 0.12 mmol) and Pd(PPh3)4 (10 mg, 0.01 mmol) in dioxane (1 mL) was heated to reflux for 4 hrs. The reaction mixture was cooled, concentrated and the residue was purified by flash chromatography using the gradient 5-10% MeOH in DCM as an eluent, to afford 409 (11 mg, 27% yield). 1H NMR δ (400 MHz, CD3OD): 8.71 (d, 1H, J=5.4 Hz), 8.6 (m, 3H), 8.04 (dd, 1H, J=2.4 Hz, J=12.3 Hz), 7.85 (t, 1H, J=8.4 Hz), 7.78 (m, 2H), 7.65 (m, 1H), 7.62 (m, 1H), 7.53 (m, 3H), 7.32 (t, 1H, J=7.4 Hz), 6.81 (d, 1H, J=5.5 Hz), 3.75 (s, 2H). MS (m/z: (M+1) 515.0 (100%).

1. temperatureto reflux for 4 hrs
2. temperatureThe reaction mixture was cooled
3. concentrationconcentrated
4. customthe residue was purified by flash chromatography