反应详情

温度

80 °C

4-(Pyridin-2-ylmethoxy)pyridine 1-oxide (9.0 g, 45 mmol) was heated to 140° C. in acetic anhydride (100 mL) for 2 h. The solution was concentrated and then heated at 80° C. for 1 h in a mixture of MeOH (50 mL) and H2O (50 mL). The resultant black solution was concentrated and the residue was dissolved in hot i-PrOH (40 ml). Et2O (250 mL) was added and the mixture was placed in the freezer for 16 h. The solid was filtered off to provide the title compound (1.9 g, 21%) as a brown solid: 1H NMR (300 MHz, DMSO-d6) δ 11.13 (br s, 1H), 8.58 (d, J=4.7 Hz, 1H), 7.85 (overlapping ddd, J=7.9, 1.6 Hz, 1H), 7.49 (d, J=7.9 Hz, 1H), 7.38-7.34 (m, 1H), 7.26 (d, J=7.3 Hz, 1H), 5.96 (dd, J=7.3, 2.5 Hz, 1H), 5.76 (d, J=3.4 Hz, 1H), 5.12 (s, 2H).

1. concentrationThe solution was concentrated
2. concentrationThe resultant black solution was concentrated
3. dissolutionthe residue was dissolved in hot i-PrOH (40 ml)
4. additionEt2O (250 mL) was added
5. filtrationThe solid was filtered off