反应详情

A solution of 3,6-dimethylpyridine-2-carbonitrile (4.44 g, 30.0 mmol) and conc. H2SO4 (2 drops) in acetic anhydride (30 mL) was stirred at 100° C. for 16 h, cooled to room temperature, poured into water (100 mL) and basified to pH 8 with saturated aqueous NaHCO3. The mixture was extracted with EtOAc (3×25 mL) and the combined organic phase dried (MgSO4) and concentrated in vacuo. The residue was treated with MeOH (100 mL), water (40 mL) and K2CO3 (8.8 g), stirred at room temperature for 1 h, concentrated in vacuo and partitioned between EtOAc and water. The organic phase was dried (MgSO4) and concentrated in vacuo to give the title compound (2.4 g, 51%) as a yellow oil; NMR δH (400 MHz, CDCl3) 2.57 (3H, s), 4.78 (2H, s), 7.42 (1H, d, J 8.5 Hz) and 7.67 (1H, d, J 8.5 Hz); M/Z 149 (M+H)+

1. extractionThe mixture was extracted with EtOAc (3×25 mL)
2. dry with materialthe combined organic phase dried (MgSO4)
3. concentrationconcentrated in vacuo
4. additionThe residue was treated with MeOH (100 mL), water (40 mL) and K2CO3 (8.8 g)
5. concentrationconcentrated in vacuo
6. custompartitioned between EtOAc and water
7. dry with materialThe organic phase was dried (MgSO4)
8. concentrationconcentrated in vacuo