反应详情

To a toluene (100 mL) solution of 6-bromo-pyridine-3-carbaldehyde (5.0 g, 27 mmol) described in Manufacturing Example 154-1-1 were added ethylene glycol (3.0 mL, 54 mmol) and p-toluenesulfonic acid monohydrate (512 mg, 2.7 mmol), which was refluxed for 3 hours and 40 minutes under nitrogen atmosphere. Sodium hydrogencarbonate and water were added to the reaction mixture, which was extracted with ethyl acetate. The organic layer was separated, washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under a reduced pressure, and the residue was purified by NH silica gel column chromatography (heptane: ethyl acetate=1:1) to obtain the title compound (6.0 g, 97%).

1. temperaturewas refluxed for 3 hours and 40 minutes under nitrogen atmosphere
2. extractionwas extracted with ethyl acetate
3. customThe organic layer was separated
4. washwashed with saturated aqueous sodium chloride
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationThe filtrate was concentrated under a reduced pressure
8. customthe residue was purified by NH silica gel column chromatography (heptane: ethyl acetate=1:1)