反应详情

4.0 g of 3-chloro-6′-methyl-5-vinyl-2,3′-bipyridine (14) (17.3 mmol) prepared in Example 10 was dissolved in 50 mL of 1,4-dioxane, and 5.8 g of selenium dioxide (52 mmol) was added thereto. The mixture was refluxed under heating and stirring for 18 hours, and cooled to room temperature. Then, the mixture was concentrated under reduced pressure, and dissolved in ethyl acetate to be washed with water. The organic layer was dried over magnesium sulfate, and concentrated under reduced pressure. The residue was separated by column chromatography (eluting solvent:ethyl acetate/hexane=1/4) to obtain 3.2 g of 3-chloro-5-vinyl-2,3′-bipyridine-6′-carbaldehyde (yield 75%).

1. temperatureThe mixture was refluxed
2. temperatureunder heating
3. concentrationThen, the mixture was concentrated under reduced pressure
4. dissolutiondissolved in ethyl acetate
5. washto be washed with water
6. dry with materialThe organic layer was dried over magnesium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe residue was separated by column chromatography (eluting solvent:ethyl acetate/hexane=1/4)