反应详情

0.6 g of 3-chloro-6′-methyl-[2,3′]bipyridyl-5-carboxylic acid methyl ester (12) (2.3 mmol) prepared in Example 8 was dissolved in 10 mL of 1,4-dioxane, and 0.75 g of selenium dioxide (6.9 mmol) was added thereto. The mixture was refluxed under heating and stirring for 18 hours, and cooled to room temperature. The mixture was concentrated under reduced pressure, and then 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: chloroform/methanol=10/1) to obtain 0.51 g of yellow crystal, 3-chloro-6′-formyl-[2,3′]bipyridyl-5-carboxylic acid methyl ester (yield 81%)

1. temperatureThe mixture was refluxed
2. temperatureunder heating
3. concentrationThe 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: chloroform/methanol=10/1)