反应详情

A solution of 5.2 g of 2-bromo-6-[2-(3-methoxycarbonylphenyl)ethinyl]-pyridine in 30 ml of 60% sulfuric acid is heated to 140° C. with stirring for 1.5 hours. After cooling to room temperature, the reaction mixture is poured on ice water, the precipitate is suctioned off, and washed neutral with water. After drying at 50° C. in a vacuum, the crude product is dissolved in 35 ml of methanol, mixed with 3 drops of concentrated sulfuric acid and refluxed for 8 hours. Then, the reaction mixture is concentrated by-evaporation, distributed between water and ethyl acetate, the organic phase is washed with 10% sodium bicarbonate and water, dried on sodium sulfate and concentrated by evaporation. 3.5 g of 2-bromo-6-[(3-methoxycarbonylbenzoyl)-methyl]-pyridine of melting point 84°-86° C. is obtained.

1. additionthe reaction mixture is poured on ice water
2. washwashed neutral with water
3. customAfter drying at 50° C. in a vacuum
4. dissolutionthe crude product is dissolved in 35 ml of methanol
5. additionmixed with 3 drops of concentrated sulfuric acid
6. temperaturerefluxed for 8 hours
7. concentrationThen, the reaction mixture is concentrated
8. customby-evaporation
9. washthe organic phase is washed with 10% sodium bicarbonate and water
10. customdried on sodium sulfate
11. concentrationconcentrated by evaporation