反应详情

A mixture of pyridine-2-carboxaldehyde (32.1 g 0.30 mmol), malonic acid (62.4 g, 0.60 mmol) in pyridine (200 mL) and pyrrolidine (2 mL) was stirred under reflux for 16 hours. The reaction mixture was allowed to cool to room temperature and poured into ice water (200 mL). The aqueous layer was extracted with CH2Cl2 (2×100 mL). The combined organic layer was concentrated in vacuo and the crude material obtained was purified by flash column chromatography on silica using a gradient system of solvents: 1) ethyl acetate (100%); 2) methanol/ethyl acetate (10%). The title product was obtained (6.28 g, 14%) as a grayish-green solid.

1. temperatureunder reflux for 16 hours
2. extractionThe aqueous layer was extracted with CH2Cl2 (2×100 mL)
3. concentrationThe combined organic layer was concentrated in vacuo
4. customthe crude material obtained
5. customwas purified by flash column chromatography on silica using a gradient system of solvents