Water → 4-hydroxy-3-[3-[3-(2-cyanoethenyl)phenyl]-1-oxo-2-propenyl]-6-methyl-2H-pyran-2-one

Participants

Reaction Steps

A solution of 5.24 g of 3-acetyl-4-hydroxy-6-methyl-2H -pyran-2-one, 4.90 g of 3-(3-formylphenyl)-2-propenenitrile and 1.92 g of piperidine in 40 ml of chloroform was heated under refluxing for 35 minutes while water was removed with a Soxhlet's extractor filled with a molecular sieve. After cooling to room temperature, the reaction mixture washed successively with 10% hydrochloric acid, and an aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and concentrated. Precipitated crystals were filtered, and the crystals were subjected to silica gel column chromatography to obtain 4.05 g of 4-hydroxy-3-[3-[3-(2-cyanoethenyl)phenyl]-1-oxo-2-propenyl]-6-methyl-2H-pyran-2-one [Compound No. (1a)] as a pale yellow crystal.

Provenance & Evidence