Water → 4-hydroxy-3-[3-[3-[(2-methoxyethoxy)carbonylamino]phenyl]-1-oxo-2-propenyl]-2H-1-benzopyran-2-one

Participants

Reaction Steps

In 10 ml of chloroform were dissolved 2.04 g of 3-acetyl-4-hydroxy-2H-1-benzopyran-2-one, 2.23 g of 3-[(2-methoxyethoxy)carbonylamino]benzaldehyde and 60 mg of piperidine, and the solution was heated under refluxing for 1 hour and 30 minutes while water was removed with a Soxhlet's extractor filled with a molecular sieve. After cooled to room temperature, the reaction mixture was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography, and fractions corresponding to Rf=0.3 were collected by thin layer chromatography (silica gel, hexane/acetone (1:1)), and concentrated to obtain 3.42 g of 4-hydroxy-3-[3-[3-[(2-methoxyethoxy)carbonylamino]phenyl]-1-oxo-2-propenyl]-2H-1-benzopyran-2-one [Compound No. (24d)].

Provenance & Evidence