HCID 54292911, compound → HCID 54497255, compound

Participants

Reaction Steps

To a solution of 6-methyl-2-oxo-4-phenyl-2H-1-benzopyran-3-carboxylic acid ethyl ester (15.0 g) in acetic acid (150 ml) was added 10% palladium-carbon (3.0 g), followed by stirring at 80° C. in a hydrogen atmosphere (4 to 5 atm) for 4.5 hours. After the catalyst was filtered off, the filtrate was distilled to remove the solvent, followed by treatment of the residue with isopropyl ether, to yield 3,4-dihydro-6-methyl-2-oxo-4-phenyl-2H-1-benzopyran-3-carboxylic acid ethyl ester as colorless crystals (12.5 g).

Provenance & Evidence