反应详情

0.5 g of p-[(E)-2-(3,4-dihydro-4,4-dimethyl-1-benzopyran-6-yl)propenyl]benzyl alcohol was dissolved in 20 ml of methylene chloride and the solution is treated with 10 g of manganese dioxide. After stirring at room temperature for 6 hours, the solid material is filtered off, rinsed well with methylene chloride and the filtrate was evaporated. After recrystallization of the residue from hexane/ether, there are obtained 350 mg of p-[(E)-2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl)propenyl]benzaldehyde of melting point 102°-104° C.

1. filtrationthe solid material is filtered off
2. washrinsed well with methylene chloride
3. customthe filtrate was evaporated
4. customAfter recrystallization of the residue from hexane/ether, there