5802-17-5

92971-94-3

5802-17-5

Representative procedure: synthesis of 6-methoxybenzodihydropyran-4-one (7a). 2,3-Dihydro-4H-chromen-4-one (1.20 g, 6.18 mmol) was dissolved in a mixed acetonitrile-water solvent (10 mL, V/V=1:2) followed by the addition of cerium ammonium nitrate (CAN, 5 g, 9.27 mmol). The reaction mixture was heated to 70 °C under stirring, maintained for 30 min and then cooled to room temperature. After completion of the reaction, the mixture was diluted with water and extracted with ether (3 x 20 mL). The organic phases were combined, washed with saturated sodium bicarbonate solution (20 mL), and dried over anhydrous magnesium sulfate. After filtration, the filtrate was concentrated under reduced pressure to afford the title compound 6-methoxybenzodihydropyran-4-one as a yellow oil (0.64 g, 70% yield).