反应详情

30 mg of 2,2-dimethyl-4-(4methoxyphenyl)-5-{4-(methylsulfonyl)phenyl}-3(2H)-furanone (Example 3) in 30 ml dichloromethane was stirred with 0.1 ml boron tribromide (1.0 M solution in CH2Cl2) at room temperature for 4 hours. And then 10 ml aqueous sodium thiosulfate was added to the reaction mixture. The mixed solution was concentrated in vacuo and was extracted with 50 ml water and dichloromethane (50 ml×3). The organic layer was concentrated under reduced pressure and was purified by column chromatography (ethylacetate) to afford 25 mg of 2,2-dimethyl-4-(4-hydroxyphenyl)-5-{4-(methylsulfonyl)phenyl}-3(2H)-furanone. mp: 150-152° C. NMR: δ1.56 (s, 6H), 2.77 (s, 1H), 3.07 (s, 3H), 6.81 (d, J=8.7 Hz, 2H), 7.14 (d, J=8.7 Hz, 2H), 7.90 (m, 4H). IR (cm−1): 3492, 2929, 1696, 1597, 1393, 1151, 914, 744.

1. concentrationThe mixed solution was concentrated in vacuo
2. extractionwas extracted with 50 ml water and dichloromethane (50 ml×3)
3. concentrationThe organic layer was concentrated under reduced pressure
4. customwas purified by column chromatography (ethylacetate)